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HomeMy WebLinkAboutHabitat Management Plan 978900016t, WESTECH COMPANY Environmental Consulting - Site Permitting MITIGATION AND HABITAT MANAGEMENT PLAN 460 OLYMPUS BOULEVARD dEftkHSIIN COUNTY gGfll ASSESSOR'S PARCEL # 978-900-016 JEFFERSON COUNTY, WASHINGTON v �� � x�.+? "°' w# , April 2016 G. Bradford Shea, Ph.D. Submitted to: JEFFERSON COUNTY DEPARTMENT OF COMMUNITY DEVELOPMENT 621 Sheridan Street Port Townsend, Washington 98368 Submitted by: WESTECH COMPANY P.O. Box 2876 Port Angeles, Washington 98362 P.O. Box 2876 - Port Angeles, Washington 98362 - Telephone: (360) 565-1333 email: bmd(@westechcompany.com MITIGATION AND HABITAT MANAGEMENT PLAN 460 OLYMPUS BOULEVARD ASSESSOR'S PARCEL # 978.900-016 JEFFERSON COUNTY, WASHINGTON April 2016 G. Bradford Shea, Ph.D. Copyright 2016 by G. Bradford Shea, Westech Company -All Rights Reserved Submitted to: JEFFERSON COUNTY DEPARTMENT OF COMMUNITY DEVELOPMENT 621 Sheridan Street Port Townsend, Washington 98368 Submitted by: WESTECH COMPANY P.O. Box 2876 Port Angeles, Washington 98362 CONTENTS CHAPTERISECTION PAGE NO. 1.0 INTRODUCTION 1 1.1 Background 1 1.2 Proposed Project 1 1.3 Regulatory Framework 1 2.0 APPROACH AND METHODS 7 2.1 Approach 7 2.2 Methods 7 3.0 MITIGATION PLAN 10 3.1 Regulatory Setting 10 3.2 Existing Conditions 12 3.3 Project Impacts 13 3.4 Plan Components 15 3.5 Detailed Mitigation Measures 15 3.6 Implementation and Timing 16 3.7 Mitigation Monitoring 16 3.8 Contingency Plan 18 4.0 PLANTING PLAN 19 5.0 CONCLUSIONS AND RECOMMENDATIONS 23 5.1 Conclusions 23 5.2 Recommendations 23 6.0 CERTIFICATION 25 7.0 REFERENCES 26 TABLES Table 1. List of Native Plants for Buffer Mitigation and Enhancement 21 FIGURES Figure 1. Location Map 2 Figure 2. Vicinity Map 3 Figure 3. Parcel Map 4 Figure 4. 2015 Aerial Photograph 5 Figure 5. Site Map 8 Figure 6. Planting Areas A, B and C 20 APPENDICES Appendix A — Site Photographs A_1 W W 1473-OlympusBlvd HM P.TOC/041216fmas 1.0 INTRODUCTION 1.1 BACKGROUND The Property (Site) is located at 460 Olympus Boulevard in Jefferson County Washington. The Property is owned by Thomas Balzarini (3535 South 126' Street, Seattle, Washington 98168). It is recorded as Assessor's Parcel # 978-900-016. The Site fies within Jefferson County, Washington in Section 4 of Township 28 North, Range 1 East, W.M. (Figures 1, 2, 3, and 4). The Site is located at the northern end of Port Ludlow on the western shore of Hood Canal and Port Ludlow Bay in unincorporated Jefferson County, Washington. The property is about 178 feet long by 61 feet wide or 0.25 acres. The Parcel has a six to eight (6-8) foot high bank above Port Ludlow Bay and Admiralty Inlet, with a cobble -sand beach at the foot of the bank. The bank slopes back at a relatively steep angle from the Ordinary High Water Mark (OHWM) and there is set of stairs to the beach. An existing pathway provides access to the property from Olympus Blvd. Parking is along Olympus Blvd. and there is another residence between Olympus Blvd., and the property (450 Olympus Blvd.) 1.2 PROPOSED PROJECT The property currently contains a one story house (cabin) with an irregular T- shaped footprint (roughly 616 square feet) with a 124 square foot covered porch (Rankin 2015). There is an existing septic system which will be replaced (Martin 2015). Planned construction activities include demolition of the existing house (one - bedroom cabin) and construction of a new two-bedroom home on the approximate location of the existing structure. The new home will be roughly 40x50 (1668 square feet), with a 652 square foot wooden deck (Rankin 2015). A new drainfield area will be constructed west of the new house (away from the water). Stormwater drainage pipes will be as per the engineered Drainage Plan for the Site (Zenovic & Associates 2016). This plan is shown on Figure 5. It includes use of a silt fence during construction and tight -lining and energy dissipation for stormwater runoff. This is further discussed in Sections 3.0 and 5.0. 1.3 REGULATORY FRAMEWORK The marine shoreline along this Property is considered a Shoreline of Statewide Significance and has been designated as critical habitat for Hood Canal Summer Chum and Puget Sound Chinook (50 C.F.R. 226). The shoreline is classified as a "Fish and Wildlife Habitat Conservation Area" (FWHCA) by Jefferson County, normally requiring a 150 foot buffer from the OHWM. W W1473-OlympusBlvdHMP.RPT/041116/mas I n �, yf N. �� S N , L �_ W F WW {�` (� C j o �� 3 v�� a. Lz -y f � _ ry -� � �� / �� a P a i i l—__ � .. � L` U� f � • d�' _ �i . ,;' ^:. v i ,.� /m' fE 4 fYj � "i \m 0 L �_ u 00 c Ir It is the intention of the owner to demolish the current residence on-site and replace it with a new, larger residence on roughly the existing footprint location within the 150 foot shoreline buffer. The house will have an expanded footprint to the northeast and southeast, with a new deck area east of the residence (footprint expansion of about 1,250 square feet for the residence and an expansion of 500 square feet for the deck). The new residence will lie at a distance of about 75 feet from the OHWM and the deck will extend to about 55 feet from OHWM. The owner has a septic permit SEP15-00112 for the septic system upgrade, with a drainfield area west of the house. The Septic system will be upgraded as per conditions of the permit and the Jefferson County Health Department. Because of the proposed home expansion and septic and storm -drainage construction, the Project will disturb surface soils and some existing vegetation. Stormwater drains will be placed as specked in the drainage plan (Zenovic & Associates 2016). The Property owner's engineer has contracted with Westech Company (Westech) to satisfy the County's requirements in regards to Critical Areas and Shoreline Buffer Requirements through preparation of this Habitat Management Plan. This Report constitutes a Habitat Management Plan (HMP) which will describe existing conditions on the Site, define the impacts of development, and outline a management proposal to maintain and enhance the existing functions and values of the buffer and its associated watershed and to ensure "No Net Ecological Loss of Shoreline Functions" (RCW36.70A.480). This document is intended to satisfy the requirements of pertinent Jefferson County and State regulations and ordinances. W W1473-0IympusBNdHMP.RPT/0411161mas 2.0 METHODS 2.1 APPROACH The approach for this investigation into the impacts of development of this Site included a detailed review of County Assessor's parcel maps, Critical Area Maps, aerial photographs of the Site, mapped locations of Species of Concern by the Washington State Department of Fish and Wildlife, mapped locations of ESA (Endangered Species Act) listed species' critical habitat by NOAA-NMFS (National Marine Fisheries Service) and topographic maps of the area. A Site Plan prepared by Zenovic & Associates (2016) was also reviewed and utilized to help define proposed planting areas (see Section 3.3 and Figure 5). During April 2016, the proposed home design with the current planned septic locations and stormwater drainage features were reviewed (Jefferson County Public Health 2015; Zenovic & Associates 2016)). An architectural plan for the Site (Rankin 2015) was also reviewed, as was a geotechnical report by Zenovic & Associates (2010). Westech's field investigations for the Habitat Management Plan (HMP) were carried out in March 2016 by Dr. G. Bradford Shea, Principal Ecologist. During Site visits, the Property was inspected and Site characteristics were noted. Relevant measurements were taken for mapping purposes, photographic documentation of the Site was acquired, and potential mitigation was identified. Updated plans and studies cited above were reviewed by Dr. Shea during March and April 2016. 2.2 METHODS Westech's field reconnaissance involved examining the existing conditions found at the Site. This included reviewing the area proposed for development in relation to the natural features found on-site. Botanical studies were conducted involving identification of plant species that could be found growing at the Site. Site measurements were taken (including dimensions of proposed planting areas) using fiberglass and steel tape measures. A qualitative assessment of the landscape was conducted to determine the presence of invasive species, the composition and characteristics of plants in the critical area, evidence of historical land uses, the slope of lands adjacent to critical areas, soil textures and stability and an assessment of the role of existing vegetation in supporting soil stability. Westech also assessed the extent of existing human disturbance in the critical areas. This information was used to assess the potential impacts of the proposed project. WW 1473-OlympusBlvdHMP.RPT/041116/mas va A 02�P I niV SIIYI:%KS\rJ vc R)110NI w � � � ¢, t a' 14-ON-1 .. IS �\ I18.LN- g� o � n - mn.ay."n"�.m.w. ou. ry un w m m L6 AM ILL This HMP has been formulated to assure "no net ecological loss" and to "maintain or enhance the existing functions and values of the associated watershed" (JCC 18.22.480; RCW36.70A.480). Chapters 3.0 and 4.0 describe the goals and objectives of this HMP as well as the performance standards that will be utilized to assess the effectiveness of this plan. This Plan is intended to restore and enhance the integrity of the Site by improving the quality of habitat and erosion control through planting of additional native vegetation at the Site. These recommendations have been formulated to be implemented in accordance with recommendations for erosion control by Zenovic & Associates (2010, 2016). VWV1473-0 ympusBWHMP. RPT/041116/mas 3.0 MITIGATION PLAN 3.1 REGULATORY SETTING There are several jurisdictional issues related to the development of this parcel of land. The Site is a medium -low bank site (6-8 feet at top of bank), with gradual uphill topography to an elevation of about 45 feet above mean sea level (msl). The steep bank hillslope above the beach slopes back sufficiently (about 35-45 degrees) to be well covered with vegetation, mostly shrubs and herbaceous species. The area in front of the proposed home is moderately sloped (15-25 %) for a distance of 30 feet to the forward edge of the proposed deck. The proposed residence addition is located approximately 55 feet from the top of bank and about 75 feet from MHHW. The Site is zoned Rural Residential (RR -5). The purpose of rural residential zoning is to allow for "continued residential development" in areas of the County of "relatively high density pre-existing patterns of development," including "along the County's coastal areas" (JCC 18.15.015). "In addition, this district seeks to support and foster Jefferson County's existing rural residential landscape and character by restricting new land divisions to a base density of 1 unit per 5 acres" The Site is located along a section of shoreline that is considered a "Shoreline of Statewide Significance" and is regulated under Jefferson County's Shoreline Master Program. This shoreline has been designated under the Shoreline Master Program as a suburban "Shoreline Residential (SR)" shoreline (Jefferson County 2016a,b). Shoreline Residential (SR) is a shoreline designation which "is assigned to shoreline areas landward of the Ordinary High Water Mark (OHWM) if they do not meet the criteria for natural, conservancy, or high intensity environments" and "if the shoreline is predominantly high density (RR1:5) single family or multifamily residential development or is planned and platted for high density (RR1:5) residential development." The permitted activities in these areas include single family homes (and normal appurtenances) (JCC 18.25.220). Under the Shoreline Master Program the standard set -back for residential structures is "30 feet" or one foot per foot of bank height, whichever is greater." This set -back is to be measured from the bank's edge when the bank height is greater than 10 feet and shall not exceed 100 feet. The elevation of the bank at this property is approximately 6-8 feet of moderately steep bluff. The property grades upward to a maximum height of about 45 feet at the southern property line. WW1473-01ympusB1vdHMP. RPT/041116/mas 10 The underlying Site soils are considered stable in terms of shoreline stability. The site is mapped by the County as a landslide hazard area, however, there are no seismic or erosion hazard areas on the property (Jefferson County 2016). The Geotechnical Report (Zenovic & Associates 2010) indicates that the mapping of the Site as a Landslide Area is not accurate. Erosion is rated as low provided the Site remains sufficiently vegetated. This shoreline has been designated "critical habitat' for threatened salmonid species, specifically the Puget Sound Chinook and Hood Canal Summer Chum. This listing comes from the National Marine Fisheries Service (NMFS) pursuant to the Endangered Species Act (ESA). The Growth Management Act (RCW36.70A.480) mandates that the County protect such critical areas. Jefferson County carries out this mandate by classifying this shoreline as a "Fish and Wildlife Habitat Conservation Area" (FWHCA). These areas are considered to be of "critical importance to the maintenance of endangered, threatened or sensitive species of fish, wildlife, and/or plants' (18.22.200). Jefferson County requires a buffer of 150 feet from the Ordinary High Water Mark (OHWM) for areas in which "federally listed species have a primary association." In addition, a ten foot building setback from the buffer is required. Local and site specific factors may be taken into account and the buffer width is to be "based on the best available information concerning the species/habitat in questions' (JCC 18.22.270(2)). Any project located within this buffer must follow Jefferson County drainage and erosion control, grading and vegetation retention standards (JCC 18.22.270). Landowners may obtain a reduction in the size of the buffer required for FWHCAs. The administrator has the "authority to reduce buffer widths on a case- by-case basis" provided that standards are met for avoiding and minimizing impacts and that the buffer reduction does not "adversely affect the habitat functions and values of the adjacent FWHCA or other critical area" (JCC 18.22.270). However, the administrator may not reduce the buffer to less than 75 percent of the standard buffer (JCC 18.22.270). Any projects that "alter, decrease or average the standard buffer" require an accompanying Habitat Management Plan (HMP) (JCC 18.22.265). Because this project involves elements to be built in the buffer area, on an existing footprint, an HMP is required to mitigate and offset any adverse ecological effects. This document is also the best way to meet the intent of RCW36.70A.480 which provides for Jefferson County to make a determination of "No net loss of ecological functions" with or without mitigation, for renovation of existing shoreline structures. This document includes a "No Net Loss" ecological evaluation, proposed Mitigation Measures to offset impacts and a Habitat Management Plan to assure long-term health and ecological productivity of the buffer zone. WW1 473-01yrnpus3 lvd H M P. RPT/041116/mas 11 These documents (HMPs) must include maps showing the proposed development Site and its relationship to surrounding topographic features; the nature and density of the proposed development; and the boundaries of forested areas. The report shall also describe the density and nature of the proposed development in enough detail to allow analysis of impacts on identified fish and wildlife habitat. The report must describe how any adverse impacts resulting from the project will be mitigated. Possible Mitigation Measures for an HMP may include, but are not limited to, establishing buffer zones, preserving plant and tree species, limiting access to habitat areas, seasonally restricting construction activities and establishing a timetable for the periodic review of the Plan (18.22.440). 3.2 EXISTING CONDITIONS The Site is located roughly 1.5 miles north of Port Ludlow in unincorporated Jefferson County. The land area of the parcel is approximately 178 feet long (average) by 61 feet wide. The entire parcel is approximately 0.25 acres in size. Parking is along Olympus Boulevard and there is no direct vehicular access to the property. Figure 5 shows topographic features on the Site and the proposed development. The parcel abuts a sand -cobble beach to the east. The bank rises 6-8 feet on a relatively steep bluff, with the parcel rising to 45 feet msl on its southwestern corner. The property presently supports a small residence and septic system, bordered by lawn and a mixture of native and non-nafive shrubs. The shoreline adjacent to the property has been designated as critical habitat for two species listed as threatened under the Endangered Species Act: Puget Sound Chinook and Hood Canal Summer Chum (50 C.F.R. 226). The house area is characterized by low grasses (lawn area), however a few native trees, mainly Douglas fir (Pseudotsuga menziesit) and western red cedar (Thuja plicata) are present along the northern property border. Other, non-native species include ivy and Himalayan blackberry. Small red alder (Alms rubra) trees are present along part of the shoreline area and other large shrubs are present adjacent to the residence including rhododendron (Rhododendron spp.) and sword fern (Polystichum munitum). Ocean spray (Holodiscus discolor), salal (Gauttheria shallop) and salmonberry (Rubus spectabilis) are also present on the site. W W 1473-0Iympusl3lvdHMRRPT/0411161mas 12 The Natural Resource Conservation Service (NRCS) has mapped one dominant soil on the upland portion of the Site (NRCS 2016) plus beaches. Because NRCS maps can be inaccurate at this scale it is not possible to determine the actual boundary between these soils or the specific soils among these that are found on- site. These soils include: Coastal Beaches. This soil is usually very well drained (sand, gravel and cobble) and has a depth to water table of about 0 - 72 inches. It has a high frequency of flooding. It consists of sands and gravels to a depth of 72 inches. These soils are subject to influence of tides and storm waves. Alderwood gravelly sandy loam — 0-15 percent slopes (AIC) and 15- 30 percent slopes AID. These are moderately well -drained soils formed on terraces and hillslopes above glacial till at depths of 23-60 inches. These soils are moderately well drained above the till and drainage is very slow within it. Runoff is medium to rapid. Hazard of water erosion is slight to moderate. The Site has coastal beach soils at the eastern edge, with most of the Site underlain by Alderwood soils. These soils tend to be dominant along this area of Admiralty Inlet. 3.3 PROJECT IMPACTS The landowner's plan for this Property entails the expansion of the existing house footprint following demolition and removal of the existing structure (Figure 5). The project also involves new stormwater drainage replacement of the existing septic system within the area west of the house as per the current County septic permit (Jefferson County 2016c). The primary impacts associated with this project are those generally associated with construction. Figure 5 is a map of the existing and proposed structural footprint on the Site. The existing house including front deck. The proposed structure will be built on the footprint of 1868 square feet as shown, and will not extend significantly further waterward than the front of the existing house. A 652 square foot deck will be located on the east side of the main residence. This will replace the existing 124 square That covered porch. WVV1473-OlympusBlvdHMP.RPT/041116/mas 13 The current septic tank will be replaced by three tanks located beneath the new deck, as shown in the septic plan (Martin 2015) and as approved by the Jefferson County Health Department (Jefferson 2016c). The reserve drainfield required by the County will be located west of the residence and north of the new main drainfield area (Martin 2015). The potential impacts of this project will result primarily from the processes of grading and clearing the areas for construction of the new home and septic system. These potential impacts include the following: The area surrounding the new home and the area near the storm - drainage pipes will be cleared. Also, the drainfield area will need to be cleared. This may create the conditions for potential short-term erosion and soil instability caused by the construction process and the removal of some vegetation in the buffer (mostly lawn area and existing shrubs). Additional earth moving and grading during the construction process may contribute to increased erosion. The removal of some native vegetation in the buffer zone. Native vegetation has already been removed near the structures and replaced by native grasses and lawn. More will be removed in order to replace the existing house, replace drainage pipes, and replace the drainfield. There may be soil impacts from the movement of construction equipment vehicles on the Site. The project will increase the impervious surface on the Site. The overall footprint of the house is expected to increase by about 1,250 square feet. The deck will be permeable and will not affect the amount of impervious surface. The historical removal of native vegetation from the Site has already resulted in the direct loss of some habitat. Many species of bird, small mammal and insect use native plants for food sources and refuge. Further loss of vegetation in the buffer zone could reduce habitat for these organisms. The Management Plan below is intended to offset these adverse impacts. The Mitigation Measures developed in this Plan are intended to compensate for the impacts to the shoreline habitat and buffer zone. VJW1473-OlympusBlvdHMP.RPT/041116/mas 14 3.4 PLAN COMPONENTS The components of the Mitigation Plan include the following: Erosion control methods will be used to prevent on -Site rill or sheet erosion from moving sediments toward the adjacent shoreline. This will be accomplished through project timing and emplacement of control measures during construction. A sift fence will be placed on the edges of the construction area, adjacent to the construction envelope and between the construction and the shoreline (see Zenovic & Associates 2016). The large trees along the northern site boundary which do not interfere with construction will be retained. Native vegetation will be planted in two main areas, one area east of the new house and one area near the residence to mitigate disturbance to existing plants in the buffer zone. The drainfield area will be revegetated using native grasses. No nutrients, pesticides or other contaminants will be used within 100 feet of the shoreline. 3.5 DETAILED MITIGATION MEASURES The detailed Mitigation Measures corresponding to the Plan Components listed above are as follows: Timing of construction, as feasible, should be limited to the "dry season" between May 1 and September 30. By limiting construction to this time period, less effort will be required to inhibit erosion and silt runoff. All graded areas should be covered or re -vegetated prior to November 1. If it is necessary to continue construction into the "wet season," then extra measures will be required for erosion and silt runoff control as per recommendations by Zenovic & Associates (2010 and 2016). All erosion control measures should be installed prior to beginning grading or other ground -disturbing construction activities. A silt fence will be placed between the residence structure and the beach. This should be kept in place until plantings and new grasses have become established. Straw bales, jute netting or other material should be kept on -Site and used to stabilize open areas following grading. W W 1473-OtympusBlvdHMP.RPT/041116/mas 15 Three areas within the buffer zone will be re -vegetated with native plant species as per the Planting Plan described in Chapter 4.0 in order to reduce future erosion and enhance buffer function. Planting success will be monitored and will conform to performance standards as described in Sections 3.6 and 3.7. If performance standards are not met, additional plantings or other remedial actions will be taken to meet standards as per requirements in Section 3.7. Large conifers along the northern site boundary will be retained. Implementation of these Mitigation Measures is anticipated to mitigate impacts associated with the further development of the Site and disturbance to the buffer zone. However, the narrow size of buffers at this site and the limited filtering capacity of sandy soils will limit the extent to which the Site will filter long-term pollution and sediments entering the adjacent waters. To minimize the potential for contaminants to enter these waters, no additional nutrients, pesticides or additional contaminants should be used on the Site within 100 feet of the OHWM. 3.6 IMPLEMENTATION AND TIMING The continuation of construction on the Site should be conducted between May 1 and September 30 as feasible, in order to minimize ground -disturbing activities during the rainy season. Any work carried out during the rainy season should have all erosion control measures in place prior to beginning. New plantings in the buffer zone should be carried out during early fall if possible (September -October) to avoid the necessity of supplemental watering. Plantings can be placed during the winter or early spring (March -May) if necessary. If plantings occur during summer months, supplemental watering with a drip irrigation system or equivalent method may be necessary. Westech recommends that monitoring of plantings be conducted by a landscaping firm, certified arborist, registered nursery or qualified botanists and that success of plantings be maintained above a performance standard of 90 percent (see Section 3.7). 3.7 MITIGATION MONITORING Buffer areas serve a variety of functions. They are important in that they reduce the adverse impacts of adjacent land uses by stabilizing soil and preventing erosion; filter suspended solids, nutrients and toxic substances; moderate impacts of stormwater runoff; and reduce noise disturbance and light intrusion. They can also provide important habitat for wildlife. W W1473-olympu$BlvdHMP.RPT/041116/mas 16 The narrow size of buffers at this Site (about 75 feet from OHWM to the house) and the limited filtering capacity of sandy, gravelly soils limit the extent to which the Mitigation Measures will fitter pollution and sediments from ongoing activity. This can include pollutants from hydrocarbons, heavy metals, pesticides and fertilizer. Literature on buffer size indicate that buffers of 100 feet may be necessary to consistently filter sediments and pollution that occur in stormwater runoff (Wenger 1999, Mayer at al. 2005). Precluding the use of pesticides, nutrients and other potential contaminants within 100 feet of the OHMW will limit the impact of these pollutants on nearshore critical habitat. The literature also indicates that plantings can increase the effectiveness of the buffer zone, or decrease the size needed to filter contaminants. Because buffer zones serve several functions, it is important that the Mitigation Measures that are implemented to offset significant impacts are successful. Monitoring over an extended period of time provides the best assurance of success. Monitoring success of erosion control measures during construction will be carded out daily during construction. Any evidence of erosion or sedimentation leaving the construction area (particularly during or after stone events) will result in immediate action to block erosion and sediments. Such siltation can be blocked through the use of additional silt fences, straw bales, wattles, or temporary berms. Monitoring the success of new native plants (as per the Planting Plan described in Section 4.0) should be carried out and enforced by the County according to the following schedule and performance standards: Following construction, the areas shown in the Planting Plan (Section 4.0) should be replanted. The coverage of replanted native vegetation should remain at 90 percent of the original area planted. If monitoring indicates that viable vegetation drops below this level in the planting areas, contingency measures must be implemented. The homeowners should have a monitoring report prepared by a qualified professional at the and of the first growing season. Follow- up monitoring reports should be completed at the end of the second and third full years after construction and restoration. These reports should address the success of the plantings. Any plant mortality should be noted and corrected if plant survival falls below 90 percent during the first three years. Documentation should include any necessary corrective measures that include supplemental planting to compensate for plant mortality and notation of the apparent reasons for such mortality. All reports should be submitted to Jefferson County for review and concurrence. W W1473-OlympusBlvdHMP.RPT/041116/mas 17 For this plan to be successful, the County must monitor compliance with its conditions. The failure of the County to monitor the implementation of the Plan may lead to its ineffectiveness. 3.8 CONTINGENCY PLAN A Contingency Plan should be prepared and followed if Mitigation Measures appear to be failing. This plan, if necessary, should address any mortality affecting revegetated areas having plant survival below the 90 percent level at the end of any season during the three year monitoring period. Should this performance level not be met, the Contingency Plan should include an assessment of the reasons for failure by a qualified botanical professional and the plan should include the introduction of plants likely to be successful in the location where performance standards were not met. WW1473-OlympusBlvdHMP.RPT/041116/mas 18 4.0 PLANTING PLAN A Planting Plan as diagrammed in Figure 6 will be implemented to mitigate for the disturbance of native vegetation in the buffer areas. Plantings have been proposed to offset construction of the drainfield area and for work on storm drainage. A list of native plants that will be used for mitigation and restoration can be found in Table 1. Revegetation and planting of additional vegetation will occur as an integral part of the Project to compensate for environmental impacts caused by the ground - disturbing activity. Most of the area immediately adjacent to the location of the proposed residence expansion, stormwater pipe replacement, and septic system modification is grassy lawn and shrubs. New native grass -seed mixture should be used to replant the construction area upon completion of the new house, where stormwater drainage work will occur and where the new septic drainfield area will be placed, upon completion of those activities. The areas designated for additional plantings include: Planting Area A is a 30 foot by 50 foot area adjacent to and landward of the existing Top of Bank on the east side of the parcel. The area is presently covered by low-cut mixed grasses and forbs (lawn). This area should be planted with the mix of shrubs and ground cover found in Table 1. Plants may be clustered so as to leave one pathway to the bank and beach. Planting Area B is an approximately a 9 foot by 50 foot area that will be planted south of the house. This area is presently vegetated by mixed grasses, (orbs and shrubs which will be removed during construction. This area should be planted with a mix of selected low shrubs and groundcover (Table 1). These plants should be planted in similar patterns as Area A. Planting area C will be the 28 foot by 43 foot area where the new dreinfleld will be installed. This area will include planting of a native grass seed mix to minimize erosion and enhance the buffer zone. Success of the planting plan depends on choosing species that are suitable to both the on -Site soil conditions, but that are hardy and capable of handling nutrient poor soils, shading and some salt spray. The native vegetation selected for this Mitigation and Habitat Management Plan were chosen for these reasons. W W1473-OlympusBlvdHMP. RPT1041116/mas 19 ss N N T N N N d V E o U �+ otS ss ta� 7A '1 N 8.)IAONI WEI .c � ,�6�n ! �a� bei �z z•�#X s � �g c z u Od n ppn cy m iIF3 E N` �i Cryy ./ \., yr. ag rn / $€pE r•` me espy nye �r� LL `Y• �� � � � sly •Sad 4 &., .e:G rh _451fi444 \ , aASI .. 6§ K ApApp 'fYQ §9pp ��z#easpp SjI VI.'kISCV7 ix % wa iiusrv; r L� i4 q' ,,,€fff���ppp`r* i'�\QV..�.j� -pN l k pfiflT ;v dMfanl)»� a�R3.0 TABLE 1. LIST OF NATIVE PLANTS FOR BUFFER MITIGATION AND ENHANCEMENT Location S ecies Scientific Name Number Size A Salal Gaultherin shallon 5 1 gallon A Oregon Grape Mahonia nervosa 12 4" pot A Bracken fern Pte» dfum a utlinum 15 1 gallon A Snowberry S m horocar us albus 12 1 gallon A Red Elderbeny Sambucus racemosa L 10 1 gallon A Indian Plum Oemleria cerasiformis 8 1 gallon A Sword fern Polys Urn mumitum 20 1 gallon .._ B Salal Gaultheriashallon 10 1 gallon B Kinnikinnick Aro 10 1 gallon B Vine Maple mva-ursi A 5 1 gallon B Oceans ra _ _ _ - - Holodiscus discolor 8 1 gallon B C L Sword fern Nativegrass seed mix Polystichum mumitum Grarmnae 5 20 1 gallon --oounds VWJ1473-01ympusB1vdHMP Tabl/641216/mas 21 Soils on the Site are mostly gravelly loams and sandy gravelly loams which are moderately well drained. Normal rainfall will quickly drain through these soils. Plants may require additional watering during the first year or two in order to meet performance criteria. A simple drip irrigation system would be the most effective method of accomplishing this. The species, size and number of plants that will be used to revegetate these areas is shown in Table 1. Plants will be placed in a semi -random fashion within the areas indicated in Figure 6. Large trees, where recommended, should be placed on 10 - foot centers. Small trees will be placed on eight -foot centers (oceanspray and Indian plum) and shrubs will be planted on six-foot centers or less. Staggering of plants, rather than planting in straight rows, will create a more natural appearing configuration. Plants may be clustered by species in order to promote natural reseeding. Plants installed in the fall usually out -perform those installed in the late winter or spring. Planting projects scheduled for early October to mid-December are generally the most successful. The earlier plants go into the ground in the fall, the more time they have to recover from transplant shock, adapt to the site, and expand their roots systems before the growing season. They will require less water and grow more vigorously than if they are planted in the spring. To increase the potential for the planted species to survive, four inches of mulch should be placed around the installed plants with the mulch two inches away from the stem of the plants. VWJ1473-OlympusBlvdHMP.RPT/041116/mas 22 6.0 CONCLUSIONS AND RECOMMENDATIONS 5.1 CONCLUSIONS The property presently contains an existing home, with a covered porch (deck), and septic-drainfield system, within the buffer zone. The residence will be replaced by demolition of the existing residence and construction of a 1,868 square snot home roughly on the existing footprint. A new pervious deck (652 square feet) and a new septic system and drainfield will also be added. The property owner also intends to construct storm water drainage lines adjacent to the house as recommended by Zenovic & Associates 2016). Replacement of the existing septic system will be made as per the septic permit issued by Jefferson County. The proposed project is being constructed inside the buffer zone, though the proposed structure will be only slightly closer to the shoreline than has previously been the case (roughly 75 feet from OHWM). Measures outlined in this report will be enacted to mitigate additional construction on the Site and incrementally improve habitat and vegetation in the nearshore area. Erosion control measures will include a sift fence and other standard measures and will be used during construction to minimize sheet and rill erosion (see also Zenovic & Associates 2010, 2016). A Planting Plan (See Figure 6 and Table 1) will be implemented to provide additional vegetation adjacent to the shoreline, and south of the house. Also, ivy and any other invasive, non-native plants should be removed from the buffer zone. This report and associated Habitat Management Plan meets the intent of RCW36.70A.480 ensuring "No Net Loss of Shoreline Ecological Function" due to the Mitigation proposed, and applicable Jefferson County Codes. 5.2 RECOMMENDATIONS This report constitutes a Mitigation and Habitat Management Plan. A Planting Plan has been included in this report and we recommend that it be implemented on the Site upon approval by the County. Benefits deriving from this Plan will only take place if it is implemented by the property owners and enforced by the County. The silt fence should be emplaced prior to construction and should be left in place throughout construction. Additional erosion control materials should be kept on Site to address any erasion observed during construction. The Planting Plan outlined in this report should be implemented. The Plan should be monitored according to the instructions outlined in this report and the Contingency Plan implemented in the event that plant survival in the revegetated areas falls below 90 percent. W W1473-OlympusBlvdHMP.RPT/041116/mas 23 Property owners should refrain from the use of pesticides or additional nutrients on the Site and should introduce no contaminants within 100 feet of the OHWM. While these measures will provide mitigation for additional construction and use of the Site, the shoreline and marine critical areas may experience continued cumulative impacts as a result of the narrow size of the buffers and limited filtering capacity of the soils in this area. WVV1473-olympusBlvdHMP. RPT/0411161mas 24 6.0 CERTIFICATION I, the undersigned, certify that the infonnatlon contained in this Mitigation and Habitat Management Plan for Assessor's Parcel #978-900-016 in Jefferson County, California located at 460 Olympus Boulevard, Port Ludlow, Washington is true and correct to the best of my knowledge and professional judgment. The project has been performed by myself and other staff and associates of Westech Company. Dr. G. Bradt rd Shea, Principal Dat€ Senior BiologistfEcologist vvW1473-01ympus61vdHMP.RPT10411161mas 25 7.0 REFERENCES Google Earth. 2016. Online mapping software. www.googleearth.com. Imagery date April 19, 2015. Europa Technologies. Jefferson County. 2016a. Online Map Database. http://vrww.co.jefferson.wa.us/. Jefferson County, Washington. Jefferson County Shoreline Master Program. 2016b. Shoreline Master Program; Chapter 16.25. www.codepublishinci.com. Jefferson County. 2016c. On -Site Sewage Disposal Permit. Permit # SPE15- 00112. Jefferson County Public Health Department. Port Townsend, Washington. Jefferson County. 2012. SPAADSite Plan Approval Advanced Determination for Residential Development. Jefferson County DCD. Port Townsend, Washington. Jefferson County. 2009. Jefferson County Critical Areas Code. Title 18.22 JCC. Department of Community Development. Port Townsend, Washington. Hitchcock, C.L. and A. Cronquist. 1973. Flora of the Pacific Northwest. University of Washington Press. Seattle, Washington. Lyons, C.P. 1997. Wildflowers of Washington. Lone Pine Publishing. Renton, Washington. Martin, D. 2015. On -Site Sewage Disposal System, Site Plan. David Martin, Licensed Designer. Plans and specifications. Jefferson County, Washington. Mayer, P.M., S.K. Reynolds, and T.J. Canfield. 2005. Riparian Buffer Width, Agency. Natural Resource Conservation Service (NRCS). 2016. Web Soil Survey. http://Websoilsurvey.nrcs.usda.gov/app/HomePage.htm Pojar, J. and A. MacKinnon. 1994 (reprinted 2004). Plants of the Pacific Northwest Coast. Lone Pine Publishing Company. Redmond, Washington. Rankin, J.L., Architect. 2015. Site plans for 460 Olympus Boulevard, Port Ludlow, Washington. Normandy Park, Washington. WN1473-01ympus131WHMP.RPT/041116/mas 26 Revised Code of Washington. 2016. RCW36.70A.480. Shoreline of the State. hftp://apps/leg.wa.pov/rcw/defau ft.aspix?cite=3670A.480. Taylor, R. 1995. Northwest Weeds. Mountain Press Publishing Company. Missoula Montana. Wegner, S. 1999. A Review of the Scientific Literature on Rioarian Buffer Width. Extent and Veoetabon. Athens, Georgia, Institute of Ecology, University of Georgia. Zenovic & Associates. 2016. Drainage Plan for SFR at 460 Olympus Boulevard, Jefferson County Parcel 978-900-016. Designed for Thomas Balzarini. Port Angeles, Washington. Zenovic & Associates. 2010. Geotechnical Review Report for Property at 460 Olympus Blvd. Mats Mats Bay Area, Jefferson County, Parcel No. 978-900- 016. Stephen M. Zenovic, P.E. PortAngeles, Washington. W W1473-0IympusBlvdHMP.RPTtO41116/mas 27 APPENDICES WJtl1473-OlympusBlvdHM P. RPT/041116/mas 28 APPENDIX A SITE PHOTOGRAPHS W W1473-Olympu$BlvdHMP.APPA/041210/mas A-1 .. �rffl W W1473-OlympusBIVdHMP APPA/041216/mas A-3