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Home My WebLink AboutHabitat Management Plan and Revision - HMP Habitat Managment Plan - 5/1/2021 f Habitat Management Plan Parcel# 32127-54-00075 & 32127-54-00076 231 E Kilmarnock Rd Shelton, WA 98584 Mason County Report prepared for: Anthony Relgarde 31420 8th PI SW Federal Way WA 98023 -,.-.,k -7-„ -,r, r k30V) /31-LOlJ Prepared by: Rob Nagel 6gn F Philura Ln Shelton, WA 98584 arctosaerial@gmail.com (425) 344-9315 (360) 229-3118 -XARCTOS AERIAL Environmental Consultation I Drone imagery Project: 2021-H M P-008 May 2021 (Revised February 2022) Project: 2021-HMP-008 May 2021 (Revised February 2022) A RCTQS A T A C Table of Contents Overview................................................................................................................1 PropertyDescription..............................................................................................2 Analysis of Potential Impacts.................................................................................3 MitigationMeasures..............................................................................................4 Monitoring .............................................................................................................9 Summary................................................................................................................9 References............................................................................................................10 List of Figures Figure1: Vicinity Map ............................................................................................2 Figure 2: Site Plan with drone imagery..................................................................8 i ARMS Project: 2021-HMP-008 May 2021 (Revised February 2022) AERIAL Habitat Management Plan 32127-54-00075 & 32127-54-00076 231 E Kilmarnock Rd Shelton, WA 98584 Overview T his report details a Habitat Management Plan (HMP) for the above referenced properties in Mason County, Washington. The purpose of this report is to address any potential adverse impacts from constructing a Single-Family Residence (SFR) on each lot within the buffer of a Type-F stream. The Mason County Resource Ordinance (MCRO) requires a 150ft buffer with an additional 15ft building setback for Type-F streams. (see figure 1). However, the Resource Ordinance allows for a reduction in the buer;setback if the lot was legally established buff prior to the effective date of the Resource Ordinance if it is the minimum necessary to allow reasonable use of the property. This report proposes a reduction, in the stream buffer to an averaged 117.5ft with a range of 110ft-125ft. The SFRs are proposed as far from the ordinary high-water mark of the Type-F stream as possible. Mitigation measures have been designed to offset the potential impacts of these activities on the ecological functions of the stream buffer. Mitigation measures include construction BMPs, replanting the ±1,200ft2 drainfield areas with native si it uus, ferns, and ground covers. As well as planting native .3pcCics iiii a C.ui i iuii icu 1,900ft2 mitigation area for both lots. The objectives of this report are as follows: • Identify potential impacts of the construction of the proposed structure within the stream buffer, on the buffer's ecological functions and fish and wildlife habitat. • Determine mitigation measures that would offset those impacts and result in no net loss to ecological functions and fish and wildlife habitat within the remaining buffer. i A RCTOS Project: 2021-HMP-008 May 2021 (Revised February 2022) AERIAL 13 �kc', i Figure 1:Vicinity map of project. Property Description & Project Background The parcels are a combined 0.67 acres in size and located in the SE% of the SE% of section 27, Township 21 North, Range 3 West. The building sites are already cleared of vegetation from past management up to ±120ft of the stream. The SFR on one lot is proposed at ±130ft from the stream, while the other SFR is proposed outside the regulated 150ft buffer. Both houses are proposed 30ft from the public road, which is as close as allowed in the Lake Limerick Community. Past grading on both lots has made the only suitable drainfield locations to be ±100ft from the stream. Both drainfield locations will need to be cleared of native vegetation and are within the stream buffer. The areas cleared will be replanted with native shrubs, ferns, and ground covers after installation of the drainfield components. The Mason C—aunty Resource ordinance requires a 150ft buffer with an additional 15ft structure setback, which encompasses most of the subject properties. This report proposes a reduction of the regulated buffer to 100ft with an additional 15ft structure setback. This buffer reduction is the minimum necessary to afford the property owner with a reasonable use of the lot. The proposed buffer reduction is also compatible with the character of surrounding permitted uses and would not adversely affect traffic circulation. Project: 2021-HMP-008 May 2021 (Revised February 2022) AIRIAL A RCTQS CTID Analysis of Potential Impacts Vegetated buffers serve an important role in protecting critical public resources, as well as fish and wildlife habitat froth adverse Impacts associated with development. Below are the potential adverse impacts to ecological functions associated with the construction of these proposed structures within the stream buffer. - Increased storm-water runoff and erosion impervious surfaces such as roofs and driveways contribute to increase-a' flow of runoff during storm events. This increased flow could contribute to erosion and increased sediment reaching the stream without a proper storm water management plan. Only ±700ft2 of the proposed structures are within the regulated buffer. Construction BMPs have been proposed in the "Mitigation Measures" section of this report below and no significant increase in storm-water runoff is anticipated from these projects. - Stream bank de-stabilization Removal of buffer vegetation and increasing storm water run-off can speed erosion of streambanks and make them unstable. All areas where vegetation removal is proposed will be replanted and straw will be placed over any areas while they are exposed. No increased risk of erosion is anticipated. - Loss of wildlife habitat T lie total development foutprinL from Liiese projects within the buffer is ±3,100ft 2. Mitigation measures include replanting a total of 4,300ft' with native vegetation, which will increase the amount of wildlife habitat adjacent to the building sites and have a net ecological benefit to the stream buffer. - Increased disturbance from noise pollution A temporary increase in noise from construction activities is likely to occur. but activities will be limited to daylight hours, and the projects are located in an area along the stream where human noises are a common ARCTos Project: 2021-HMP-008 May 2021 (Revised February 2022) ALRIAL occurrence. Also, no known nesting sites or individual occurrences of prior ity Habitats aiid Spc^Ci2S have been Idelltlfled hear the project Site. - Increased Solar input The proposed structures are sited in an area with mature conifers that will be left to shade the stream. Native plantings within the mitigation area will benefit the stream by increasing shade and reducing solar input in the long- term. Mitigation Measures To avoid, minimize, and mitigate for the potential adverse impacts identified above, the following have been identified as appropriate measures for this project: - Minimizing/avoiding impact The proposed projects minimize the impact to the stream buffer by limiting the square footage of the structures within the buffer to ±700ft2 and placing them as far from the stream as feasible. The structures will be constructed in an area already devoid of vegetation. - Best Management Practices for construction Construction activities related to this project will be restricted to favorable weather conditions and best management practices for reducing disturbance and erosion will be followed, including placing straw over exposed areas, and erecting silt fencing below the project area. Equipment will be checked daily for leaks and all fuel, lubricant, and chemicals will be stored outside the stream buffer. - Clustering of development All activities related to these projects will be clustered to the extent possible without impacting more of the stream buffer than necessary. Equipment and materials will be parked/stored outside the stream buffer whenever not in use. n Y Project: 2021-HMP-008 May 2021 (Revised February 2022) A AR FRIAL CTQS M - Removal of invasive species All occurrences of noxious weed species observed in the vi%inity Gf ti ie project site and mitigation area will be mechanically removed without the use of chemical herbicides. - Stream buffer re-vegetation A mitigation area of 1,900ft2 plus ±2,400ft2 of drainfield area will be restored with native riparian vegetation through plantings per the planting guidelines described below. The mitigation area to be replanted is an area between the proposed structures, along the lot line between the two properties. The minimum number of trees, shrubs, and ferns/groundcovers to be planted in the 1,900ft2 mitigation area in order to meet the required densities are as follows: -Trees = 18 -Shrubs = 55 -Ferns/groundcovers = 115 Once the mitigation area is established, the lot owners must allow the planted vegetation to grow to the full mature size of the species selected, without pruning or trimming. The mitigation area must also be treated as if part of the regulated stream buffer indefinitely. The area cleared for the drainfields will be replanted with shrubs, ferns, and ground covers after installation of the drainfield components. The minimum number of shrubs, ferns, and groundcovers to be planted in the ±2,400ft2 of area cleared for the drainfields in order to meet the required densities are as follows: vi a uuS — w -Ferns/groundcovers = 150 Any additional landscaping within the stream buffer is required to consist of native plant species typically found in undisturbed riparian areas. Species selected should include common riparian vegetation not 5 A RCTOS Project: 2021-HMP-008 May 2021 (Revised February 2022) AERIAV currently on the property which will result in a net increase in species richness and biodiver sity within the buffer. Planting Guidelines for the Mitigation Area Earthwork Machinery earthwork will be restricted to the minimum necessary in order to implement this plan; planting holes for specified vegetation installation will be hand dug. Native Plantings IUntivn nl-Mntin6c IA/III ho inetolInA XAiithin tha mitigation nron r»rnIlol to thin nrian rif the buffer to achieve the following minimum densities: Trees — i0' on center Shrubs — S' on center Ferns, grasses, and ground-covers —4' on center The plan calls for installing single trees on 10ft centers and single shrubs on Sft centers. Areas between lI will be filled if I with ferns, grasses, or ground-covers of lI 4ft centers. The entire mitigation area should be mulched to prevent any non- native species from establishing within the mitigation area. Exact placement of installed materials will be up to the landscape installer, following the basic 10-foot spacing pattern described above. Volunteer native vegetation can be counted towards the target densities of restoration area at the time of monitoring audits. Native plant species appropriate for the mitigation area include the following: Trees: Western red cedar (Thujo plicata) Douglas fir (Pseudotsuga menziesii) Garry oak (Quercus garryana) Western hemlock (Tsuga heterophylla) Grand fir (Abies grandis) Cascara (Rhomnus purshiana) Pacific crabapple (Malus fusca) 6 A RCTOS Project: 2021-HMP-008 May 2021 (Revised February 2022) AERIAL Serviceberry (Almenlanchier alnifolia) Shrubs: Ocean spray (Holodi.SCug dik6lor) Thimbleberry (Rubus parviflorus) Tall Oregon grape (Mahonia aquifolium) Nootka rose (Rosa nutkana) Salal (Gaultheria shallon) Evergreen huckleberry (Vaccinium ovatum) Snowberry (Symphorocarpus albus) Ferns, grasses, and ground-covers: Sword fern (Polystichum munitum) Bracken fern (Pteridium aquil►num) Tufted hairgrass (Deschampsia cespitosa) All planting should occur during winter dormancy. The optimum time for planting is from November to March. Installation Installation of the prescribed vegetation will be performed by qualified landscapers familiar with planting of native vegetation in natural settings. Installation will be performed only after construction on the property is completed to avoid damage to the plantings. Fertilizing Due to the proximity of the mitigation area to the Hood Canal, NO fertilizer will be used during plant installation or maintenance. Maintenance Maintenance of the installations will be the responsibility of the landscape installer. Maintenance is to include any weeding or watering necessary to ensure plant survival for up to three years after the date of installation. it N E Q1 0 O Q m N tr8S86 yM'uo�la45 M c ` N Q Q o 9L000-bS-LZ LZE Q Z. ?8 SL000-VS-LZ6ZE#19DIed d Ln,� VVV ai ` defy kA IeIUOWuoainu3 al!S C W Ln ,�, no o E 2 i M V7y Q V a 1 µ} co E fm a) N aoO ir S O -tar SO4'oL�J N O fi x i. -x b � r � r G1 'a a A RCTOS Project: 2021-HMP-008 May 2021 (Revised February 2022) ATRIAL Monitoring Following the implementation of the mitigation measures, an annual report will be submitted to the county for J years post construction. The report will detail the presence of new, or the reoccurrence of any invasive species. Invasive species found on site will again be removed mechanically, using hand tools only to reduce disturbance to the shoreline buffer. The annual report will also document the planting success of the mitigation area. If planting survival in the mitigation area falls below 90% in the first three years after installation. The area will be re- planted to meet the target densities. If any failures of mitigation measures are identified during the annual inspection, corrective actions will be recommended in the report and will be taken by the property owner to restore them to working order as soon as possible. Summary This report Identifies potential impacts of the construction of two proposed SFRs, with a combined square footaize of ±700ft2 footprint within a regulated Type-F stream buffer. The proposed building sites are currently devoid of vegetation and provide little benefit to the stream and its buffer. A total of 2,400ft2 within the regulated buffer will need to be cleared for the drainfields of these two SFRs. Mitigation measures have been proposed to avoid, minimize, and mitigate for those impacts identified on the stream buffer's ecological functions and fish and vv11un1c JiauitaL. .Jua.a.%_; iiiiNiciiicii�U1.1 vi 1111 N1vNvacu �i��saLIvii 111caauica will result in no net loss to the stream and its buffer's ecological functions, structural diversity, and sperlPs rirhnasc. Mitigation measures include construction BMrs, re-establishing native vegetation in a 1,900ft2 mitigation area, and replanting the 2,400ft2 drainfield areas after installation of the drainfield components. 9 -Project: 2021-HMP-008 May 2021 (Revised February 2022) ARMS AERIAL References Guard,J. (1995). Wetland Plants of Oregon &Washington. Lone Pine Publishing.240 pp. Edmonton, Alberta, Canada. Pojar,J. and A. MacKinnon. 1994.Plants of the Pacific Northwest Coast(Revised Edition 2014).Lone Pine Publishing.528 pp.Vancouver, British Columbia, Canada. WDFW. 2002. Integrated streambank protection guidelines.Washington Department of Fish and Wildlife,Washington Department of Transportation, and Washington Department of Ecology. Posted on Washington Department of Fish and Wildlife web site: https://wdfw.wa.gov/sites/default/files/publications/00046/wdfw00046.pdf 10 RECEIVES P'LANNING 19 2021 HabitatJZnawment Plan Parcel# 32127-54-00075 & 32127-54-00076 231 E Kilmarnock Rd Shelton, WA 98584 Mason County Report prepared for: Anthony Belgarde 31420 8th PI SW Federal Way WA 98023 (360) 731-2615 Prepared by: Rob Nagel 680 E Philura Ln Shelton, WA 98584 arctosaerial@gmail.com (425) 344-9315 (360) 229-3118 ARCTOS AERIAL. Environmental Consultation I Drone Imagery Project: 2021-H M P-008 May 2021 Project: 2021-HMP-008 May 2021 ARMSAERIAL Table of Contents Overview................................................................................................................1 PropertyDescription..............................................................................................2 Analysis of Potential Impacts.................................................................................3 MitigationMeasures..............................................................................................5 Monitoring ...........................................................................................................11 Summary..............................................................................................................11 References............................................................................................................13 List of Figures Figure1: Vicinity Map ............................................................................................2 Figure 2: Map depicting parcel & buffers...............................................................3 Figure 3: Site Plan with drone imagery................................................................10 i Project: 2021-HMP-008 May 2021 ARMS Habitat Management Plan 32127-54-00075 & 32127-54-00076 231 E Kilmarnock Rd Shelton, WA 98584 Overview This report details a Habitat Management Plan (HMP) for the above referenced properties in Mason County, Washington. The purpose of this report is to address any potential adverse impacts from the construction of a Single-Family Residence (SFR) on each lot within the buffer of a Type-F stream. The Mason County Resource Ordinance (MCRO) requires a 150ft buffer with an additional 15ft building setback for Type-F streams. (see figure 1). However, the Resource Ordinance allows for a reduction in the buffer/setback if the lot was legally established prior to the effective date of the Resource Ordinance if it is the minimum necessary to allow reasonable use of the property. This report proposes a reduction in the stream buffer to 110ft with an additional 15ft structure setback. The SFRs are proposed approximately ±125-130ft from the ordinary high- water mark of the Type-F stream. Mitigation measures have been designed to offset the potential impacts of these activities on the ecological functions of the stream buffer. Mitigation measures include construction BMPs and re- establishing a portion of the stream buffer with native plantings within a combined mitigation area for both lots. The objectives of this report are as follows: • Identify potential impacts of the construction of the proposed structure within the stream buffer, on the buffer's ecological functions and fish and wildlife habitat. • Determine mitigation measures that would offset those impacts and result in a "no net loss" to ecological functions and fish and wildlife habitat within the remaining buffer. 1 Project: 2021-HMP-008 May 2021 A RCTOSAERIAL e -Mason County WAGIS 13 Ew HERE:.•,-.-F+.0 nOc>_SF»E Figure 1:Vicinity map of project. Property Description & Project Background The parcels are a combined 0.67 acres in size and located in the SE% of the SE% of section 27, Township 21 North, Range 3 West. The building sites are already cleared of vegetation from past management up to ±120ft of the stream. The SFRs are proposed at ±125-130ft from the stream. The Mason County Resource Ordinance requires a 150ft buffer with an additional 15ft structure setback, which encompasses the entire subject property. This report proposes a reduction of the regulated buffer to 100ft with an additional 15ft structure setback. This buffer reduction is the minimum necessary to afford the property owner with a reasonable use of the lot. The proposed buffer reduction is also compatible with the character of surrounding permitted uses and would not adversely affect traffic circulation. 2 Project: 2021-HMP-008 May 2021 ARCTOSAEpIAL ?. R s 9 fA• Figure 2:Map showing Hood Canal,the regulated 100'buffer as the solid yellow line and the 115'structure setback as the dashed yellow line. The red polygon is the parcel in question. Analysis of Potential Impacts Vegetated buffers serve an important role in protecting critical public resources, as well as fish and wildlife habitat from adverse impacts associated with development. Below are the potential adverse impacts to ecological function associated with the construction of this proposed structure within the shoreline buffer. - Increased storm-water runoff and erosion Impervious surfaces such as roofs and driveways contribute to increased flow of runoff during storm events. This increased flow could contribute to erosion and increased sediment reaching the stream without a proper storm water management plan. The proposed building sites are already cleared and construction BMPs have been proposed in the "Mitigation 3 A RCTOS Project: 2021-HMP-008 May 2021 AERIAL Measures" section of this report below. No increase in storm-water runoff is anticipated. - Stream bank de-stabilization Removal of buffer vegetation and increasing storm water run-off can speed erosion of streambanks and make them unstable. No vegetation removal is proposed, and no increased risk of erosion is anticipated. - Loss of wildlife habitat The combined development footprint of these structures within the buffer is ±1,200ft2. No native vegetation will be removed in the construction process since the project sites are already devoid of vegetation. Mitigation measures, including native plantings, will increase the amount of wildlife habitat adjacent to the building site and have a net ecological benefit to the stream buffer. - Increased disturbance from noise pollution A temporary increase in noise from construction activities is likely to occur. but activities will be limited to daylight hours, and the projects are located in an area along the stream where human noises are a common occurrence. Also, no known nesting sites or individual occurrences of priority habitats and species have been identified near the project sites. - Increased Solar input The proposed structure is sited in an area with mature conifers that will be left to shade the s g stream and no native vegetation will be removed in the process of construction. The structure itself and native plantings within the mitigation area will benefit the stream b increasing shade and reducing g Y g g solar input. III Mitigation Measures To avoid, minimize, and mitigate for the potential adverse impacts identified above, the following have been identified as appropriate measures for this project: 4 Project: 2021-HMP-008 May 2021 A RCTOSAERIAL - Minimizing/avoiding impact The proposed projects minimize the impact to the stream buffer by limiting the square footage of the structures within the buffer to ±1,200ft2 and placing them as far from the stream as feasible. The structures will be constructed in an area already devoid of vegetation. - Best Management Practices for construction Construction activities related to this project will be restricted to favorable weather conditions and best management practices for reducing disturbance and erosion will be followed, including placing straw over exposed areas, and erecting silt fencing below the project area. Equipment will be checked daily for leaks and all fuel, lubricant, and chemicals will be stored outside the shoreline buffer. - Clustering of development All activities related to these projects will be clustered to the extent possible without impacting more of the shoreline buffer than necessary. Equipment and materials will be parked/stored outside the stream buffer whenever possible. - Removal of invasive species All occurrences of noxious weed species observed in the vicinity of the project site and mitigation area will be mechanically removed without the use of chemical herbicides. - Stream buffer re-vegetation A total mitigation area of 600ft'will be restored with native shoreline vegetation through plantings per the planting guidelines described below. The mitigation area to be replanted is an area between the proposed structures, along the lot line between the two properties. The minimum number of trees, shrubs, and ferns/groundcovers to be planted in order to meet the required densities are as follows: 5 Project: 2021-HMP-008 May 2021 A RCTOSAERIAL -Trees = 6 (can be zero if an additional 18 shrubs are added) -Shrubs = 24 -Ferns/groundcovers = 37 Once the mitigation area is established, the lot owners must allow the planted vegetation to grow to the full mature size of the species selected, without pruning or trimming. The mitigation area must also be treated as if part of the regulated stream buffer indefinitely. Also, any additional landscaping within the lot area is encouraged to consist of native plant species typically found in undisturbed riparian areas. Species selected should include common riparian vegetation not currently on the property which will result in a net increase in species richness and biodiversity within the buffer. Planting Guidelines for the Mitigation Area (adapted from Appendix C of the Mason County Resource Ordinance) Earthwork Machinery earthwork will be restricted to the minimum necessary in order to implement this plan; planting holes for specified vegetation installation will be hand dug. Native Plantings Native plantings will be installed within the mitigation area parallel to the edge of the buffer to achieve the following minimum densities: Trees — 10' on center Shrubs — 5' on center Ferns, grasses, and ground-covers — 4' on center The plan calls for installing single trees, or clusters of three shrubs, on 10ft centers and single shrubs on 5ft centers. Areas between will be filled in with ferns, grasses, or ground-covers on 4ft centers. The entire mitigation area should be mulched to prevent any non-native species from establishing within the 6 A RCTOS Project: 2021-HMP-008 May 2021 ALRI A L mitigation area. Exact placement of installed materials will be up to the landscape installer, following the basic 10-foot spacing pattern described above and using the planting map as a guide. Successful implementation of the planting plan will achieve a structurally and biologically diverse plant community that mimics undisturbed shoreline buffers. Volunteer native vegetation can be counted towards the target densities of restoration area at the time of monitoring audits. Native plant species appropriate for this area include, but are not limited to the following: Trees: Pacific madrone (Arbutus menziesii) Western red cedar (Thuja plicata) Douglas fir (Pseudotsuga menziesii) Garry oak (Quercus garryana) Western hemlock (Tsuga heterophyllo) Grand fir (Abies grandis) Cascara (Rhamnus purshiona) Cottonwood (Populus balsamifera) Shore pine (Pinus contorta v. contorta) Pacific crabapple (Malus fusca) Serviceberry (Almenlanchier alnifolia) Shrubs: Ocean spray (Holodiscus discolor) Wax myrtle (Myrica californica) Thimbleberry (Rubus parviflorus) Hookers willow (Salix h000keriana) Tall Oregon grape (Mahonia aquifolium) Nootka rose (Rosa nutkana) Salmonberry (Rubus spectabilis) Salal (Gaultheria shallon) Evergreen huckleberry (Vaccinium ovatum) Snowberry (Symphorocarpus albus) Elderberry (Sambucus racemosa) Red osier dogwood (Cornus stolonifera) Project: 2021-H M P-008 May 2021 ARGTOSAERIAL Ferns, grasses, and ground-covers: Sword fern (Polystichum munitum) Bracken fern (Pteridium aquilinum) Tufted hairgrass (Deschampsia cespitosa) Coastal strawberry (Fragaria chiloensis) Seashore saltgrass (Distichlis spicata) Coastal lupine (Lupinus littoralis) Silverweed (Potentilla pocifica) Twinberry (Lonicera involucrate) Henderson's checker-mallow (Sidalcea herdersonii) All planting should occur during winter dormancy. The optimum time for planting is from February to March. Installation Installation of the prescribed vegetation will be performed by qualified landscapers familiar with planting of native vegetation in natural settings. Installation will be performed only after construction on the property is completed to avoid damage to the plantings. Fertilizing Due to the proximity of the mitigation area to the Hood Canal, NO fertilizer will be used during plant installation or maintenance. Maintenance Maintenance of the installations will be the responsibility of the landscape installer. Maintenance is to include any weeding or watering necessary to ensure plant survival for up to three years after the date of installation. 8 Project:2021-HMP-008 May 2021 ARMSA E R I A L _ •�. ' Regulated 1 SOft ARCTOS f Stream Buffer T � AERIAL 4 �y Regulated 165ft •• Structure Environmental Consulting I Drone Imagery Setback pp Box2466 Shelton,WA 98584 (425)344-9315 `=�' ' •'a Proposed 110ft arctosaerialCa)gmail.com Stream Buffer www.arctosaerial.com d Type-F Stream . A * °,t �Af► Proposed 125ft Structure ' " Setback i> �e ►� -a 131 o � � co 0 o o v Ln co � o O rn r` 4 `o ff Mitigation Area s N c (600ft') r� ;V > �rV N X O N liJ � M N Vl ? Map created by: Rob Nagel May 5th, 2021 `K. Proposed SFRs Revison: . ', � t• N 4 , * • 0 20 40 60 80 ft Scale: 1" = 30' 10 A RCTOS Project: 2021-HMP-008 May 2021 AERIAL Monitoring Following the implementation of the mitigation measures, an annual report will be submitted to the county for 3 years post construction. The report will detail the presence of new, or the reoccurrence of any invasive species. Invasive species found on site will again be removed mechanically, using hand tools only to reduce disturbance to the shoreline buffer. The annual report will also document the planting success of the mitigation area. If planting survival in the mitigation area falls below 90% in the first three years after installation. The area will be re- planted to meet the target densities. If any failures of mitigation measures are identified during the annual inspection, corrective actions will be recommended in the report and will be taken by the property owner to restore them to working order as soon as possible. Summary This report Identifies potential impacts of the construction of two proposed SFRs, with a combined square footage of ±1,200ft2 footprint within a regulated Type-F stream buffer. The proposed building sites are currently devoid of vegetation and provide little benefit to the stream and its buffer. Mitigation measures have been proposed to avoid, minimize, and mitigate for those impacts identified on the stream buffer's ecological functions and fish and wildlife habitat. Successful implementation of the proposed mitigation measures will result in a net benefit to the stream and its buffer's ecological functions, structural diversity, and species richness. Mitigation measures include construction BMPs and re-establishing native vegetation in a 600ft2 mitigation area for a mitigation ratio of 1:112. 11 Project:2020-HMP-205 December 2020 ARMS References Environmental Laboratory. (1987). "Corps of Engineers Wetlands Delineation Manual,"Technical Report Y-87-1, U.S.Army Engineer Waterways Experiment Station,Vicksburg, Miss. Guard,J. (1995). Wetland Plants of Oregon &Washington. Lone Pine Publishing.240 pp. Edmonton, Alberta, Canada. Hruby,T. (2014).Washington State Wetland Rating System for Western Washington: 2014 Update. (Publication#14-06-029). Olympia, WA: Washington Department of Ecology. Munsell Color(Firm). (2009). Munsell soil color charts:with genuine Munsell color chips. Grand Rapids, MI Pojar,J. and A. MacKinnon. 1994. Plants of the Pacific Northwest Coast (Revised Edition 2014). Lone Pine Publishing. 528 pp.Vancouver, British Columbia,Canada. United States Department of Agriculture, Natural Resources Conservation Service. 2010. Field Indicators of Hydric Soils in the United States,Version 7.0. L.M.Vasilas, G.W. Hurt,and C.V. Noble(eds.). USDA, NRCS, in cooperation with the National Technical Committee for Hydric Soils. U.S.Army Corps of Engineers 2018. National Wetland Plant List,version 3.4, http://wetland- plants.usace.army.mil/U.S.Army Corps of Engineers, Engineer Research and Development Center Cold Regions Research and Engineering Laboratory, Hanover, NH U.S.Army Corps of Engineers. 2010. Regional Supplement to the Corps of Engineers Wetland Delineation Manual:Western Mountains,Valleys, and Coast Region (Version 2.0),ed.J. S. Wakeley, R.W. Lichvar,and C.V. Noble. ERDC/EL TR-10-3.Vicksburg, MS: U.S.Army Engineer Research and Development Center. I 13 UIZ15`i00b7ei ,!]� Jr FT_ i tt �U ij er -A---- — - , - -1-+F-E -t- --i I -�� r- rI- _s_---t-_' �-^— -�-}- --i----i- ----�•-•-t-- —�-_-a-_�_.!---�-i---i" d--i-_-1_--t_ ...J. .n___ -r I _ e I ' __nn i ' 4 t I , �._ it -I I it - -�-I I- 1 f ` -1-�- { . , 14 1 1# • I l i E�-- - • 1