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HomeMy WebLinkAboutLUA-08-081_MiscDenis Law Mayor February 15, 2010 Kathi Bresler Department of Community and Economic Development Alex Pietsch, Administrator Church Development Consultants 3623 -324 th Avenue SE Fall City, WA 98024 SUBJECT: New Life Church . LUA08-081, ECF, SA-A Approval of Final Stream Mitigation and Monitoring Plan Dear Ms. Bresler: Barghausen and Sewall Wetland Consulting, Inc. have submitted the Final Stream Buffer Mitigation Plan for the street frontage improvements required for the. subject project. At this time, the Final Mitigation and Maintenance and Monitoring proposalhas been approved by the City of Renton. Please find enclosed your stamped copy of the approved plans .. You may commence installation of the proposed mitigation. After installation of the mitigation, please have your contracted biologist submit a letter verifying that the mitigation installation complies with the approved Final Stream Buffer Mitigation Plan. If any portion Of the installed mitigation is different then the approved plan, please have your biolo'gist submit an "as built" plan set with the compliance letter anda biological justification for the changes to the approved plan. Once'the mitigation installation has been verified as consistent with the approved . mitigation plan by the project biologist and City project manager, your minimum 5-year maintenance and monitoring period will begin. The City will provide the applicant with ,a letter identifying the required submittal date for. the first monitoring report. Additionally, a surety device is required for the structures, improvements,and stream mitigation. Based on the contract (attached) I received for maintenance and monitoring' for the. New Life Church, street frontage improvements, stream mitigation project, ·the total amount of your surety device is $16,125.00. The specific breakdown is as follows: " Renton City Hall • 1055 South Grady Way • Renton, Washington 98057, • _ rentonwa.gov • Construction Monitoring Maintenance Monitoring TOTAL @125% $1,500 $3,600 $7,800 $12,900 $16,125 Approval of Final SIre New Life Churen onitaring and Mitigation Plan Page 201 2 . This amount is deemed sufficientto guarantee that structures, improvements, and mitigation required by permit condition will perform satisfactorily for a minimum of five (5) years after they have been completed. Please come to the 6th Floor of Renton City Hall to pay the surety device. Thank you for your diligent work in protecting Renton's critical areas. Once I have received a receipt for the surety devite, we will issue the construction permit for the street frontage improvements. If you have any questions please feel free to contact me at (425) 430-7314. Sincerely, u1/' ... ,/l!l / .. . !lah~UJ!&~ Vanessa Dolbee Senior Planner Encl: . Approved Finai Stream Mitigation and Monitoring_ Plan, Mitigation ,and Monitoring Cost Estimates ee: .New Life Church / Owner!s) . Ivana Halversen~ Contact Jan lilian, Plan Re:viewer , LuAOS-OS! NEW LIFE CHURCH SR-169 FRONTAGE IMPROVEMENTS & STREAM BUFFER MITIGATION NOTES AND SPECIFICATIONS February 11, 2010 1.0 MITIGATION CONCEPT AND GOALS 1.1 MITIGATION CONCEPT The proposed project is the expansion of SR 169 per the City's requirements. For expansion of the highway, the project will enhance the opposite adjacent buffer of Madsen Creek with native tree and shrub plantings. In .addition, habitat features will be installed along the stream to provide greater ecological benefit. The mitigation area will be monitored five times over a five-year period as required by the City. 1.2.0 MITIGATION GOALS 1.2.1 Enhance 39,363sf of stream buffer through non-native invasive vegetation removal and replanting with native plantings and habitat features. 2.0 CONSTRUCTION SEQUENCE The construction sequence of this project will be implemented as follows: 2.1 Pre-construction meeting 2.2 Plant material installation 2.3 Construction inspection 2.4 Agency approval 2.5 Monitoring inspection and reporti ng 2.6 Project completion 2.1 Pre-construction Meeting A pre-construction meeting will be held on-site prior to commencement of construction, to inclu e the Owner's biologist, the contractor, the Owner and the WDFW Biologist and the City Biologist. The approved plans and specifications will be reviewed to ensure that all parties involved understand the intent of the construction documents, specifications, site environmental constraints, sequences, and inspection requirements. 2.2 Plant Material Installation All weedy non-native material including Himalayan blackberry will be removed by hand from the enhancement areas. All plant material will be planted by hand per detail and Construction and Planting Notes. The Mitigation Plan specifies the required size, species, quantity, and location of plant materials to be installed. The contractor will re-seed or over-seed all hydroseeded areas disturbed during the planting process. Plant substitutions or modifications to locations shall be approved in writing, by the Owner's biologist prior to installation. 2.3 Construction Inspection Upon completion of installation, the Owner's biologist will conduct an inspection to confirm proper implementation of the Mitigation Plan. Any corrections, substitutions or missing items will be identified in a "punch list". Items of particular importance will be soils in pits, pit size, plant species, plant size, mulch around pits, and tree staking. Upon completion of planting, if installation or materials vary significantly from the Mitigation Plan, the contractor will submit a reproducible "as-built" drawing to the Owner. 2.4 Agency Approval Following acceptance of the installation by the Owner's biologist, a letter will be prepared to the City Biologist requesting approval of the installation. 2.5 Monitoring Inspection and Reporting The monitoring program will begin in the first growing season (approximately one year) following installation approval by the City Biologist. The subsequent monitoring inspections will be conducted in accordance with the approved Monitoring Program. 2.6 Project Completion If, after the final year of monitoring, the project has satisfied the objectives and goals of the approved Mitigation Plan, the Owner's biologist will prepare a letter to the City requesting final approval & closure of the mitigation plan. 3.1 SITE PREPARATION 3.1.1 The Landscape Contractor will hand grub all blackberry varieties and English ivy (if any) as specified in Section 4.13 of the plan. Weed debris will be disposed of off site. 3.2 PLANT AND HABITAT MATERIALS 3.2.1 All plant materials will be as specified in the plant schedule. Only vigorous plants free of defects, diseases and infestation are acceptable for installation. 3.2.2 All plant materials will conform to the standards and size requirements of ANSI Z60.1 "American Standard for Nursery Stock". All plant materials will be native to the Puget Sound Region. Plant materials will be propagated from native stock; no cultivars or horticultural varieties will be allowed. All plant materials will be grown from nursery stock unless otherwise approved. 3.2.3 All nursery grown plant materials will be in containers or balled and burlapped. Bare root plantings will be subject to approval. 3.2.4 All plant materials stored on-site longer than two (2) weeks will be organized in rows and maintained by the contractor at no additional cost to the owner. Plant materials temporarily stored will be subject to inspection and approval prior to installation. 3.2.5 Substitution requests must be submitted in writing to the Owner and approved by the Owner's biologist in writing prior to delivery to site. 3.2.6 All plant materials will be dug, packed, transported and handled with care to ensure protection from injury. All plant materials to be stored on site more than 24 hours will be heeled into topsoil or sawdust. Precautionary measures shall be taken to ensure plant materials do not dry out before planting. Plants will be shaded and saturated until time of installation. Immediately after installation the mitigation planting area will be saturated to avoid capillary stress. 3.2.7 The contractor will verify all plant materials, the quantities shown on the planting plan, and the plant schedule. The quantity of plant materials shown on the plan takes precedent over the quantity on the plant list. - 2 - 3.3 PLANT MATERIAL INSTALLATION 3.3.1 All planl and habitat materials must be inspected prior to installation to verify conformance of the materials with the plant schedule including size, quality and quantity. Any plant or habitat materials deemed unsatisfactory will be rejected. 3.3.2 All plant materials delivered and accepted should be planted immediately, following installation of the habitat features depicted on the plan. Plant materials not planted within 24 hours will be heeled-in per note 3.3.3 All planting pits will be circular with vertical sides, and will be sized per detail on the mitigation plan and filled with pit soils approved by the Owner's biologist. If native soils are determined to be unacceptable by the Owner's biologist, pit soils will be amended with Cedar Grove mulch or equivalent. 3.3.4 No fertilizers will be used within the mitigation area. In buffer areas only, install "Agriform", or equal plant fertilizer to all planting pits as specified by manufacturer. Fertilizers are allowed only below grade in the planting pits in the buffer areas. No sewage sludge fertilizer ("SteerCo" or "Growco") is allowed in the mitigation area. 3.3.5 All containerized plant materials will be removed from their containers carefully to prevent damage to the plant and its roots. Plants removed from their containers will be planted immediately. 3.3.6 All plant materials will be placed as shown on the approved mitigation plan. If the final installation varies from the approved mitigation plan, the contractor will provide a reproducible mylar as-built of the installed conditions. All plant material will be flagged by the contractor. 3.3.7 All conifer trees will be staked per the detail on the mitigation plan. All deciduous trees 1" caliper and larger will be staked per the detail on the mitigation plan. Remove tree staking and guy wires from all trees after one year. Cut guy wires away from trees and remove wire and tree stakes from site. 3.4 PLANTING SCHEDULE AND WARRANTY 3.4.1 A fall-winter installation schedule (October 1st -March 15th) is preferred for lower mortality rates of new plantings. If plant installation occurs during the spring or summer (March 15th -Oct. 1st) the plantings will be irrigated by hand, with water from a watering truck, for 15 minutes every day until fall rains can provide adequate moisture to support plant materials. 3.4.2 The installer will warrant all plant materials to remain healthy and alive for a period of one year after final acceptance. The installer will replace all dead or unhealthy plant materials per the approved plans and specifications. 3.5 SITE CONDITIONS 3.5.1 The installer will coordinate with the Owner and the Owner's biologist for construction scheduling. 3.5.2 All plant material will be planted with suitable soils per planting details. Soils from planting holes will be spread and smoothed across the mitigation area. -3- 4.0 MAINTENANCE PROGRAM INTRODUCTION This maintenance program outlines the program. procedures and goals for maintenance at the mitigation site. This maintenance program will be the responsibility of the project owner through the duration of its ownership of the mitigation area. or throughout the duration of the monitoring period, whichever is longer. The maintenance contractor will complete the work as outlined below. 4.1 MAINTENANCE WORK SCOPE 4.1.1 The primary goals of the mitigation plan are to enhance the stream buffer areas. To accomplish this goal, normal landscaping methods must be modified to include: a. No mowing or trimming of ground cover or vegetation in the mitigaUon area except for control of reed canary grass and other tall growing grasses in and around plantings. Reed canary grass as well as other tall grasses such as fescue, quack grass etc. shall be cut away from base of installed plant to avoid overgrowth of the native planting. Alternatively, a water permeable fabric or cardboard disk 12"-18" in diameter may be placed around base of plant to block tall grass growth from competing with planting. b. No placement of fertilizers in the mitigation area. c. No placement of bark mulch or equivalent in the mitigation area, except as noted in the planting details. d. No placement of grass clippings. landscape debris, fill or ornamental plant materials in the mitigation area. 4.1.2 Work to be included in each site visit: a. Remove alilitler including paper, plastic, bottles, construction debris, yard debris, etc. b. Remove all blackberry varieties and scotch broom within the mitigation area. All debris is to be removed from site and disposed in an approved landfill. c. Repair silt andlor permanent fencing and signage as needed. 4.1.3 Work to be completed on an annual basis includes: a. Areas containing Himalayan blackberry should be controlled by hand cutting the blackberry and treating the remaining cut stems only with a glyphosphate herbicide such as Roundup or Rodeo. b. Replace dead or failed plant materials. Replacement plantings are to be of same species, size and location as original plantings. Plantings are to be installed during the dormant period. 4.2 MAINTENANCE SCHEDULE The Owner will conduct all items listed in the Maintenance Work Scope on an annual basis. Additional work may be required per the Monitoring Report and as approved by the City Biologist. Additional work may include removal of the grasses around each shrub and tree, installation of -4- wood chips at each shrub and tree base, reseeding the mitigation area, re-staking existing trees and erosion control protection. 4.3 WATERING REQUIREMENTS 4.3.1 If plantings are installed within the dormant period throughout the winter months (October through March 15th) watering is not required. 4.3.2 If plantings are installed during the summer months (March through October 1 st ) a temporary irrigation system will be required. The temporary irrigation system may be removed after the first year providing the plantings are established and acclimated to on-site conditions per Construction and Plantings Notes Sec. 4.0. 4.3.3 Irrigation will continue from initiation through October 1 st , or between June 1 st and Oct. 1st for any subsequent year. Irrigation, if required, will provide head to head coverage for 15 minutes per day every day. 4.4 CLOSEOUT OF FIVE YEAR MONITORING PROGRAM Upon completion of the monitoring program and acceptance of the buffer mitigation by the City Biologist, the maintenance of the project will be reduced to include removal of litter and debris, repair of perimeter fencing and signage, removal of noxious weeds and undesirable vegetation, and repair of vandalized areas. 5.0 MITIGATION MONITORING PROGRAM 5.1 SAMPLING METHODOLOGY The enhanced buffer will be monitored five times over a five year period. Monitoring will be conducted using the techniques and procedures described below to quantify the survival, relative health and growth of plant material. A monitoring report submitted following each monitoring visit will describe and quantify the status of the mitigation at that time. 5.1.1 Vegetation The vegetation monitoring consists of inspection of the planted material to determine the health and vigor of the installation. All the planted material in the buffer will be inspected during each monitoring visit to determine the level of survival of the installation. 5.2 STANDARDS OF SUCCESS 1. Evaluation of the success of the mitigation project will be based upon an 100% survival at the end of Year 1 and 80% survival of all planted woody vegetation at the end of year 5. 2. Volunteer native, non-invasive species will be included as acceptable components of the mitigation. 3. Not more than 10% non-native invasive species within the mitigation area. -5- 5.3 CONTINGENCY PLAN A contingency plan can be implemented if necessary. Contingency plans can include re-grading, additional plant installation, erosion control, additional water quality facilities, plant substitutions including type, size, and location. If the monitoring results indicate that any of the performance standards are not being met, it may be necessary to implement all or part of the contingency plan. Careful attention to maintenance is essential in ensuring that problems do not arise. Should any of the site fail to meet the success criteria, a contingency plan will be developed and implemented with the City approval. Such plans are prepared on a case-by-case basis to reflect the failed mitigation characteristics. Contingency/maintenance activities will include, but are not limited to: • Replacing all plants lost to vandalism, drought, or disease, as necessary. • Replacing any plant species with a 20 percent or greater mortality rate with the same species or similar species approved by the City Biologist. • Irrigating the enhancement area only as necessary during dry weather if plants appear to be too dry, with a minimal quantity of water. • Removing all trash or undesirable debris from the buffer areas as necessary per 4.0 Maintenance Program. -6- {jJAo8-OBI Sewall Wetland Consulting, Inc. SR-169 FRONTAGE IMPROVEMENTS MITIGATION AND MONITORING COST ESTIMATES NEW LIFE CHURCH February 11, 2010 1 Construction Monitoring: The final mitigation ptan approved by City of Renton wit! require a o,ologist to visit the site during construction to monitor mitigation activities, including placement and planting of specified vegetation and mitigation measures. Once the mitigation 8re8 has been planted and amended per the approved Mitigation Plan, a biologist will visit the site to approve and accept the final planting and confirm special requirements for the landscape contractors required maintenance period. Fee: $1,500 2. Baseline Monitoring Report (First Year Monitoring): Within one month after the mitigation project has been planted and vegetation is established, an as·builUbaseline monitoring report will be provided to City of Renton. This report must (a) document the mitigation construction and any deviations from the approved mitigation plan, (b) establish and identify baseline conditions in permanently marked vegetation monitoring plots, transects, and photo stations, and (c) describe monitoring methodologies. Fee: $1,800 3. Long-Term Mitigation Monitoring: Mitigation projects must be monitored semi-annually each growing season (early spring and late fall) for five (5) years. The estimated cost for each year of monitoring is $1,500, for the four (4) years after the first year. Fee: $6,000 4. Long Term Maintenance: Maintenance and replacement of any damaged plants/materials in the mitigation area should be replaced annually as needed. The estimated cost for each year of maintenance is $800 per year for 4 years (no maintenance is anticipated for the first year). Fee: $3,600 Denis Law Mayor ~ March 24, 2010 Kathi Bresler Church Development Consultants 3623 -324th Avenue SE Fall City, WA 98024 RE: New life Church LUA08-081, ECF, SA-A • • . ~. Ec()nolmic Development Alex Pietsch, Administrator Approval of Final Stream & Wetland Mitigation and Monitoring Plan Dear Ms. Bresler: Barghausen and Sewall Wetland Consulting,. Inc. have submitted the Final New Life . Church -Phase 1 Wetland and Stream analysis and Mitigation Report along with the Wetland Buffer Mitigation Plan for the required fire lane connection along the west side of the auditorium. In a letter dated, February 15, 2010, the City approved a Final Mitigation and Maintenance and Monitoring proposal for Madsen Creek stream buffer mitigation. At this time, the Final Wetland Mitigation and Maintenance and Monitoring proposal has been approved by the City of Renton, subject to the following condition: The applicant shall install a split rail fence and critital area signage, perRMC 4-3-OS0E.4.e Fencing, to protect the critical areas from potential· future environmental. degradation. Pie ase find enclosed your stamped copy of the approved plans .. You may commence installation of the proposed mitigation. After installation of the mitigation, please have· your" contracted biologist submit a letter verifying that tflE! mitigation installation complies with the approved Final Wetland Buffer Mitigation Plan. ·If any portion of the installed mitigation is differentthen the approved plan, please have your biologist submit .an "as built" plan set with the compliance letter and a biological justification for the changes to the approved plan. Once the mitigation installation has been verified as consistent with the. approved mitigation plan by the project biologist and City project rnanager, your minimum 5-year maintenance and monitoring period will begin .. The City will provide the applicant with ~ letter identifying the required submittal date for the first monitoring report; Additionally, a surety device is required for the structures, improvements, arid stream and wetland rnitigati.on. . Renton City Hall • .1055 South Grady Way • Renton, Washington 98057 .• rentonwa.gov . Ms. Kathi Bresler • Page 2 of2 March 24. 2010 Based on discussions. with Barghausen, the applicant has identified their' interest to combine the Stream and Wetland Mitigation Maintenance .and Monitoring. The . combination of these two mitigation projects would simplify the reporting to the City over the next S years. As such, the applicant submitted,anew contract (attached) that estimates costs for both mitigation projects. Based on the contact we received for maintenance and monitoring for the New Life Church,street frontage improvements' and fire larieconnection,wetland and stream mitigation project, the total amount of your surety device is $27,500.00. The speCific breakdown is as follows: · Construction Monitoring .Maintenance Monitoring' TOTAL @125% $1;900 $3,600 $16.S00. $2i,000 $27,500 This amount is deemed sufficient to guarantee that structures, improvements, and mitigation required by permit condition will perform satisfactorily for a minimum of five (S)years after they have. been completed. Please come to .the 6th Floor of Renton City Hall to pay the surety device. Thank you for your diligent work in protecting Renton's critical areas. Once I have · received a receipt for the surety device, we will issue the construction permit for the · street frontage improvements. If you have any questions please feel free to contact me at (42S) 430-7314. Sincerely, c/t4/~cliJJ~ . Vanessa Dolbee .' Senior Planner End: Approved Final Wetland Mitigation and Monitoring Plan, Wetland & Stream Mitigation and Monitoring Cost Estimates cc: New Life Church I Owner(s) Ivana Halversen, Contact Jan lilian/ Plan Reviewer 1.0 MITIGATION CONCEPT AND GOALS 1.1 MITIGATION CONCEPT The proposed project is the construction of the fire lane per the City's requirements. For development of the fire lane portion of the overall project. The project will enhance the adjacent wetland buffer with native tree and shrub plantings. The mitigation area will be monitored eight times over a five-year period as required by the City. 1.2.0 MITIGATION GOALS 1.2.1 Enhance 2,206 sf of buffer through non-native invasive vegetation removal and replanting with native plantings 1.2.2 Provide 1,973sf buffer addition for impacts to 1,909sf buffer subtraction in a protected easement. 2.0 CONSTRUCTION SEQUENCE The construction sequence of this project will be implemented as follows: 2.1 Pre-construction meeting 2.2 Plant material installation 2.3 Construction inspection 2.4 Agency approval 2.5 Monitoring inspection and reporting 2.6 Project completion 2.1 Pre-construction Meeting A pre-construction meeting will be held on-site prior to commencement of construction, to include the Owner's biologist, the contractor, the Owner and the WDFW Biologist and the City Biologist. The approved plans and speCifications will be reviewed to ensure that all parties involved understand the intent of the construction documents, specifications, site environmental constraints, sequences, and inspection requirements. 2.2 Plant Material Installation All weedy non-native material including Himalayan blackberry will be removed by hand from the enhancement areas. All plant material will be planted by hand per detail and Construction and Planting Notes. The Mitigation Plan specifies the required size, species, quantity, and location of plant materials to be installed. The contractor will re-seed or over-seed all hydroseeded areas disturbed during the planting process. Plant substitutions or modifications to locations shall be approved in writing, by the Owner's biologist prior to installation. 2.3 Construction Inspection Upon completion of installation, the Owner's biologist will conduct an inspection to confirm proper implementation of the Mitigation Plan. Any corrections, substitutions or miSSing items will be identified in a "punch list". Items of particular importance will be soils in pits, pit size, plant species, plant size, mulch around pits. and tree staking. Upon completion of planting, if installation or materials vary significantly from the Mitigation Plan, the contractor will submit a reproducible "as-built" drawing to the Owner. 2.4 Agency Approval Following acceptance of the installation by the Owner's biologist, a letter will be prepared to the City Biologist requesting approval of the installation. 2.5 Monitoring Inspection and Reporting The monitoring program will begin in the first growing season (approximately one year) following installation approval by the City Biologist. The subsequent monitoring inspections will be conducted in accordance with the approved Monitoring Program. 2.6 Project Completion If, after the final year of monitoring, the project has satisfied the objectives and goals of the approved Mitigation Plan, the Owner's biologist will prepare a letter to the City requesting final approval & closure of the mitigation plan. 3.1 SITE PREPARATION 3.1.1 The Landscape Contractor will hand grub all blackberry varieties and English ivy (if any) as specified in Section 4.13 of the plan. Weed debris will be disposed of off site. 3.2 PLANT AND HABITAT MATERIALS 3.2.1 All plant materials will be as specified in the plant schedule. Only vigorous plants free of defects, diseases and infestation are acceptable for installation. 3.2.2 All plant materials will conform to the standards and size requirements of ANSI Z60.1 "American Standard for Nursery Stock". All plant materials will be native to the Puget Sound Region. Plant materials will be propagated from native stock; no cultivars or horticultural varieties will be allowed. All plant materials will be grown from nursery stock unless otherwise approved. 3.2.3 All nursery grown plant materials will be in containers or balled and burlapped. Bare root plantings will be subject to approval. 3.2.4 All plant materials stored on-site longer than two (2) weeks will be organized in rows and maintained by the contractor at no additional cost to the owner. Plant materials temporarily stored will be subject to inspection and approval prior to installation. 3.2.5 Substitution requests must be submitted in writing to the Owner and approved by the Owner's biologist in writing prior to delivery to site. 3.2.6 All plant materials will be dug. packed, transported and handled with care to ensure protection from injury. All plant materials to be stored on site more than 24 hours will be heeled into topsoil or sawdust. Precautionary measures shall be taken to ensure plant materials do not dry out before planting. Plants will be shaded and saturated until time of installation. Immediately after installation the mitigation planting area will be saturated to avoid capillary stress. 3.2.7 The contractor will verify all plant materials, the quantities shown on the planting plan, and the plant schedule. The quantity of plant materials shown on the plan takes precedent over the quantity on the plant list. 3.3 PLANT MATERIAL INSTALLATION 3.3.1 All plant and habitat materials must be inspected prior to installation to verify conformance of the materials with the plant schedule including size, quality and quantity. Any plant or habitat materials deemed unsatisfactory will be rejected. 3.3.2 All plant materials delivered and accepted should be planted immediately, following installation of the habitat features depicted on the plan. Plant materials not planted within 24 hours will be heeled-in per note 3.3.3 All planting pits will be circular with vertical sides, and will be sized per detail on the mitigation plan and filled with pit soils approved by the Owner's biologist. If native soils are detenmined to be unacceptable by the Owner's biologist, pit soils will be amended with Cedar Grove mulch or equivalent. 3.3.4 No fertilizers will be used within the mitigation area. In buffer areas only, install "Agriform", or equal plant fertilizer to all planting pits as specified by manufacturer. Fertilizers are allowed only below grade in the planting pits in the buffer areas. No sewage sludge fertilizer ("SteerCo" or "Growco") is allowed in the mitigation area. 3.3.5 All containerized plant materials will be removed from their containers carefully to prevent damage to the plant and its roots. Plants removed from their containers will be planted immediately. 3.3.6 All plant materials will be placed as shown on the approved mitigation plan. If the final installation varies from the approved mitigation plan, the contractor will provide a reproducible mylar as-built of the installed conditions. All plant material will be flagged by the contractor. 3.3.7 All conifer trees will be staked per the detail on the mitigation plan. All deciduous trees 1" caliper and larger will be staked per the detail on the mitigation plan. Remove tree staking and guy wires from all trees after one year. Cut guy wires away from trees and remove wire and tree stakes from site. 3.4 PLANTING SCHEDULE AND WARRANTY 3.4.1 A fall-winter installation schedule (October 1st -March 15th) is preferred for lower mortality rates of new plantings. If plant installation occurs during the spring or summer (March 15th -Oct. 1 st ) the plantings will be irrigated by hand, with water from a watering tnuck, for 15 minutes every day until fall rains can provide adequate moisture to support plant materials. 3.4.2 The installer will warrant all plant materials to remain healthy and alive for a period of one year after final acceptance. The installer will replace all dead or unhealthy plant materials per the approved plans and specifications. 3.5 SITE CONDITIONS 3.5.1 The installer will coordinate with the Owner and the Owner's biologist for construction scheduling. 3.5.2 All plant material will be planted with suitable soils per planting details. Soils from planting holes will be spread and smoothed across the mitigation area. 4.0 MAINTENANCE PROGRAM INTRODUCTION This maintenance program outlines the program, procedures and goals for maintenance at the mitigation site. This maintenance program will be the responsibility of the project owner through the duration of its ownership of the mitigation area, or throughout the duration of the monitoring period, whichever is longer. The maintenance contractor will complete the work as outlined below. 4.1 MAINTENANCE WORK SCOPE 4.1.1 The primary goals of the mitigation plan are to enhance the stream buffer areas. To accomplish this goal, normal landscaping methods must be modified to include: a. No mowing or trimming of ground cover or vegetation in the mitigation area except for control of reed canary grass and other tall growing grasses in and around plantings. Reed canary grass as well as other tall grasses such as fescue, quackgrass etc. shall be cut away from base of installed plant to avoid overgrowth of the native planting. Alternatively, a water permeable fabric or cardboard disk 12"-18" in diameter may be placed around base of plant to block tall grass grow1h from competing with planting. b. No placement of fertilizers in the mitigation area. c. No placement of bark mulch or equivalent in the mitigation area, except as noted in the planting details. d. No placement of grass clippings, landscape debris, fill or ornamental plant materials in the mitigation area. 4.1.2 Work to be included in each site visit: a. Remove all litter including paper, plastic. bottles, construction debris, yard debris, etc. b. Remove all blackberry varieties and scotch broom within the mitigation area. All debris is to be removed from site and disposed in an approved landfill. c. Repair silt andlor permanent fencing and signage as needed. 4.1.3 Work to be completed on an annual basis includes: a. Areas containing Himalayan blackberry should be controlled by hand cutting the blackberry and treating the remaining cut stems only with a glyphosphate herbicide such as Roundup or Rodeo. b. Replace dead or failed plant materials. Replacement plantings are to be of same species, size and location as original plantings. Plantings are to be installed during the dormant period. 4.2 MAINTENANCE SCHEDULE The Owner will conduct all items listed in the Maintenance Work Scope on an annual basis. Additional work may be required per the Monitoring Report and as approved by the City Biologist. Additional work may include removal of the grasses around each shrub and tree, installation of wood chips at each shrub and tree base, reseeding the mitigation area, re-staking existing trees and erosion control protection. 4.3 WATERING REQUIREMENTS 4.3.1 If plantings are installed within the dormant period throughout the winter months (October through March 15th) watering is not required. 4.3.2 If plantings are installed during the summer months (March through October 1st) a temporary irrigation system will be required. The temporary irrigation system may be removed after the first year providing the plantings are established and acclimated to on-site conditions per Construction and Plantings Notes Sec. 4.0. 4.3.3 Irrigation will continue from initiation through October 1st, or between June 1st and Oct. 1st for any subsequent year. Irrigation, if required, will provide head to head coverage for 15 minutes per day every day. 4.4 CLOSEOUT OF FIVE YEAR MONITORING PROGRAM Upon completion of the monitoring program and acceptance of the buffer mitigation by the City Biologist, the maintenance of the project will be reduced to include removal of litter and debris, repair of perimeter fencing and signage, removal of noxious weeds and undesirable vegetation, and repair of vandalized areas. 5.0 MITIGATION MONITORING PROGRAM 5.1 SAMPLING METHODOLOGY The enhanced buffer will be monitored 8 times over a five year period. Monitoring will be conducted four times the first year with one monitoring report and once a year with one monitoring report each year after the first year. Monitoring will be conducted using the techniques and procedures described below to quantify the survival, relative health and growth of plant material. A monitoring report submitted following each monitoring visit will describe and quantify the status of the mitigation at that time. 5.1.1 Vegetation The vegetation monitoring consists of inspection of the planted material to determine the health and vigor of the installation. All the planted material in the buffer will be inspected during each monitoring visit to determine the level of survival of the installation. 5.2 STANDARDS OF SUCCESS 1. Evaluation of the success of the mitigation project will be based upon an 95% survival at the end of Year 1 and 80% survival of all planted woody vegetation at the end of year 5. 2. Volunteer native, non-invasive species will be included as acceptable components of the mitigation. 3. Not more than 10% non-native invasive species within the mitigation area. 5.3 CONTINGENCY PLAN A contingency plan can be implemented if necessary. Contingency plans can include regrading, additional plant installation, erosion control, additional water quality facilities, plant substitutions including type, size, and location. If the monitoring results indicate that any of the performance standards are not being met, it may be necessary to implement all or part of the contingency plan. Careful attention to maintenance is essential in ensuring that problems do not arise. Should any of the site fail to meet the success criteria, a contingency plan will be developed and implemented with the City approval. Such plans are prepared on a case-by-case basis to reflect the failed mitigation characteristics. Contingency/maintenance activities will include, but are not limited to: • Replacing all plants lost to vandalism, drought, or disease, as necessary. • Replacing any plant species with a 20 percent or greater mortality rate with the same species or similar species approved by the City Biologist. • Irrigating the enhancement area only as necessary during dry weather if plants appear to be too dry, with a minimal quantity of water. • Removing all trash or undesirable debris from the buffer areas as necessary per 4.0 Maintenance Program. FINAL NEW LIFE CHURCH -PHASE 1 WElLAND AND STREAM ANALYSIS AND MlTIGA nON REPORT CITY OF RENTON, WASHINGTON Sewa1I Wetland Consulting, Inc. 27641 Covington Way SE #2 Covington. W A 98042 Prepared For: New Life Church 15711 152nd Avenue SE Renton, WA 98058 .\Iarch S, 2010 .Job#99-101 Phone: 253-859-0515 Fax: 253-852-4732 Sewall Wetland l'~1UJ Inc. 27641 Covington Way SE #2 Covington, WA 98042 Phone: 253-859-0515 Fax: 253-852-'1732 FINAL NEW LIFE CHURCH -PHASE 1 WETLAND AND STREAM ANAI,YSIS AND MmGA TION REPORT CITY OF RENTON, WASHINGTON 1.0 INTRODUCTION 1.1 Location This report describes jurisdictional wetlands and streams on the New Life Church property located at 15025 SE Maple Valley Highway, King County, Washington. Specifically, the subject property is located in a portion of the SW \1'. of Section 23, Township 23 North, Range 5 East of the WM. in the City of Renton, King County, Washington. For the purposes of this report, the "site" is the area lying north of the steep bank that encompasses the south half of the overall New Life Church parcel. 1·' Ii" if u~· ~ Sl "e", Sf "it,' l~ I l>2lIl ~ o;r ~I ' .... ~-" -, 1.2 Proposed Use The proposed project includes the expansion of the existing church facility, parking area and storm water facility. A small amount of wetland buffer averaging will be employed along the east side of Wetland C to ofT-set impacts from the required paving of the existing tire lane. 2.0 METHODOWGY FINAL New Life Church Phase I ! # 99-1 0 I Sewall Wetland Consulting, Inc. March 5, 2010 Page 2 Ed Sewall of Sewall Wetland Consulting, Inc. delineated the wetland edges on-site on January 12, 1999. These edges were re-verified in June of 2005 and in May of 2008. The ordinary high water mark of Madsen Creek was delineated by Tonya Smith of Sewall Wetland Consulting in September of2008 and surveyed by Barghausen Consulting Engineers, Inc. in 2008. The ordinary high water mark was identified as defined by Washington State Department of Ecology and the US Army Corps of Engineers. A combination offield indicators, including vegetation, soils, and hydrology were used to determine wetland edges. The wetlands on site were identified using methodology described in the Washington Stale Wellands Identification and Delineation Manual (WADOE, March 1997). This is the methodology currently recognized by the City of Renton and the State of Washinb>ton for wetland determinations and delineations. The wetland area identitled would also be conSidered wetland using the methodology described in the Corps of Engineers We/lands Delineation Manual (Environmental Laboratory, 1987), as required by the US Army Corps of Engineers. The Washington State Wetlands Idenuticalion and Delineation Manual and the Corps of Engmeers Wetlands DeimeatlOn Manual requires the use of the three parameter approach in identifying and delineating wetlands. A wetland should support a predominance of hydrophytic vegetation, have hydric soils and display wetland hydrology. To be considered hydrophytic vegetation, over 50% of the dominant species in an area must have an indicator status offacultative (FAC), facultative wetland (FACW), or obligate wetland (OBL), according to the National List of Plant Species That Occur in Wetlands: Northwest (Region 9) (Reed, 1988). A hydric soil is "a soil that is saturated, flooded, or ponded long enough during the growing season to develop anaerobic conditions in the upper part". Anaerobic conditions are indicated in the field by soils with low chromas (2 or less), as determined by using the Munsell Soil Color Charts; iron oxide mottles; hydrogen sulfide odor and other indicators. Generally, wetland hydrology is defined by inundation or saturation to the surface for a consecutive period of 12.5% or greater of the growing season. Areas that contain indicators of wetland hydrology between 5%-12.5% of the growing season mayor may not be wetlands depending upon other indicators. Field indicators include visual observation of soil inundation, saturation, oxidized rhizospheres, water marks on trees or other fixed objects, drift lines, etc. Under normal circumstances, indicators of all three parameters will be present in wetland areas. It should be noted wetland delineations on the site were verified and approved by King County in both 2001 and 2005. 3.0 OBSERVA nONS 3. I Existin g Site Documentati on FINAL New Life Church Phase J #99·JOI Sewa ll Wetland COllsultill g. Ill c. March 5. 2010 Page 3 Prior to visiting the site, a revi ew of several natural res ource inve ntory maps was conducted . Reso urces revi ewed included t he King Co unty Soil Survey, National Wetlands Inventory Map, the Kin g Co unt y Wetland Inventory/iMap website , and the City of Renton Water Class Map. 3 . I . I Soil Survey According to the Soil Survey for the Kin g County Area , Washin/:,'Ion (S nyder e t aJ. 1973) the eastern half of the s ite is m apped as Puy allup fine sandy loam (Py) and th e western half is mapped as Newberg silt loam (Ng). Puyallup soil s are well·drained soi ls that fo nned in a lluvi um , under g ras s. hardwoods, a nd conifers. Newberg soil s are well· drained soils that fonned in allu vium in the stream va lleys, under /:,'Tass, hardwood s, and conilers. Although , Puyallup and Newhe rg so il s a re not considered hydric soils according to th e publication Hl'J/"Ic S"J!., IIf th e Unit ed Stal es (USDA NTCHS Pub No. 1491 ,1991), they can contalll inclusio ns of hydric soi ls s uc h as Briscot, Oridia, Renton, Woodinville, and Pugc t so il scrics. • ~ ... • ________ 0 __ Ahm'(': Soil Su n'f!Y map a/the site. 3.1.2 National Wetlands Inventory Map (NWI) NNAL Ne w Life Church Phase 1 1 .99-101 Sewall Wei/and Consu/ling, In c. March 5, 2010 Page 4 The NWI map for the site depicts a very small wetland classified as P ABH (palustrine, aquatic bed, pennanently floode d) ma pped off-site to the east. In addition , the NWI shows a stream along the western property boundary and a small excavated pond next to the stream on the west edge of th e s it e . "' , .................... -J/ I M a p l egend • COffU$ CloIW. D COMU! Stitt .. 1eGK I -I CONUS C~. '"11; -L_, U _,,_ POlY9O"'" t_ .. · .. ·_II .. _W .... _ ".--~-..... --. "--, .. _ .... "",, .. - I ,flII .-"" 1'0 ,.11 Ci...l ",_ .... Abol'e: NutiOfwi We fltmd Inventory Map of the site. 3.1 J King County Wetlands Inv ent o r"\"l iMap Website According to the King County We tl a nd s Inventory , there are no wetlands within 300 feet of the site. The pond areas are d ep ict e d as water bodies under "lakes and large rivers" shading. Madsen Creek is depi c ted c ro ss ing the site as a fish bearing stream (Class 2 water under City of Renton Cod e) 3.1.4 City of Renton Water C lasses Map According to the City of Renton Wa t e r C lasses Map (s ee aI/ached), Madsen Creek and the Madsen Creek overflow ch a nn e l is de picted as a Class 2 Water. These are the only streams depicted on the site or w ithi n 100' of the site . 3 .2 Field Observations -Uplan ds The eastern two-thirds of the sit e co m ist of an existing church building, parking area, and associated stonnwater facilities T he wes tern third of the site is undeveloped and includes portions of Madsen Cr eek as well as three wetlands, and their associated buffers The majority of this ar ea is dry pasture vegetated with a mix of pasture grasses including tall fescue (Fes/uca a nmdllluceu ) and orchard grass (JJa c /ylis glome ra/a). rlNAL New Life Church Phase 1 #99-101 SewaJl Wetlal/d COl/sliltil/g , fllc. March 5,2010 Page 5 AbOl'e: King Count)' iMap web ... ite acrill1 pli%Kraphs with stream and ... ",land layers turned on. 3 .3 Field Observations -Wetland s 3 .3.1 Wetland "A " Wetland "A" is in the southwest porti o n o rthe site located just east of Madsen Creek. Wetland "A" appears to be an ol d ex ca vated pond or a bermed remnant of wetland. It is connected to Wetland B, a simil a r t ype we tland located to the east, by a concrete flume type structure . Wetland "A" is c ha ra c tcri l ed by a willow (Salix la .~iandra) forest with some alder (Alnus rubra) and salmonbcrry (Rubus spe c/abilis) along the edges with an unconsolidated bottom portion III th e middle . Wetland "A" is 11 ,875 sf in size . This wetland was flagged with sequ e ntlall , n umbered pink flagging labeled AI-AI4 . Soil pits excavated within Wetla nd "A" re vealed a black (10YR 211 ) sandy loam soil. During our site visit, the soil was inund a te d to a depth of approximately 2 ' in the central portion of the wetland . Hydrol og iC Input s to this wetland include direct precipitation , runoff from the surrounding upl a nd , O\-crllow from Madsen Creek and Wetland C , and possibly some local groundwat e r d isc ha rge . Hydrologic outputs include evapo- transpiration, and possibly som e grollnd \\ater recharge . According to the United State s Fis h a nd Wildlife (USFWS ) wetland classification method (Cowardin et a1. 1979 ). th e wetland on-site would be classified as PUBX FINAL New Life Church Phas£ 1/#99-101 Sewall Weiland Consulting. Inc. March 5. 2010 Page 6 (palustrine, unconsolidated bottom, excavated), and PFO I C (palustrine, forested, broad- leaved deciduous, seasonally flooded) Wetland "A" appears to meet the criteria of a Category 3 wetland due to the fact it is a severely disturbed wetland that has had historic alteration to its hydrology. Typically, Category 3 wetlands have a 25 foot buffer measured from the wetland edge. 3.3.2 Wetland "8" Wetland "8" is an 8,400 sf scrub-shrub wetland that was delineated with flags 81-810 and is located in the southwest portion of the site located just east of Wetland "A". Wetland "8" is nearly identical in character to Wetland "A" appearing to be an old overgrown excavated pond. An old pump-house is located on one side of the wetland as well as a concrete flume connecting it to Wetland "A". The overstory vegetation in Wetland "R" consists of pacific willow <20' tall and some salmonberry. Soil pits excavated within the wetland revealed soils similar to those found in Wetland "A" and was inundated to a depth of approximately 12" in the central portion of the wetland. Hydrologic inputs to this wetland include direct precipitation, runoff from the surrounding upland, and possibly some local groundwater discharge. Hydrologic outputs include surface flow into Wetland A, evapo-transpiration, and possibly some groundwater recharge. According to the United States Fish and Wildlife (USFWS) wetland classification method (Cowardin et al. 1979), the wetland on-site would be classified as PSSIC (palustrine, scrub-shrub, broad-leaved deCiduous, seasonally flooded). Wetland "8" appears to meet the criteria of a Category 3 wetland due to the fuct it is a severely disturbed wetland that has had historic alteration to its hydrology. Typically, Category 3 wetlands have a 25 foot buffer measured from the wetland edge. 3.3.3 Wetland "C" The eastern tip of a larger forested slope type wetland that extends to the south and west was delineated with flags C l-C II. This wetland is located at the base of a steep slope and appears to be a groundwater discharge point. This wetland is characterized by scrub- shrub and forested wetland vegetation including salmonberry, willow, red-osier dogwood (Comus sio/anifera), red alder and skunk cabbage (Lysichifum americanum). Soil pits excavated within the Wetland "C" revealed a black muck soil that was inundated with up to 12" of surface water during our site visit. Water from Wetland "C" flows into FINAL New Life Church Phase 1 ! # 99-1 0 1 Sewall Wetland Consulting. Inc. March 5. 2010 Page 7 Wetland "A" through a culvert undl:r an old road that separates Wetland "C" from Wetlands "A" & "8". Hydrologic inputs to Wetland "C" include direct precipitation, runoff from the surrounding upland, and groundwater discharge. Hydrologic outputs include surface flow into Wetland "A", evapo-transpiration, and possibly some groundwater recharge. According to the United States Fish and Wildlife (USFWS) wetland classification method (Cowardin et al. 1979), the wetland on-site would be classified PFOIC (palustrine, forested, broad-leaved deciduous, seasonally flooded), and PSSIC (palustrine, scrub-shrub, broad-leaved deciduous, seasonally flooded. Wetland "C" appears to meet the criteria of a Category 2 wetland due to the fact it has minimum evidence of disturbance and has only one wetland class. Typically, Category 2 wetlands have a 50 foot buffer measured from the wetland edge. 3.3.4 Madsen Creek Madsen Creek flows through a portion of the western part of the site. This portion of the site is in the vicinity of the proposed improvements for the New Life Assembly Church. Madsen Creek flows northerly down a steep sided ravine in the southern portion of the property before turning abruptly to the east at the toe of the hillside. At the easterly bend, Madsen Creek is within several hundred feet ofthe proposed site improvements. As a result, this is the area of the site that was studied and the ordinary high water mark (OHWM) of Madsen Creek was identified and flagged. Several years ago King County DNR constructed a flood overflow structure (several culverts and a ditch) to carry excessive storm flows straight to the north along the west edge of the site from the bend of Madsen Creek at the base of the slope (the southeasterly comer of the aI/ached site plan). In a flood event, high waters in Madsen Creek would, bypass the main creek channel and flow due north in the King County-constructed bypass ditch, then under SR 169, and ultimately flow approximately 1,000' into the Cedar River. Madsen Creek main channel pas,es through the site then to the east along a series of old overgrown roadbeds, old fish ponds and herms and then flow to the north in a ditched straight line channel to SR 169. At SR 169, the channel makes a sharp tum to the west and in a meandering channel, flows westerly to the northwest comer of the site. At this point the creek passes through a culvert to the storm overflow ditch/culvert flowing westerly along the south edge of SR 169 in a ditch for several hundred feet west of the site before flowing under SR 169 in a northwesterly direction. Madsen Creek passes through the site in an altered channel configuration, although fish habitat still appears to be high. Most of the stream in the study area is a mix of glides and rimes with several small plunge pools and small cascades created by large logs. Stream bed substrate ranges from sand and small gravel to areas of cobbles where flow is FINAL New Life Church Phase I / #99-101 Sewall Weiland Consulting. Inc. March 5. 20/0 Page 8 narrow and subsequent scour is higher. Some of the gravel areas appear highly cemented with silts and clays. Stream butTer areas on the site vary in quality. The southern portion of the study area has a forested area that was historically disturbed by the creation of fish ponds along the creek, construction of berms, as well as the construction of the storm overflow channel. In this area the butTer is an immature forested plant community comprised of red alder, salmonberry, Himalayan blackberry, Indian plum, red elderberry, and hazelnut. After the creek bends to the north and flows northerly, the butTer has been highly degraded on its easterly, and to a degree, its westerlv side. As depicted on the attached site map, much of the easterly butTer is mowed lawn with a narrow band of deciduous trees, shrubs and blackberry along the east side. Several large firs are found in the lawn area. The westerly side of the creek in this area has a pasture that is occasionally mowed. Much of this butTer is heavily overgrown with blackberry. A large stand of black cottonwoods is found near just south of the proposed road crossing. This area has very dense Himalayan blackberry growth. Species known to utilize Madsen Creek include resident cutthroat trout, coho, and chum salmon. Its possible brook trout, rainbow trout and several species of sculpin and crayfish are also utilizing this stream. Wildlife species that were observed utilizing the creek habitat include raccoon, mule deer, and coyote. It is possible the upper portions of this creek support several common species of amphibians. Madsen Creek is an important fisheries stream as well as providing a corridor for wildlife through the area of the site to access undeveloped forest to the south. The butTer areas are also in providing thermal protection to the stream, a source of organic matter to the channel, an important characteristic for invertebrates which in tum support fish using this creek. The eastern butTer in portions along SR 169 appears to provide some flood attenuation during storm flows as its elevation is very close to that of the channel. However, the buffer areas along both the east and west banks along the proposed improvements are degraded in portions. Madsen Creek is a designated Class 2 water as defined by the City of Renton Code. Madsen Creek is located to the west of the proposed project and consists of a perennial salmonid bearing stream. Typically, Class 2 waters have a 100 foot buffer measured from the ordinary high water mark. 4.0 FUNCTIONS AND VALUES The overall value of wetlands on-site appears to be moderately low due to their disturbed character. However, waterfowl regularly use all of these wetlands due to the seasonal standing water as well as other wildlife species tolerant of close human contact. They FINAL New Ufe Church Phase 1/#99-101 Sewall Wetland Consulting. Inc. March 5. 2010 Page 9 also serve to store and attenuate stormwater as well as possibly store flood flows from Madsen Creek. Madsen Creek is a valuable fisheries resource, although the current buffer function is low due to its mowed lawn character on the east side of the creek. The proposed enhancement plan will preserve the existing functions of the buffer and the creek as well as improve habitat through the restoration of a native forested plant community in the stream buffer. This will improve stream shading, keeping water cooler for fish, provide organic matter and woody debris to the buffer and stream channel, as well as provide a thick vegetative barrier to human intrusion. 5.0 REGULATIONS In addition to the wetland regulations previously described for wetlands, certain activities (filling and dredging) within "waters of the United States" may fall under the jurisdiction of the u.s. Army Corps of Engineers (USACOE). The USACOE regulates all discharges into "waters of the United States" (wetlands) under Section 404(b) of the Clean Water Act. Wetlands that are hydrologically isolated are not regulated by the USACOE, per the SWANCC and as interpreted by the Corps and EPA in their Regulatory Guidance Letter. Discharges (fills) into any wetlands that are not considered "isolated" are regulated by the Corps. However, only the Corps can make that determination. Due to the increasing emphasis on Endangered Species Act compliance for all fiUs of Waters of the United State and Waters of the State, both the Corps of Engineers and Washington Department of Ecolob'Y should be contacted regarding permit conditions, compliance, and processing prior to commitment to any fill of wetlands or streams. 6.0 PROPOSED IMPACTS Al'iD MITIGATION The proposed project is the construction of a new building, additional parking areas, new frontage improvements on SR 169, and a reconstructed (enlarged) storm water facility along the east side of the site. The eastern buffers of Wetlands "B", "C" and Madsen Creek are generally degraded outside the immediate bank oflhe creek. The eastern buffer of Wetland "C" is impacted by an existing gravel driving surface (fire lane); the eastern buffer of Wetland "B" is lawn. The Wetland "B" and "C" butTers provide little function currently with the exception of filtering some runoff prior to entering these waterbodies. The project provides 1,973sf of buffer replacement south of Wetland "C" to compensate for the past and proposed reduction of 1,909sf ofbufTer east of Wetland "C". FINAL New Life Church Phase 1/#99-101 Sewalf WeIland Consulting, Inc. March 5, 2010 Page 10 The City of Renton requires frontage improvements on SR-169, a portion of which will impact existing buffer on the north side of Madsen Creek as it flows along SR-169. The existing buffer is highly degraded and consists of gravel shoulder, ditch, and maintained lawn. Although City of Renton exempts street improvements that occur in existing right- of-way from critical area regulations, the applicant has agreed to provide enhancement to the south side of the Madsen Creek butTer where it flows parallel to SR-169 (reference Final SR-169 Mitigation Plan approval issued February 2010). Wetland "c" Averaged Buffer As depicted on the Conceptual plan. the 50' buffer line for Wetland "C" extends over and beyond an existing gravel area that will be paved for fire lane for the new building. The existing gravel area to be paved is located 25' into the 50' buffer for Wetland "C". A total of I ,909 sf of Wetland "C" buffer is impacted by the proposal. To compensate for the 1,909 sf of buffer impact, 1,973 sf of wetland buffer replacement is provided on the south side of Wetland "C". [n addition, the remaining 25' buffer at the east side of Wetland "C" will be enhanced with native plantings to increase the functional value of the buffer over its current condition. As detailed in City Code, buffers on wetlands can be averaged under the following conditions; RMC 4-3-050 M.6.f. Averaging of Buffer Width: Standard wetland buffer zones may be modified by averaging hutler widths. Upon applicant request, wetland buffer width averaging may he allowed by the Department Administrator only where the applicant demonstrates all oflheliJllowing: i. That the wetland conlaml' \'Or/a/ions in ecological sen.~ilivily or there are existing physical improvemenls in or near Ihe wetland and buffer; and 11. That width averaging wi/I nO/ adversely impact the wetlandfonction and values; and iii. Thai the total area cOn/amed Within Ihe wetland buffer ajier averaging is no less than that contained witlullihe required standard buffer prior to averaging; and iv. A site specific evalualloll and dowmentation of buffer adequacy based upon The Science of Wetland Butters alld 11.1" Implications {Or the Management of" Wetland~, McMillan 20()O. or Similar approaches have been conducted The proposed buffer standard IS hased on consideration of the best available science as described in WAC 365-IY5-,)()5; or where Ihere is an absence of valid SCientific information, Ihe .11"1'.1111 RMC -I-Y-25I1F are followed. v. In no instance shalllhl! hufli'r Width be reduced by more than fifty percent (50%) of the standard buffer or he Ic.l.l Ihan twenty five feet (25') wide. Greater buffer FINAL New Life Clmrch Phase 1 / # 99-1 01 Sewall Wetland Consulting. Inc, March 5. 2010 Page 11 width reductions require review as a variance per subsection N3 of this Section and RMe -I-Y-25UB; and vi. Buffer enhancement in [he areas where the buffer is reduced .~hal/ be reqUired on a case-by-case basis where appropriate to site conditions. wetland sensitivity. and proposed land development characteristics. vii. Notification may be reqwred pursuant to subsection F8 of this Section. In response criteria RMC 4-3-050 M.6f (i) -(vii); I. The buffer of Wetland "e" has been impacted in the past to nearly the eastern edge of the wetland. Functionally, this existing buffer is already reduced to approximately 25' by the required fire lane. The proposed reduction from the 50' buffer line will not physically change the character of the buffer or its functions, which are minimal in this area because of past disturbance, It, As stated in (i) above, the buffer is already impacted by existing driving surface, an existing water line, and is vegetated with non-native plant species so the proposed buffer averaging from 50' is merely an exercise on paper and has no change in the function of the butTer. The remaining reduced buffer will be restored to a native plant community creating a higher functioning buffer at approximately 25' than the existing degraded buffer as required by Code. An increase of buffer is provided on the south side of Wetland "c" to offset the buffer averaging loss area of the fire lane to ensure that no loss of buffer function will result from the proposal and to compensate for past impacts to the buffer, iii, The total area of buffer after buffer averaging exceeds the amount of existing buffer, The total amount of buffer reduction from the past and existing condition is I ,909 sf and the replacement buffer is I ,973 sf. iv, As previously specified. the existing Wetland "c" buffer to be reduced is a mix of gravel fire lane and degraded blackberry area, This area provides no habitat function, does not filter or absorb runoff, does not provide any organic matter or woody debris to the wetland, does not have any valuable or rare plant communities, and does not provide any thermal protection nor create a barrier to human intrusion into the wetland, The proposed averaged/reduced buffer area will be restored through removal of gravel and compact material and placement of topsoiL The area to be added through averaging is 1,973sf of area of native vegetation that will be retained as buffer, When accounting for the existing degraded condition of the buffer, the proposal's provision of buller compensation will serve to improve the functional values of the resultant wetland butTer, The proposed buffer averaging is consistent with best avai lable science per WAC 365-\95-905 FINAL N~ Life Church Phase I 1#99-101 Sewall We/land Consul/ing, Inc. March 5, 2010 Page 12 v. The reduced buffer will be to 50% of the standard buffer as stipulated by Code and no less. VI. As previously described in (iv), buffer enhancement of the reduced degraded buffer is proposed. The area of proposed reduction through averaging is required to have a paved fire lane around the structure. The fire lane area is already a very low value buffer as it is primarily a gravel driving surface. The proposed lane would be located primarily in already disturbed area that is within the buffer. As a result, the reduction will remove no native vegetation. What vegetation is in this area is primarily blackberry. The proposed reduction and enhancement would include removing non-native invasive such as the blackberry and any knotweed, and replanting with native trees and shrubs. Fencing could also be provided in this area to prevent any further encroachments. The proposed reduction should not impact any of their functions of this wetland, and will result in an improvement in the plant community in this area that is degraded from past clearing and blackberry invasion. All of the proposed mitigation/enhancement areas will be monitored for 5 years as required by Code. Please refer to the I'lI1al Phase 1 Wetland Mitigation & Enhancement Plan dated October 2008 and revised March 5,20 I O. If you have any questions in regards to this report or need additional information, please feel free to contact me at (253) 859-0515 or esewall@yewallwc.com. Sincerely, Sewall Wetland Consulting, lnc. Ed Sewall Senior Wetland Ecologist PWS #212 REFERENCES Cowardin, L., V. Carter, F. Golet, and E. LaRoe. 1979. Classification of Wetlands and Deepwater Habitats of the United States. U.S. Fish and Wildlife Service, FWS/OBS-79- 31, Washington, D. C. Environmental Laboratory. \987. Corps of Engineers Wetlands Delineation Manual, Technical Report Y -87-1. U. S. Army Corps of Engineers Waterways Experiment Station, Vicksburg, Mississippi. King County Planning Division. 1983. King County Wetlands Inventory Notebook, Vol.s 1-3. King County Courthouse, Seattle, Washington. City of Renton Zoning Code. Muller-Dombois, D. and H. Ellenberg. 1974. Aims and Methods of Vegetation Ecology. John Wiley & Sons, Inc. New York, New York. Munsell Color. 1988. Munsell Soi I Color Charts. Kollmorgen Instruments Corp., Baltimore, Maryland. National Technical Committee for Hydric Soils. 1991. Hydric Soils of the United States. USDA Misc. Publ. No. 1491. Reed, P., Jr. 1988. National List of Plant Species that Occur in Wetlands: Northwest (Region 9). 1988. U. S. Fish and Wildlife Service, Inland Freshwater Ecology Section, St. Petersburg, Florida. Snyder, D., P. Gale, and R. Pringle. 1973. Soil Survey King County Area Washington. U.S.D.A., Soil Conservation Service, Washington, D.C. USDA NRCS & National Technical Committee for Hydric Soils, September 1995. Field Indicators of Hydric Soils in the United States -Version 2.1 Washington State Dept. of Ecology. 1987. Washington State Wetlands Identification and Delineation Manual. Pub. No. 96-9