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HomeMy WebLinkAboutAppx B 10-04766-065_Wtld-Strm Bffr Mitgtn 150623 DRAFT WETLAND AND STREAM BUFFER MITIGATION REPORT BLACK RIVER PUMP STATION SEDIMENT REMOVAL PROJECT Department of Natural Resources and Parks Water and Land Resources Division WETLAND AND STREAM BUFFER MITIGATION REPORT Black River Pump Station Sediment Removal Project Prepared for Department of Natural Resources and Parks Water and Land Resources Division King Street Center – DNRP 201 South Jackson Street, Room 700 Seattle, Washington 98104-3855 by Herrera Environmental Consultants, Inc. 2200 Sixth Avenue, Suite 1100 Seattle, Washington 98121 Telephone: 206-441-9080 June 23, 2015 DRAFT Prepared by: George Ritchotte, Herrera Environmental Consultants, Inc. For comments or questions contact: George Ritchotte, 206-787-8288 Alternate Formats Available 206-296-7380 TTY Relay: 711 i kg 10-04766-065_wtld-strm bffr mitgtn 150623.docx CONTENTS Introduction ................................................................................................. 1 Regulatory Implications ................................................................................... 3 City of Renton Regulations .......................................................................... 3 Mitigation Sequencing ................................................................................ 3 Impacts and Mitigation .................................................................................... 5 Existing Conditions .................................................................................... 5 Impacts ................................................................................................. 5 Buffer Mitigation and Vegetation Management Plan ............................................. 7 Goals, Objectives, and Performance Standards ........................................... 8 Buffer Revegetation Plan ..................................................................... 8 Monitoring, Site Maintenance, and Contingency Plan ................................... 10 References ................................................................................................. 13 APPENDICES Appendix A Photos Appendix B Planting Plan TABLES Table 1. Stream and Wetland Buffer Impact Areas. ................................................. 7 Table 2. Plant Species Planned for Buffer Restoration. ............................................. 9 FIGURES Figure 1. Vicinity Map for the Black River Pump Station Sediment Removal Project, Renton, Washington. .......................................................................... 2 Figure 2. Black River Pump Station Sediment Removal Project Stream and Wetland Buffer Impacts. ................................................................................. 6 June 2015 DRAFT Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project 1 I NTRODUCTION The King County Department of Natural Resources and Parks Water and Land Resources Division (King County) operates the Black River Pump Station (pump station) to provide flood control in the lower Green River Valley. The pump station is located on the Black River in the City of Renton, Washington, about 1,700 feet upstream from the confluence of the Black River and Green River (Figure 1). King County proposes to temporarily divert Black River flow through a bypass pipe on the north side of the river and dredge approximately 2,900 cubic yards of sediment that has accumulated behind the pump station. Sediment will be stockpiled and dewatered on the south side of the Black River before disposal at an offsite facility. Project construction would entail: • Staging and site preparation, which will include constructing a sediment stockpiling, decant and treatment area and crane pad • Isolating the in-water work area with turbidity curtains, cofferdams, temporary flow diversion structures, or other best management practices (BMPs) • Excluding fish from the in-water work area • Placing sediment removal equipment in the work area using the crane • Removing and stockpiling sediment adjacent to the river • Decanting stockpiled sediment and treating the wastewater • Removing in-water BMPs • Hauling sediment off site • Restoring and replanting any cleared areas A detailed project description can be found in the Biological Evaluation and Habitat Data Reports prepared for the project (Herrera 2014a, 2014b). Despite revisions to project design to reduce environmental impacts, and implementation of minimization and avoidance measures, the project will result in unavoidable impacts to the Black River, the regulatory buffer of the Black River, and wetland buffers. The staging and stockpiling area, and an access road extending from the staging area to the streambank, will be located within the regulatory buffers of both the Black River and wetlands located on the south side of the river, resulting in combined stream and wetland buffer impacts on the south side. The bypass pipe will need to cross the buffers of the Black River and a wetland on the north side of the river. Minor clearing to set the pipe may cause combined wetland and stream buffer impacts on the north side. All impacts will be temporary, and cleared areas will be revegetated with native vegetation once construction is complete. This report documents City of Renton regulatory requirements, avoidance and minimization measures that were incorporated into project design and construction methods, unavoidable buffer impacts, and compensatory mitigation for those impacts. Seattle Renton Renton Tukwila SeaTac §¨¦405 §¨¦5 UV900 UV900 UV167 UV181 UV167 P anther CreekBlackRiver Springbrook CreekGreenR iv e r DuwamishRiver K:\Projects\Y2010\10-04766-018\Project\Mitigation_Report\vicinity_map.mxd (6/12/2015) 0 2,000 4,0001,000 Feet Legend Project area Stream or river Road Highway Railroad City limit ^ P A C I F I CO C E A N BRITISH COLUMBIA WASHINGTON Olympia Bellingham MountVernon DarringtonPortAngeles EverettForks Index SeattleBremerton Leavenworth Shelton Cle ElumOceanShores Chehalis Tacoma USDA, Aerial (2013) Figure 1. Vicinity Map for the Black RiverPump Station Sediment Removal Project,Renton, Washington. June 2015 DRAFT Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project 3 R EGULATORY IMPLICATIONS City of Renton Regulations Wetlands in the study area are within the Black River shoreline and fall under the jurisdiction of the City of Renton’s Shoreline Master Program (SMP) (Redmond Municipal Code [RMC] 4-3-090). The SMP requires that wetlands within shoreline jurisdiction be classified according to the Washington State Department of Ecology (Ecology) rating system (Hruby 2004). Buffers are required around each wetland in order to protect the wetland functions and values. Wetland B is a Category III wetland with a minimum buffer width of 75 feet. Wetland C is a Category IV wetland, and has a buffer of 50 feet. Wetland D, also a Category III wetland, has a buffer of 125 feet. According to RMC 4-3-090 B.3.a, the jurisdictional area associated with shorelines include lands within 200 feet from the ordinary high water mark or lands within 200 feet from floodways, whichever is greater. Per RMC 4-3-090 D.2, shoreline use and development shall be carried out in a manner that prevents or mitigates adverse impacts to ensure no net loss of ecological functions and processes of wetlands, including buffers. According to RMC 4-3-090 D.2.d.x, activities that adversely affect wetlands or buffers shall follow mitigation sequencing, as described below, to ensure that impacts on wetlands and buffers are minimized to the extent feasible. In addition, RMC 4-3-090 F.3.d.viii(c) states that no dredged material shall be stockpiled in a shoreland area that would result in the clearing of native vegetation. Mitigation Sequencing This project has made all reasonable efforts to provide sufficient mitigation such that the project will not result in net loss of buffer functions. The following describes the mitigation sequencing approach as required by RMC 4-3-090 D. 21 and the corresponding measures taken by the project to comply with these requirements: • Avoiding the adverse impact altogether by not taking a certain action or parts of an action, or moving the action. o The project completely avoided wetland impacts by moving the proposed staging area from the north side to the south side of the Black River. Completely avoiding stream and wetland buffer impacts was not feasible due to the amount of space eneded for the staging and sediment treatment area. Because accumulated sediments are within the stream channel, completely avoiding stream impacts was also unavoidable. 1 This mitigation sequence is also outlined in joint Ecology, US Army Corps of Engineers, and US Environmental Protection Agency guidance (Ecology et al. 2006); and State Environmental Policy Act (Washington Administrative Code Chapter 197-11-768). June 2015 4 DRAFT Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project • Minimizing adverse impacts by limiting the degree or magnitude of the action and its implementation by using appropriate technology and engineering, or by taking affirmative steps to avoid or reduce adverse impacts. o The staging area was sized and located to minimize buffer impacts to the extent possible. The staging area was sited to avoid the drip line of any large trees. o Tree clearing has been avoided to the extent possible. o No native vegetation will be cleared for staging and stockpiling. Staging and stockpiling will take place on the parking lot and maintained lawn immediately east of the lot. o Bypassing and dewatering the excavation area will minimize turbidity. • Rectifying the adverse impact by repairing, rehabilitating, or restoring the affected environment. o All areas disturbed by project activities will be revegetated with native plant species as part of the Buffer Mitigation and Vegetation Management Plan (see section below). • Reducing or eliminating the adverse impact over time by preservation and maintenance operations during the life of the action. o The project will minimize adverse impacts on buffer areas over time by revegetating disturbed areas immediately following construction. Lawn that is currently dominated by nonnative grass will be revegetated with native shrub and emergent vegetation. o The Monitoring, Site Maintenance, and Contingency Plan (see section below) will ensure that performance standards for buffer planting areas are achieved and buffer functions are restored. • Compensating for the adverse impact by replacing, enhancing, or providing similar substitute resources or environments, and monitoring the adverse impact and taking appropriate corrective measures. o Cleared areas will be revegetated at a 1:1 ratio. Nonnative vegetation such as Himalayan blackberry (Rubus armeniacus), reed canarygrass (Phalaris arundinacea,) and Kentucky bluegrass (Poa pratensis) will be replaced with appropriate native species. Because the project will cause unavoidable temporary buffer impacts, a buffer mitigation and vegetation management plan is provided in this report. June 2015 DRAFT Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project 5 I MPACTS AND MITIGATION Existing Conditions Project activities will occur on the north and south sides of the Black River, as well as within the Black River channel. On the south side of the river in the project area a narrow strip of riparian vegetation approximately 60 feet wide extends along the bank, which rises steeply from the river to a flat grassy area immediately east of the pump station parking lot. Two wetlands (wetlands B and C) were delineated on the south side of the river for this project (Herrera 2014c). Wetlands and streams in the project vicinity are described in the Wetland and Stream Delineation Report (Herrera 2014c). The proposed access road will extend from the pump station parking lot to the riverbank through the vegetated strip (Figure 2). Plant species in this location are primarily willows (Salix spp.), red osier dogwood (Cornus sericea), red alder (Alnus rubra), Douglas-fir (Pseudotsuga menziesii), shore pine (Pinus contorta), and black cottonwood (Populus balsamifera). Himalayan blackberry (Rubus armeniacus) and reed canarygrass (Phalaris arundinacea) dominate the understory (Appendix A, Photo 1). The staging and dewatering area will be constructed in the grassy area south of the riparian strip. Vegetation in this area is almost entirely nonnative Kentucky bluegrass (Poa pratensis). One large shore pine, which is 15 inches diameter at breast height (dbh) grows in the middle of the lawn (Appendix A, Photo 2). The north bank rises steeply from the riverbank to a flat area level with the top of the pump station where the access road and some pump station infrastructure are located. Two wetlands (wetlands A and D) were delineated on the north side of the river, north and east of the proposed bypass pipe alignment. Soils consist largely of imported cobbles and gravel fill. Reed canarygrass, Himalayan blackberry, tansy (Tanacetum vulgare), and other nonnative herbaceous vegetation are the dominant plant species in this area. There is very little native vegetation (Appendix A, Photo 3). Downstream of the pump station the stream bank is heavily riprapped. Himalayan blackberry has spread over the rocks (Appendix A, Photo 4). On the upstream side of the station a concrete wingwall extends along the bank for approximately 30 feet. Yellow flag iris grows thickly along the shoreline (Appendix A, Photos 5 and 6). Impacts The total area needed for the south staging and access road is approximately 13,359 square feet. However, of that total area, 4,593 square feet of that area is gravel parking lot; thus there will be 8,766 square feet of vegetation clearing. Most of the cleared area is within the 200-foot regulatory buffer of the Black River, and overlaps with portions of the buffers of Wetlands B and C (Figure 2; Table 1). K:\Projects\Y2010\10-04766-065\Project\Mitigation_Report\stream_wetland_buffer_impacts.mxd (6/19/2015) 0 60 12030Feet Legend Staging area Wetland and stream buffer impact Stream buffer impact Wetland buffer impact Wetland buffer Delineated wetland Bing, Aerial (2014) Figure 2. Black River Pump Station SedimentRemoval Project Stream and WetlandBuffer Impacts. June 2015 DRAFT Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project 7 Table 1. Stream and Wetland Buffer Impact Areas. Impact Type Impact Area (sq. ft.) Access Road Wetland C and stream buffer 528 South Staging Area Stream buffer only 1,171 Wetland B and stream buffer 3,825 Wetland B buffer only 2,856 Combined wetland B, C, and stream buffer 386 Bypass Pipe Alignment Stream buffer only 3,738 Wetland D and stream buffer 10,019 The south side staging and stockpiling area covers 8,104 square feet, and covers buffers of the Black River, Wetland B, and Wetland C. Vegetation is almost entirely maintained lawn dominated by nonnative Kentucky bluegrass. One 15-inch dbh shore pine in the middle of the lawn will need to be removed. Except for removal of that tree, no native vegetation will be cleared for stockpiling. The access road area is approximately 528 square feet. Several small (2- to 4-inch dbh) red alders and two small (2-inch dbh) Douglas-firs will be removed to construct the road (Appendix A, Photos 7 and 8). As much as 13,757 square feet of stream and Wetland D buffer vegetation will be cleared within the bypass pipe alignment (Table 2). Almost all the vegetation within this area consists of nonnative weedy species (Appendix A, Photos 9 and 10). No trees, shrubs, or native woody vegetation will be removed. All buffer impacts will be temporary and will be restored post project per the buffer mitigation plan described below. Buffer Mitigation and Vegetation Management Plan According to RMC 4-3-090 D.2.d.xii, a vegetation management plan is required in order to maintain effective buffer conditions and function. Supplemental planting may be necessary to provide adequate cover of native vegetation. In addition, the plan needs to include measures for controlling invasive weeds and removal of existing invasive species. The plan also needs to include a monitoring and maintenance plan for a period of at least 5 years. This plan will ensure that buffer areas are restored to their pre-existing condition or better (such as reduction of invasive species coverage), resulting in no net loss of ecological functions in buffer areas. Per RMC, 4-3-090 D.2.d.x(e), the minimum mitigation ratio for buffer impacts is 1:1 (i.e., the area of buffer revegetation must equal the area of buffer impact). The project will enhance existing buffer by replacing the existing maintained lawn with native buffer vegetation. June 2015 8 DRAFT Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project Goals, Objectives, and Performance Standards The goal of the mitigation plan is to rectify temporary buffer impacts by restoring buffer function through restoration of buffer vegetation, resulting in no net loss of buffer area or ecological function. The objective is to establish a diversity of native emergent and shrub species in buffer restoration areas that will develop into a mature vegetation community with adequate cover and comprised of native plant species. The project will accomplish the goal and objective of the mitigation plan by implementing the following performance standards. • Year 0: 100 percent of planted species will survive by the end of the first year after planting. Plants that die will be replaced. All plants will be installed as specified in the mitigation plan to achieve intended plant community composition and structural diversity. • Year 1: By the end of the second year growing season, native vegetation cover will be at least 20 percent. • Year 2: By the end of the third year growing season, native vegetation cover will be at least 40 percent. • Year 3: By the end of the fourth year growing season, native vegetation cover will be at least 60 percent. • Year 4: By the end of the fifth year growing season, native vegetation cover will be at least 80 percent. • All years: The percentage of the buffer mitigation areas covered by invasive and nonnative species will not exceed 15 percent throughout the monitoring period. Buffer Revegetation Plan The general construction sequence for construction activities in buffer mitigation areas is as follows: • Installation of temporary erosion and sediment control measures per plans and specifications • Site clearing and grubbing per plans and specifications (selective removal of invasive plant species and retention of native species where possible) • Site excavation per plans and specifications • Replacement of topsoil • Installation of weed-free wood chip mulch in the planting areas • Installation of native plant material per project plans and specifications June 2015 DRAFT Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project 9 Planting is scheduled to occur during the dormant, or non-growing, season (October 2015). Because stream access may be needed for future dredging projects, only shrubs and herbaceous species are proposed for planting, to minimize removal of woody vegetation in the future. Shrubs will be planted 4 feet on center, and herbaceous species will be planted 18 inches on center. Plants will be, at minimum, in 1-gallon containers. Plant material will be inspected by the project biologist, botanist, or horticulturist before acceptance, and that person will be on site during replacement of topsoil and plant installation to ensure that topsoil and plants are installed properly. A variety of native emergent and shrub species will be planted in the buffers (Table 2). Species adapted to wetter conditions will be planted in the access road area adjacent to the river. Species more tolerant of drier, sunnier conditions will be planted in the staging area. Many of these plant species currently occur on site, providing a reference for planting prescriptions. The selected species are common in western Washington riparian forest habitat, provide good forage and cover resources for fish and wildlife, and perform well in restoration sites (Stevens and Vanbianchi 1993). Plants with narrow ecological tolerance ranges or that are difficult to obtain from local native plant nurseries were not selected. The mitigation planting plan is included in Appendix B. Table 2. Plant Species Planned for Buffer Restoration. Common Name Scientific Name Stratum Wetland Indicator Status Access Road Red osier dogwood Cornus sericea Shrub FACW Pacific ninebark Physocarpus capitatus Shrub FACW Nootka rose Rosa nutkana Shrub FAC Sitka willow Salix sitchensis Shrub FACW Woodland strawberry Fragaria vesca Herbaceous FACU Sword fern Polystichum munitum Herbaceous FACU Fringecup Tellima grandiflora Herbaceous FAC Piggyback plant Tolmiea menziesii Herbaceous FACU South Staging Area Serviceberry Amelianchier alnifolia FACU Beaked hazelnut Corylus cornuta Shrub FACU Tall Oregon grape Mahonia aquifolium Shrub FACU Nootka rose Rosa nutkana Shrub FAC Thimbleberry Rubus parviflorus Shrub FACU Elderberry Sambucus racemosa Shrub FACU Snowberry Symphoricarpos albus Shrub FACU Sword fern Polystichum munitum Herbaceous FACU South Staging Area and Bypass Pipe Alignment California brome Bromus carinatus Herbaceous Not listed Blue wild rye Elymus glaucus Herbaceous FACU Red fescue Festuca rubra Herbaceous FAC Regreen sterile wheatgrass Triticum aestivum Herbaceous Not listed June 2015 10 DRAFT Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project There will be no grubbing on the north side of the river, but there may be some minor clearing to lay the bypass pipe. No trees, shrubs, or woody vegetation will be cleared. Any cleared areas will be hydroseeded with a mix of native grasses. Monitoring, Site Maintenance, and Contingency Plan Per RMC 4-3-090 D.2.d.xii, maintenance and monitoring will be conducted to ensure that buffer mitigation goals, objectives, and performance standards are achieved. The maintenance and monitoring program will be conducted for a minimum of 5 years to ensure plants become established and develop adequate native vegetation cover. If monitoring activities determine that performance standards are not being met, contingency measures will be implemented to remedy onsite problems. Monitoring Plan King County will arrange for a qualified biologist to perform monitoring of the buffer enhancement areas to ensure compliance with the performance standards listed above. The site will be monitored annually for a minimum of 5 years following construction. If monitoring results determine performance standards are not being achieved, corrective actions will be taken (see Monitoring, Site Maintenance, and Contingency Plan below). Year 0 Monitoring The monitoring visit at the end of the first growing season following construction will be conducted to establish permanent sampling plots and photograph points (as needed), inspect the plantings, identify mortality, and specify quantities and locations of plants needing replacement (see Year 0 performance standard above). In addition, the site will be inspected for the presence of invasive or exotic plant species (see performance standard for all years, above). Years 1, 2, 3, and 4 Monitoring During the second, third, fourth, and fifth years of monitoring (Year 1 through Year 4), mitigation areas will be evaluated and photographs will be taken from each of the permanent photograph points. At the end of the fifth year growing season (Year 4), if performance standards are not achieved, the monitoring period shall be extended for as many years as necessary until they are achieved. All Years Every year mitigation areas will be monitored for invasive species cover to ensure percentage of the buffer mitigation areas covered by invasive and nonnative species does not exceed 15 percent. Site Maintenance and Contingency Plan Following initial planting, the planting contractor will be responsible for maintaining 100 percent plant survival within the wetland and buffer enhancement areas for a minimum of 1 year as per the planting contract plans. In accordance with the 1-year plant survival guarantee, the contractor will replace plants that have died during the first year. Before plants are replaced, the contractor will consult with the project biologist arranged by King June 2015 DRAFT Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project 11 County to determine why certain species are not surviving and, if necessary, which native plant substitutions are appropriate. In addition, throughout the summer of the first year, the contractor will be responsible for irrigating as frequently as necessary to ensure healthy plant conditions. King County will be responsible for managing the establishment of plants from the second through the fifth year, with the goal of meeting all applicable performance standards listed above. If percent cover requirements are not met, maintenance activities may include, but are not limited to, plant replacement, plant supplement, plant substitution, adjustment of planting layout to reflect specific or changing site conditions, weed control, and installation and adjustment of plant protection devices. An integrated pest management (IPM) approach will be adhered to for invasive species management within buffer mitigation areas (all years performance standard), including limited use of herbicides per RMC 4-3-090 D.2.d.xi. Invasive plant species will be pulled by hand to the extent practical. If herbicides are deemed appropriate for use to control invasive species, only those herbicides approved for use in aquatic ecosystems by Ecology (e.g., Rodeo, Aquamaster) will be selected. Herbicides will be applied by a licensed applicator. June 2015 DRAFT Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project 13 R EFERENCES Herrera. 2014a. Biological Evaluation for the Black River Pump Station Sediment Removal Project. Prepared by Herrera Environmental Consultants, Inc. for King County Department of Natural Resources and Parks Water and Land Resources Division. February 5, 2015. Herrera. 2014b. Habitat Data Report for the Black River Pump Station Sediment Removal Project. Prepared by Herrera Environmental Consultants, Inc. for King County Department of Natural Resources and Parks Water and Land Resources Division. March 2, 2015. Herrera. 2014c. Wetland and Stream Delineation Report. Black River Pump Station Sediment Removal Project. Prepared by Herrera Environmental Consultants, Inc. for King County Department of Natural Resources and Parks Water and Land Resources Division. May 16, 2014. Hruby, T. 2004. Washington State Wetland Rating System for Western Washington — Revised. Ecology Publication 04-06-025. Washington State Department of Ecology. August 2004. Stevens, M.L. and R. Vanbianchi. 1993. Restoring Wetlands In Washington: a Guidebook for Wetland Restoration Planning and Implementation. Washington State Department of Ecology, Olympia, Washington. <https://fortress.wa.gov/ecy/publications/summarypages/93017.html>. Ecology, US Army Corps of Engineers Seattle District, and US Environmental Protection Agency Region 10. 2006. Wetland Mitigation in Washington State – Part 1: Agency Policies and Guidance (Version 1). Washington State Department of Ecology Publication #06-06-011a. Olympia, Washington. March 2006. APPENDIX A Photos June 2015 Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project A-1 Photo 1. Riparian vegetation on the south bank of the Black River. Photo 2. Top of bank along the north edge of lawn where staging and stockpiling will take place. The large shore pine to be removed is in the background, far right. June 2015 A-2 Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project Photo 3. Road on north side of Black River and typical Wetland D buffer vegetation in foreground. Photo 4. Nonnative vegetation on the north bank of the Black River downstream from the pump station. June 2015 Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project A-3 Photo 5. Wingwall and stream bank on the north side of the Black River upstream of the pump station. Photo 6. Yellow flag iris on the north bank of the Black River upstream of the pump station. June 2015 A-4 Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project Photos 7 and 8. Buffer vegetation in the proposed south side access road alignment. June 2015 Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project A-5 Photo 9. Buffer vegetation in the proposed bypass pipe alignment – east of the pump station. Photo 10. Buffer vegetation in the proposed bypass pipe alignment – west of the pump station. June 2015 A-6 Wetland and Stream Buffer Mitigation Report—Black River Pump Station Sediment Removal Project APPENDIX B Planting Plan Figure 1Black River Pump StationSediment Removal ProjectBuffer Revegetation PlanO:\proj\Y2010\10-04766-065\CAD\Dwg\Mitigation Report\Figure 1 - Planting Areas.dwgScale in Feet02550100LEGENDSEEDING AREABYPASS PIPE ALIGNMENTPLANTING AREASOUTH STAGING AREAACCESS ROAD AREA Figure 2Black River Pump StationSediment Removal ProjectPlanting Schedule and DetailsO:\proj\Y2010\10-04766-065\CAD\Dwg\Mitigation Report\Figure 2 - Planting Schedule and Details.dwgSTRATUMSCIENTIFIC NAMECOMMON NAMEWETLANDINDICATORSTATUSPLANTMATERIAL SIZEON CENTER(O.C.) SPACINGTOTAL PLANTQUANTITIESPLANT ZONE QUANTITIESACCESS ROADAREASOUTH STAGINGAREASHRUBAMELANCHIER ALNIFOLIASERVICEBERRYFACU1 GALLON4' O.C.8282SHRUBCORNUS SERICEARED OSIER DOGWOODFACW1 GALLON4' O.C.99SHRUBCORYLUS CORNUTABEAKED HAZELNUTFACU1 GALLON4' O.C.8282SHRUBMAHONIA AQUIFOLIUMTALL OREGON GRAPEFACU1 GALLON4' O.C.8282SHRUBPHYSOCARPUS CAPITATUSPACIFIC NINEBARKFACW1 GALLON4' O.C.99SHRUBROSA NUTKANANOOTKA ROSEFAC1 GALLON4' O.C.91982SHRUBRUBUS PARVIFLORUSTHIMBLEBERRYFACU1 GALLON4' O.C.8282SHRUBSALIX SITCHENSISSITKA WILLOWFACW1 GALLON4' O.C.99SHRUBSAMBUCUS RACEMOSARED ELDERBERRYFACU1 GALLON4' O.C.8282SHRUBSYMPHORICARPOS ALBUSSNOWBERRYFACU1 GALLON4' O.C.8282GROUNDCOVERFRAGERIA VESCAWOODLAND STRAWBERRYFACU1 GALLON2' O.C.5555GROUNDCOVERPOLYSTICHUM MUNITUMSWORD FERNFACU1 GALLON2' O.C.1789551734GROUNDCOVERTELLIMA GRANDIFLORAFRINGECUPFACU1 GALLON2' O.C.5555GROUNDCOVERTOLMIEA MENZIESIIPIGGYBACK PLANTFAC1 GALLON2' O.C.5555PLANT SCHEDULEEXCAVATE SOIL FOR PLANTING TO DIMENSIONSSHOWN. FIRM SOIL AROUND ROOTBALL AND WATERSETTLE. DO NOT LEAVE AIR POCKETS. DO NOTDAMAGE ROOTS DURING PLANTING OPERATIONS24" DIAMETER BARK OR WOODCHIP MULCH RING, KEEP 2"AWAY FROM TRUNK OF PLANTFINISH GRADEREMOVE CONTAINER PRIOR TOPLANTING. DURING PLANTINGOPERATIONS GENTLY LOOSENAND SPREAD ROOTSCOMPRESS SOIL INTO SMALL, FLAT TOPPEDMOUND BENEATH ROOTBALL FOR SUPPORT 6" GREATERTHANROOTBALL ORCONTAINERDEPTHPLANT AT SAMELEVEL AS GROWNIN POTEXCAVATE SOIL FOR PLANTING TO DIMENSIONSSHOWN. FIRM SOIL AROUND ROOTBALL AND WATERSETTLE. DO NOT LEAVE AIR POCKETS. DO NOTDAMAGE ROOTS DURING PLANTING OPERATIONS24" DIAMETER BARK OR WOOD CHIPMULCH RING, 4" THICK LAYER, KEEP 2"AWAY FROM TRUNK OF PLANTFINISH GRADEREMOVE CONTAINER PRIOR TO PLANTING.DURING PLANTING OPERATIONS GENTLY LOOSENAND SPREAD ROOTS AT BOTTOM OF ROOTBALLCOMPRESS SOIL INTO SMALL, FLAT TOPPEDMOUND BENEATH ROOTBALL FOR SUPPORTPLANT AT SAMELEVEL AS GROWNIN POTEXISTING GROUNDMAX.ONE GALLON CONTAINER PLANTING DETAILONE GALLON CONTAINERPLANTING ON SLOPE DETAIL 6" GREATERTHANROOTBALL ORCONTAINERDEPTHSTRATUMSCIENTIFIC NAMECOMMON NAMEWETLANDINDICATORSTATUSPERCENT OF MIXBY SEED COUNTPERCENT OF MIXBY SEED WEIGHTPOUNDS PURELIVE SEED (PLS)PER ACREHERBACEOUSBROMUS CARINATUSCALIFORNIA BROMENOT LISTED3021.1815.68HERBACEOUSELYMUS GLAUCUSBLUE WILDRYEFACU3015.7511.66HERBACEOUSFESTUCA RUBRARED FESCUEFAC304.243.14HERBACEOUSTRITICUM AESTIVUMREGREEN STERILE WHEATGRASSNOT LISTED1058.8443.56BYPASS PIPE AREA AND SOUTH STAGING AREA SEED MIXNOTES:1.REMOVE ANY NOXIOUS AND/OR NONNATIVE WEEDS FROM PLANTING ZONES PRIOR TOPLANTING.2.THE PROJECT REPRESENTATIVE SHALL APPROVE GRADES PRIOR TO MULCHAPPLICATION AND PLANT INSTALLATION.3.PLANT SUBSTITUTIONS ARE SUBJECT TO APPROVAL BY THE PROJECTREPRESENTATIVE.4.PLANTS SHALL BE TAGGED FOR IDENTIFICATION AND APPROVED BY THE PROJECTREPRESENTATIVE PRIOR TO INSTALLATION.5.KEEP PLANTS SHADED UNTIL TIME OF PLANTING. DO NOT LET PLANT MATERIAL SIT INSUN OR DRY OUT BEFORE PLANTING.6.PLANT GROUNDCOVER AND SHRUBS IN CLUSTERS OF THREE, FIVE, AND SEVEN. EACHCLUSTER SHALL BE ONE SPECIES. EVENLY SPACE CLUSTERS THROUGHOUT PLANTZONES. INTENT OF PLANTING IS TO APPEAR NATURAL AND INFORMAL.7.THE PROJECT REPRESENTATIVE SHALL APPROVE PLANT LAYOUT BEFOREINSTALLATION.8.APPLY SEED MIX BETWEEN SEPTEMBER 1 THROUGH OCTOBER 1 AND/OR BETWEENMARCH 1 AND MAY 15.9.INSTALL SHRUBS, AND GROUNDCOVER BETWEEN OCTOBER 1 AND MARCH 1 OF THEFIRST DORMANT SEASON FOLLOWING CONSTRUCTION.