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HomeMy WebLinkAboutRS_Drainage_Techincal_Information_Report_(TIR)_220525_v1.pdf TARGETED TECHNICAL INFORMATION REPORT FOR DANIEL LEE PROPERTY CITY OF RENTON, WASHINGTON Prepared by: Gina R. Brooks, P.E. Date: May 25, 2022 Revised: Core No.: 21378 5/25/2022 Core Design, Inc. DANIEL LEE PROEPRTY i DANIEL LEE PROPERTY Table of Contents 1. PROJECT OVERVIEW .......................................................................................................................... 1-1 2. CONDITIONS AND REQUIREMENTS SUMMARY ................................................................................ 2-1 2.1 Project Statistics .............................................................................................................................. 2-1 2.2 Core and Special Requirements ....................................................................................................... 2-8 For Targeted (Category 1) Drainage Review, compliance is required with the following Core and Special Requirements. ........................................................................................................................... 2-8 Core Requirements #5: Erosion and Sediment Control .................................................................... 2-8 Special Requirement #1: Other Adopted Area Specific Requirements ............................................. 2-8 Special Requirement #2: Flood Hazard Area Delineation ................................................................. 2-8 Special Requirement #3: Flood Protection Facilities ......................................................................... 2-8 Special Requirement #4: Source Control .......................................................................................... 2-8 Special Requirement #5: Oil Control ................................................................................................. 2-8 Special Requirement #6: Aquifer Protection Area ............................................................................ 2-8 3. FLOW CONTROL BMP ANALYSIS AND DESIGN .................................................................................. 3-1 4. DECLARATION OF COVENANT ........................................................................................................... 4-1 5. CSWPP ANALYSIS AND DESIGN ......................................................................................................... 5-1 6. SPECIAL REPORTS AND STUDIES ....................................................................................................... 6-1 Core Design, Inc. DANIEL LEE PROPERTY Page 1-1 1. PROJECT OVERVIEW The project site is located at 720 S 55th Street, Renton, Washington (parcel number 312305-9125) within the SE ¼ of Section 31, Township 23N, Range 5E, W.M. The property is 2.50 acres. The subject property is surrounded by residential development on all sides. Access to the property is via an easement located between parcels 3123059024 and 3123059156 extending to S 55th Street. Per City of Renton Maps, the property is located within a moderate landslide hazard area with an isolated area designated as high landslide hazard. The Maps indicate the property has some regulated slopes. Grades generally slope down towards the west. The purpose of this report is to address the unpermitted construction completed on the subject property. The current property owner performed some grading to create flat areas of yard as well as installed impervious surfaces without a permit. The City issued a code violation, CODE21-000495, for these unpermitted activities. An existing survey of the property, prior to occupation by the current property owner, was provided for assessment of the conditions prior to the unpermitted activities. The topography though, was derived from LIDAR as the existing survey appeared to have utilized LIDAR for creation of the contours. Core Design, Inc., performed a survey of the improvements to determine the extent of improvements constructed. The area of disturbance is estimated to be 36,720 square feet. This area is derived as the extent of clearing less the existing access gravel, house, and adjacent existing hard surfaces. The amount of earthwork is estimated to be 233 CY cut and 831 CY fill. The additional fill material was derived from 13504 SE 50th Place, Bellevue, WA 98006. Small block walls were installed along with the grading to create the desirable flat yard areas. Hard surfaces including gravel and pavement were placed either over existing pervious ground or existing hard surfaces. Net new pollution generating impervious surfaces placed total 7,057 square feet. A preapplication meeting (PRE22-000009) was held January 27, 2022 with notes attached within the Special Reports section of this Report. The amount of clearing, grading, and additional hard surfaces placement exceed the thresholds for Simplified and/or Targeted Drainage Review. To limit drainage review to Simplified and/or Targeted Drainage Review, portions of previously placed gravel will be removed to keep the total amount of new PGIS to less than 5,000 square feet. The subject project’s drainage facilities were designed using the guidelines and requirements established in the 2017 City of Renton Surface Water Design Manual (2017 RSWDM). Due to the site containing sensitive slopes and landslide hazard areas, the project is subject to Category 1 Targeted Drainage Review. PARCEL NO. 3123059125 ZONE: R14 ZONE: R14 ZONE: R1 ZONE: R8 ZONE: R1 PARCEL NO. 3123059024 PARCEL NO. 3123059156 ZONE: R8 ZONE: R1 DE SI GN 12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877 CIVIL ENGINEERING LANDSCAPE ARCHITECTURE PLANNING SURVEYING 720 S. 55TH ST.720 S. 55TH ST.720 S. 55TH ST.SITE AND CSWPP PLAN EARTHWORK: PARCEL NO.:3123059125 TOTAL AREA:108884 SF IMPERVIOUS LOCATED IN R8 ZONE ONLY. ZONE R8 AREA:76919 SF ZONE R8 IMPERVIOUS:*8060 SF ZONE R8 IMPERVIOUS PERCENTAGE:10% PERMITTED R8 IMPERVIOUS PERCENTAGE:65% *IMPERVIOUS ONLY INCLUDES THOSE AREAS TO REMAIN AFTER COMPLETION OF PROJECT. PARCEL NO.:3123059024 TOTAL AREA:37136 SF ZONE R1 AREA:1023 SF ZONE R1 IMPERVIOUS:516 SF ZONE R1 IMPERVIOUS PERCENTAGE:50% PERMITTED R1 IMPERVIOUS PERCENTAGE:25% ZONE R8 AREA:36113 SF ZONE R8 IMPERVIOUS:13363 SF ZONE R8 IMPERVIOUS PERCENTAGE:37% PERMITTED R8 IMPERVIOUS PERCENTAGE:65% PARCEL NO.:3123059156 TOTAL AREA:35288 SF ZONE R8 AREA:35288 SF ZONE R8 IMPERVIOUS:7289 SF ZONE R8 IMPERVIOUS PERCENTAGE:21% PERMITTED R8 IMPERVIOUS PERCENTAGE:65% IMPERVIOUS AREA BREAKDOWN: NATIVE GROWTH RETENTION AREA RESTRICTIONS AND ALLOWANCES SOIL AMENDMENT Core Design, Inc. DANIEL LEE PROPERTY Page 2-1 2. CONDITIONS AND REQUIREMENTS SUMMARY Per Figure 1.1.2.A and Table 1.1.2.A within the 2017 RSWDM, the subject project is subject to a Targeted (Category 1) Drainage Review. See copy of Figure and Table on the following pages. 2.1 Project Statistics Sensitive Areas: Per the City GIS, the site has regulated slopes and is located within a Landslide Hazard Area. No other sensitive areas were noted on the project. Core Design, Inc. DANIEL LEE PROPERTY Page 2-2 Core Design, Inc. DANIEL LEE PROPERTY Page 2-3 The site soils map below shows the site is entirely comprised of Alderwood Gravelly Sandy Loam (AgC), King County hydrologic soils group “C”, or Till soil. Core Design, Inc. DANIEL LEE PROPERTY Page 2-4 Lot Area = 108,884 square feet IMPERVIOUS CALCULATIONS PREVIOUSLY INSTALLED IMPERVIOUS Previously Installed Pvmt/Gravel (new PGIS) over Pervious = 7,057 Square Feet PROPOSED RESTORATION Convert Previously Installed Gravel to Landscaping = 2,058 Square Feet RESULTANT IMPERVIOUS SUBJECT TO DRAINAGE REVIEW New PGIS = 7,057 SF – 2,063 SF = 4,994 SF < 5,000 Square Feet Target Impervious Surfaces = 4,994 Square Feet PERVIOUS CALCULATIONS Proposed Pervious Area = 0 square feet → Previously Partially Cleared and Developed Lot Core Design, Inc. DANIEL LEE PROPERTY Page 2-8 2.2 Core and Special Requirements As the subject project requires Targeted (Category 1) Review, the Core and Special Requirements applicable to this project include those located within Simplified Review with those requirements located within Targeted (Category 1) superseding the Simplified requirements. Per coordination with the City, the Core Requirements #1-#4, and #6-#8 under the Targeted (Category 1) Review do not apply. See email correspondence on the following pages. Since the subject project requires a Simplified Drainage Review, compliance with the following two basic mitigation requirements are required. 1. Flow control BMPs per Section C.1.3: See Section 3 of this Report for the Flow Control BMP Analysis and Design. 2. Erosion and Sediment Control / Stormwater Pollution Prevention and Spill Control per Section C.1.4: See Core Requirement #5 as required for Targeted (Category 1) Drainage Review. For Targeted (Category 1) Drainage Review, compliance is required with the following Core and Special Requirements. Core Requirements #5: Erosion and Sediment Control See Section 5 of this Report for the ESC design. Special Requirement #1: Other Adopted Area Specific Requirements There are no known additional requirements for the subject project. See email correspondence on the following pages. Special Requirement #2: Flood Hazard Area Delineation Not applicable since the project does not contain nor is adjacent to a flood hazard area. Special Requirement #3: Flood Protection Facilities Not applicable since the project does not rely on an existing flood protection facility or plans to modify or construct a new flood protection facility. Special Requirement #4: Source Control Not applicable as the proposed project does not require a commercial building or commercial site development permit. As well, under a Category 1 Targeted Drainage Review, this Special Requirement is not required. Special Requirement #5: Oil Control Not applicable since the project is not a high use site. Special Requirement #6: Aquifer Protection Area Not applicable since the project is not in an Aquifer Protection Area. CAUTION: This email originated from outside the City of Renton. Do not click links, reply or open attachments unless you know the content is safe. From:Nathan Janders To:Gina Brooks Subject:RE: Daniel Lee Property - Minimum Requirements Date:Thursday, March 17, 2022 11:36:27 AM Attachments:image001.png image002.png Hi Gina, Hope you had a nice vacation. No worries on the voicemail, I was concerned that something wasn’t working right. I’d agree with your assessment on core and special requirements that are needed (additional requirements may be needed as deemed necessary through review but at this point I don’t need you to analyze them in the report). There are no ‘other adopted are-specific requirements’ that I am aware of at this location so you could list N/A for special requirement 1. Hope this helps, Regards, NATHAN JANDERS, P.E., Civil Engineer III City of Renton | CED | Planning Division 1055 S Grady Way | 6th Floor | Renton, WA 98057 Virtual Permit Center | Online Applications and Inspections (425) 430-7382 | NJanders@rentonwa.gov From: Gina Brooks <GRB@coredesigninc.com> Sent: Thursday, March 17, 2022 11:06 AM To: Nathan Janders <NJanders@Rentonwa.gov> Subject: RE: Daniel Lee Property - Minimum Requirements Nathan, Thanks for getting back to me. I was scrambling prior to my vacation all of last week and thought I had left a voicemail but, then realized I did not. My bad. Based on your email below, Core Reqmt #5 is required, along with Special Reqmts #1-#4, and #6. Correct? Can you tell me what the “Other Adopted Area-Specific Requirements” are for this project? This is Special Requirement #1. Thanks, Gina R. Brooks, P.E. Associate, Sr. Project Engineer Core Design Inc. O 425.885.7877 www.coredesigninc.com From: Nathan Janders <NJanders@Rentonwa.gov> Sent: Friday, March 4, 2022 3:53 PM To: Gina Brooks <GRB@coredesigninc.com> Subject: RE: Daniel Lee Property - Minimum Requirements CAUTION: This email originated from outside the City of Renton. Do not click links, reply or open attachments unless you know the content is safe. Hi Gina, Everything that is checked in the category 1 review is required to be addressed, however, it may not be applicable see footnote 3. For the asterisked core requirements, at this point I don’t see a need for any of the others. Also I checked and hadn’t received a voicemail. Hope you have a good weekend, NATHAN JANDERS, P.E., Civil Engineer III City of Renton | CED | Planning Division 1055 S Grady Way | 6th Floor | Renton, WA 98057 Virtual Permit Center | Online Applications and Inspections (425) 430-7382 | NJanders@rentonwa.gov From: Gina Brooks <GRB@coredesigninc.com> Sent: Tuesday, March 1, 2022 11:45 AM To: Nathan Janders <NJanders@Rentonwa.gov> Subject: Daniel Lee Property - Minimum Requirements Nathan, Not sure if your office phone is monitored as I left a message last week. Hoping this email finds you. I am struggling to understand which minimum requirements apply to this project. This project falls under Category 1 Targeted Drainage Review. The requirements noted with * are determined by the City. Can you tell me if these relevant requirements apply and if so, which ones? We will be reducing our PGIS to below 5,000 square feet as a heads up. Does Special Requirement 1 apply? I would really appreciate the guidance as I wrap my hands around the scope of this work. Thanks so much, Gina R. Brooks, P.E. Associate, Sr. Project Engineer Core Design Inc. O 425.885.7877 www.coredesigninc.com Core Design, Inc. DANIEL LEE PROPERTY Page 3-1 3. FLOW CONTROL BMP ANALYSIS AND DESIGN The subject project is required to meet the Large Lot BMP Requirements per the 2017 RSWDM Section C.1.3.2 as the lot is larger than 22,000 square feet. Flow control BMPs must be applied to the project’s target impervious surface in the following order of preference: 1. The feasibility and applicability of Full dispersion must be evaluated for all target impervious surfaces on the site/lot. Full dispersion is not feasible since the maximum slope criteria for the full dispersion credit is exceeded within the area of the site that is native ground. 2. Where full dispersion of target impervious roof areas is not feasible or applicable, or will cause flooding or erosion impacts, the feasibility and applicability of full infiltration must be evaluated for the roof area. Targeted surfaces do not include roof area. This BMP is therefore not applicable. 3. All target impervious surfaces not mitigated by Requirements 1 and 2 above, must be mitigated to the maximum extent feasible using one or more BMPs from the following list. • Full Infiltration • Limited Infiltration • Bioretention • Permeable Pavement As the site is located within a Landslide Hazard Area, Full Infiltration, Limited Infiltration, Bioretention, and Permeable Pavement are infeasible and not required. 4. All target impervious surfaces not mitigated by Requirements 1,2 and 3 above, must be mitigated to the maximum extent feasible using the Basic Dispersion BMP. As the site is located within a Landslide Hazard Area, Basic Dispersion is infeasible and not required. 5. BMPs must be implemented, at minimum, for impervious area amounts defined as follows: a) For projects that will result in an impervious surface coverage on the buildable portion of the site/lot of less than 45%, flow control BMPs must be applied to 50% of target impervious surfaces. b) For projects that will result in an impervious surface coverage of 45% to 65% on the buildable portion of the site/lot, flow control BMPs must be applied to 50% of target impervious surfaces reduced by 1.5% for each 1% of impervious surface coverage above 45% (e.g., impervious coverage of 55% results in a requirement of FCBMPs applied to 35% of target impervious surfaces). c) For projects that will result in an impervious surface coverage greater than 65% on the buildable portion of the site/lot, flow control BMPs must be applied to 20% of the target impervious surfaces or to an impervious area equal to at least 10% of the site/lot, whichever is less. Core Design, Inc. DANIEL LEE PROPERTY Page 3-2 The buildable portion of the site/lot is the total area of the site/lot minus any critical areas and minus 200 foot buffer areas from a steep slope hazard, landslide hazard area, or erosion hazard area. If these minimum areas are not mitigated using feasible BMPs from Requirements 1, 2, 3, and 4 above, one or more BMPs from the following list are required to be implemented to achieve compliance. These BMPs must be implemented as part of the proposed project. • Reduced Impervious Surface Credit • Native Growth Retention Credit • Tree Retention Credit Per coordination with the City, via email dated, April 20th, 2022, the preference for BMP mitigation is the Native Growth Retention Credit with easement sized 4:1 to the targeted impervious surfaces. See email attached on the following pages. This NGR area has been delineated on the Site Plan. The area of targeted impervious surfaces is 4,994 SF resulting in a required easement area of 4*4,994 SF = 19,976 SF. This easement will be placed along the west side of the property as requested by the City. 6. The soil moisture holding capacity of new pervious surfaces must be protected in accordance with the soil amendment BMP. Soil amendment will be incorporated into all disturbed areas not covered with hard surfaces. Previously disturbed surfaces currently stabilized with vegetation shall not receive soil amendment unless otherwise required by the City. 7. Any proposed pipe connection of roof downspouts to the local drainage system must be via a perforated pipe connection. Targeted surfaces do not include roof area. This BMP is therefore not applicable. CAUTION: This email originated from outside the City of Renton. Do not click links, reply or open attachments unless you know the content is safe. From:Nathan Janders To:Gina Brooks Cc:Daniel Daikyu lee Subject:RE: Daniel Lee Property - BMP Struggles and Thoughts Date:Wednesday, April 20, 2022 5:11:17 PM Attachments:image001.png Gina yes, you’ve understanding of my recommendation is correct and is conceptually shown here in red (note it’s not to scale): NATHAN JANDERS, P.E., Civil Engineer III City of Renton | CED | Planning Division 1055 S Grady Way | 6th Floor | Renton, WA 98057 Virtual Permit Center | Online Applications and Inspections (425) 430-7382 | NJanders@rentonwa.gov From: Gina Brooks <GRB@coredesigninc.com> Sent: Wednesday, April 20, 2022 2:00 PM To: Nathan Janders <NJanders@Rentonwa.gov> Cc: Daniel Daikyu lee <daikyulee@gmail.com> Subject: RE: Daniel Lee Property - BMP Struggles and Thoughts Nathan, I want to make sure I understand. 1. For the Native Growth Retention, the multiplier is 3.5. You are proposing 4. Is this correct? I am assuming that is the case but, want to confirm. 2. The NGR would be approximately 207’ (west property boundary length) by 97’ located along the west boundary of the property. Can you confirm this is what you are suggesting? Thanks again for all your help. Sincerely, Gina R. Brooks, P.E. Associate, Sr. Project Engineer Core Design Inc. O 425.885.7877 www.coredesigninc.com From: Nathan Janders <NJanders@Rentonwa.gov> Sent: Wednesday, April 20, 2022 10:34 AM To: Gina Brooks <GRB@coredesigninc.com> Subject: RE: Daniel Lee Property - BMP Struggles and Thoughts Hi Gina, I apologize, this slipped past me. I don’t think that piecemailing small portions of sheet flow and native growth are efficient or desired. Even though the slopes do exceed 15% for a majority of the property we would rather see a native growth that is one consistent area as you describe. Given that the western side of the property is currently densely vegetated and is on the downhill side of the property, we would be willing to accept a native growth easement proposed over this area sized at 4:1 (NGPE : target impervious or 19,976 SF based on 4,994 SF) in lieu of the piecemailed, feasible, BMP’s. Let me know if you want to discuss further and I can set up a call, Regards, NATHAN JANDERS, P.E., Civil Engineer III City of Renton | CED | Planning Division 1055 S Grady Way | 6th Floor | Renton, WA 98057 Virtual Permit Center | Online Applications and Inspections (425) 430-7382 | NJanders@rentonwa.gov From: Gina Brooks <GRB@coredesigninc.com> Sent: Thursday, April 7, 2022 3:03 PM To: Nathan Janders <NJanders@Rentonwa.gov> CAUTION: This email originated from outside the City of Renton. Do not click links, reply or open attachments unless you know the content is safe. Subject: RE: Daniel Lee Property - BMP Struggles and Thoughts Nathan, Checking in. Can you give me a heads up when you will be able to review my email below. Would be super helpful to get timing. Thanks so much, Gina R. Brooks, P.E. Associate, Sr. Project Engineer Core Design Inc. O 425.885.7877 www.coredesigninc.com From: Gina Brooks Sent: Thursday, March 31, 2022 4:58 PM To: 'Nathan Janders' <NJanders@Rentonwa.gov> Subject: Daniel Lee Property - BMP Struggles and Thoughts Nathan, I reviewed what we discussed in our meeting and still struggling quite a bit with these BMPs but, may be getting closer to a solution. Please see attached exhibit. We need to mitigate 4,994 SF of impervious after removal of some of the gravel to get us below 5,000 square feet. We are proposing this removal. For the Native Growth Retention, there are very few areas on the site 15% or less. See attached for location of those areas. The total of these areas mitigate for 2,260 SF. If we utilize sheet flow dispersion, as shown on the attached, along the driveway within the access and the driveway extending to the west within the property, I can possibly mitigate for 3,546 SF if we are permitted to grade a small area of slope exceeding 15% as shown. If we could utilize the sheetflow dispersion as delineated on the exhibit, we would need to mitigate for 4994 SF – 3546 SF = 1448 SF within Native Growth Retention. The area of Native Growth Retention would need to be a min of 3.5*1,448 SF = 5,068 SF. We could group some of the less than 15% areas together to create logical areas of Native Growth Retention. These areas would include areas that are 15% and less along with areas exceeding 15%. Not sure if you are tracking me here. For these Native Growth Retention Areas we would create, we would only count the areas of 15% towards the credit but, designated areas would be larger. What do you think? Sincerely, Gina R. Brooks, P.E. Associate, Sr. Project Engineer Core Design Inc. O 425.885.7877 www.coredesigninc.com Core Design, Inc. DANIEL LEE PROPERTY Page 4-1 4. DECLARATION OF COVENANT The Declaration of Covenant for the Native Growth Retention Area Easement is attached on the following pages. Page 1 of ___ Return Address: City Clerk’s Office City of Renton 1055 S Grady Way Renton, WA 98057 DECLARATION OF COVENANT FOR INSPECTION AND MAINTENANCE OF DRAINAGE FACILITIES AND ON-SITE BMPS Grantor: Grantee: City of Renton, a Washington municipal corporation Legal Description: Assessor's Tax Parcel ID#: IN CONSIDERATION of the approved City of Renton (check one of the following) Residential Building Permit Commercial Building Permit Clearing and Grading Permit Civil Construction or Utility Permit for Permit(s)_____________________ (Construction/Building/Utility Permit #) relating to the real property ("Property") described above, the Grantor(s), the owner(s) in fee of that Property, hereby covenants (covenant) with the City of Renton (“City of Renton” or “City”), a municipal corporation of the state of Washington, that he/she (they) will observe, consent to, and abide by the conditions and obligations set forth and described in Paragraphs 1 through 9 below with regard to the Property, and hereby grants (grant) an easement as described in Paragraphs 2 and 3. Grantor(s) hereby grants (grant), covenants (covenant), and agrees (agree) as follows: 1.The Grantor(s) or his/her (their) successors in interest and assigns ("Owners ") shall at their own cost, operate, maintain, and keep in good repair, the Property's drainage facilities constructed as required in the approved construction plans and specifications __________________ (Project Plan #) on file with the City of Renton and submitted to the City of Renton for the review and approval of permit(s) _____________________________ (Construction/Building/Utility Permit #). The Property's drainage facilities are shown and/or listed on Exhibit A – Site Plan. The Property’s drainage facilities shall be maintained in compliance with the operation and maintenance schedule included and attached herein as Exhibit B – Operations and Maintenance. Drainage facilities include pipes, channels, flow control facilities, water quality facilities, on-site best management practices (BMPs) and other engineered structures designed to manage and/or Page 2 of ___ treat stormwater on the Property. On-site BMPs include dispersion and infiltration devices, bioretention, permeable pavements, rainwater harvesting systems, tree retention credit, reduced impervious surface footprint, vegetated roofs and other measures designed to mimic pre-developed hydrology and minimize stormwater runoff on the Property. 2.City of Renton shall have the right to ingress and egress over those portions of the Property necessary to perform inspections of the stormwater facilities and BMPs and conduct maintenance activities specified in this Declaration of Covenant and in accordance with the Renton Municipal Code. City of Renton shall provide at least thirty (30) days’ written notice to the Owners that entry on the Property is planned for the inspection of drainage facilities. After the thirty (30) days, the Owners shall allow the City of Renton to enter for the sole purpose of inspecting drainage facilities. In lieu of inspection by the City, the Owners may elect to engage a licensed civil engineer registered in the state of Washington who has expertise in drainage to inspect the drainage facilities and provide a written report describing their condition. If the engineer option is chosen, the Owners shall provide written notice to the City of Renton within fifteen (15) days of receiving the City’s notice of inspection. Within thirty (30) days of giving this notice, the Owners, or engineer on behalf of the Owners, shall provide the engineer’s report to the City of Renton. If the report is not provided in a timely manner as specified above, the City of Renton may inspect the drainage facilities without further notice. 3.If City of Renton determines from its inspection, or from an engineer’s report provided in accordance with Paragraph 2, that maintenance, repair, restoration, and/or mitigation work is required to be done to any of the drainage facilities, City of Renton shall notify the Owners of the specific maintenance, repair, restoration, and/or mitigation work (“Work”) required pursuant to the Renton Municipal Code. The City shall also set a reasonable deadline for the Owners to complete the Work, or to provide an engineer’s report that verifies completion of the Work. After the deadline has passed, the Owners shall allow the City access to re-inspect the drainage facilities unless an engineer’s report has been provided verifying completion of the Work. If the Work is not completed within the time frame set by the City, the City may initiate an enforcement action and/or perform the Work and hereby is given access to the Property for such purposes. Written notice will be sent to the Owners stating the City’s intention to perform such Work. This Work will not commence until at least seven (7) days after such notice is mailed. If, within the sole discretion of the City, there exists an imminent or present danger, the seven (7) day notice period will be waived and Work will begin immediately. 4.The Owners shall assume all responsibility for the cost of any Work, or any measures taken by the City to address conditions as described in Paragraph 3. Such responsibility shall include reimbursement to the City within thirty (30) days of the receipt of the invoice for any such Work performed. Overdue payments will require payment of interest at the maximum legal rate allowed by RCW 19.52.020 (currently twelve percent (12%)). If the City initiates legal action to enforce this agreement, the prevailing party in such action is entitled to recover reasonable litigation costs and attorney’s fees. 5.The Owners are required to obtain written approval from City of Renton prior to filling, piping, cutting, or removing vegetation (except in routine landscape maintenance) in open vegetated stormwater facilities (such as swales, channels, ditches, ponds, etc.), or performing any alterations or modifications to the drainage facilities referenced in this Declaration of Covenant. Page 3 of ___ 6.Any notice or consent required to be given or otherwise provided for by the provisions of this Agreement shall be effective upon personal delivery, or three (3) days after mailing by Certified Mail, return receipt requested. 7.With regard to the matters addressed herein, this agreement constitutes the entire agreement between the parties, and supersedes all prior discussions, negotiations, and all agreements whatsoever whether oral or written. 8.This Declaration of Covenant is intended to protect the value and desirability and promote efficient and effective management of surface water drainage of the real property described above, and shall inure to the benefit of all the citizens of the City of Renton and its successors and assigns. This Declaration of Covenant shall run with the land and be binding upon Grantor(s), and Grantor's(s') successors in interest, and assigns. 9.This Declaration of Covenant may be terminated by execution of a written agreement by the Owners and the City that is recorded by King County in its real property records. IN WITNESS WHEREOF, this Declaration of Covenant for the Inspection and Maintenance of Drainage Facilities is executed this _____ day of ____________________, 20_____. GRANTOR, owner of the Property GRANTOR, owner of the Property STATE OF WASHINGTON ) COUNTY OF KING )ss. On this day personally appeared before me: , to me known to be the individual(s) described in and who executed the within and foregoing instrument and acknowledged that they signed the same as their free and voluntary act and deed, for the uses and purposes therein stated. Given under my hand and official seal this _____ day of ___________________, 20_____. Printed name Notary Public in and for the State of Washington, residing at My appointment expires PARCEL NO.3123059125MATCHLINE, SEE UPPER RIGHTMATCHLINE,SEE LOWER LEFTEXHIBIT A - SITE PLAN720 S. 55TH STREET MAINTENANCE INSTRUCTIONS FOR NATIVE GROWTH RETENTION CREDIT Your property contains an on-site BMP (best management practice) known as “native growth retention,” the practice of preserving a portion of a property in a native vegetated condition (e.g., forest) so as to minimize increases in stormwater runoff from clearing and to offset the stormwater runoff impacts caused by impervious surfaces on your property. This native vegetated area on your property was set aside by covenant as “native growth retention area.” This on-site BMP shall be maintained per Appendix A of the City of Renton’s Surface Water Design Manual. MAINTENANCE RESTRICTIONS The “native growth retention area” is delineated on the site plan attached to the covenant. The trees, vegetation, ground cover, and soil conditions in this area may not be disturbed, except as allowed by the following provisions: 1. Trees may be harvested in accordance with a King County-approved forest management plan if approved by King County prior to annexation to the City. 2. Individual trees that have a structural defect due to disease or other defects, and which threaten to damage a structure, road, parking area, utility, or place of employment or public assembly, or block emergency access, may be topped, pruned, or removed as needed to eliminate the threat. 3. Dead or fallen trees, tree limbs within ten feet of the ground, and branches overhanging a residence may be removed to reduce the danger of wildfire. 4. Noxious weeds (i.e., plant species listed on the State noxious weed list in Chapter 16-750 WAC) and invasive vegetation (i.e., plant species listed as obnoxious weeds on the noxious weed list adopted by King County) may be removed. 5. Passive recreation uses and related facilities, including pedestrian, equestrian community and bicycle trails, nature viewing areas, fishing and camping areas, and other similar uses that do not require permanent structures, are allowed if clearing and soil compaction associated with these uses and facilities does not exceed eight percent of the native growth retention area. RECORDING REQUIREMENT These native growth retention credit on-site BMP maintenance and operation instructions must be recorded as an attachment to the required declaration of covenant and grant of easement per Requirement 3 of Section C.1.3.4 of the City of Renton Surface Water Design Manual. The intent of these instructions is to explain to future property owners, the purpose of the BMP and how it must be maintained and operated. These instructions are intended to be a minimum; the City of Renton) may require additional instructions based on site-specific conditions. See the City of Renton’s Surface Water Design Manual website for additional information and updates. Page 6 of _6__ Exhibit C - Legal Description For APM/Parcel ID(s): 312305-9125-02 LOT 3 OF SHORT PLAT NO. 674217, RECORDED MARCH 17, 1975 UNDER RECORDING NO. 7603170525, BEING A PORTION OF THE SOUTHEAST QUARTER OF THE SOUTHEAST QUARTER OF SECTION 21, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M. IN KING COUNTY, WASHINGTON. SITUATE IN THE COUNTY OF KING, STATE OF WASHINGTON. Core Design, Inc. DANIEL LEE PROPERTY Page 5-1 5. CSWPP ANALYSIS AND DESIGN Per Section 1.2.5.1, Construction Stormwater Pollution Prevention (CSWPP) measures include Erosion and Sediment Control (ESC) measures and Stormwater Pollution Prevention and Spill (SWPPS) measures. Design of the CSWPP plan was completed in conformance with Section 2.3.1.1.TIR Section 8 of the 2017 RSWDM. ESC PLAN ANALYSIS AND DESIGN (PART A) Design of the ESC plan was completed in conformance with Core Requirement #5 and Appendix D of the 2017 City of Renton Surface Water Design Manual. Compliance with the 13 ESC measures is summarized below. 1. Clearing Limits: Clearing limits have been delineated on sheet 1 of the construction plans. The clearing limits extend only to those areas that were previously disturbed during previous construction of the subject project. 2. Cover Measures: Temporary Cover and Permanent Cover measures are specified as notes on sheet 2 of the construction plans. 3. Perimeter Protection: Silt fence will be used for perimeter protection. Silt fence will be installed along the perimeters of those areas that will be receiving silt-laden runoff. See sheet 1 of the construction plans for location. 4. Traffic Area Stabilization: The existing driveway will be utilized for construction access. 5. Sediment Retention: Silt fence was utilized for sediment retention for the entire area of previous disturbance. The disturbed area has since been vegetated with grass. As the site has average slopes of 13%, per the 2017 RSWDM Section D.2.1.3, silt fence can be utilized as primary treatment for a sheet flow distance of 228 feet. There is a small portion of site that is in excess of this flow distance but, since the previously disturbed area has since been planted with grass, the concerns for erosion has passed. Silt fence has been added to the end of the previously placed driveway of which a portion of that previously placed gravel will be removed and revegetated. The flow distance for this proposed disturbed area is 70 feet at 11% average grade. For 11%, silt fence can be utilized as primary treatment for a sheet flow distance over 200 feet. 6. Surface Water Collection: Surface water collection is not necessary as drainage remains in a sheet flow condition and previously disturbed area has since been vegetated with grass. The small area of future disturbance does not warrant collection. 7. Dewatering Control: A note on sheet 2 of the construction plans addresses dewatering control. 8. Dust Control: A note on sheet 2 of the construction plans addresses the procedure for dust control should soils become too dry. 9. Flow Control: This measure is not applicable as the site is exempt from any permanent flow control facilities. 10. Control Pollutants: See SWPPS Plan Design (Part B) below. Core Design, Inc. DANIEL LEE PROPERTY Page 5-2 11. Protect Existing and Proposed Flow Control BMPs: A Native Growth Retention Area has been provided at the west end of the property. The proposed construction activity is not anticipated to create any disturbance of this area. 12. Maintain BMPs: Notes have been added to sheet 2 of the construction plans addressing maintenance requirements. 13. Manage the Project: The project will be managed based on seasonal work limitations and continual inspection and monitoring throughout the project. SWPPS PLAN DESIGN (PART B) The CSWPPS plan contains notes establishing what materials and activities will not be allowed on the site along with notes describing BMPs for treatment of materials and activities that will be allowed on the site. The contractor shall designate a person as the responsible representative in charge of erosion control and maintenance of all erosion control and stormwater pollution prevention facilities, see CSWPP plan. Pollution-generating activities associated with construction and mitigation are tabulated below. 1. Storage and Handling of Liquids: Stormwater Pollution Prevention Notes have been added to sheet 2 of the construction plan set addressing storage and handling of liquids. 2. Storage and Stockpiling of Construction Materials and Wastes: Storage of construction materials and wastes will be stored within a designated stockpile area. Stockpile areas shall be covered with plastic when not in use. Stockpile height shall not exceed 8 feet. 3. Fueling: Stormwater Pollution Prevention Notes have been added to sheet 2 of the construction plan set addressing fueling. 4. Maintenance, Repairs, and Storage of Vehicles and Equipment: Stormwater Pollution Prevention Notes have been added to sheet 2 of the construction plan set addressing maintenance, repairs, and storage of vehicles and equipment. 5. Concrete Saw Cutting, Slurry, and Washwater Disposal: Stormwater Pollution Prevention Notes have been added to sheet 2 of the construction plan set addressing concrete saw cutting, slurry, and washwater disposal. 6. Application of Chemicals including Pesticides and Fertilizers: Stormwater Pollution Prevention Notes have been added to sheet 2 of the construction plan set addressing application of chemicals. 7. Handling of pH Elevated Water: Stormwater Pollution Prevention Notes have been added to sheet 2 of the construction plan set addressing pH elevated water. Core Design, Inc. DANIEL LEE PROPERTY Page 6-1 6. SPECIAL REPORTS AND STUDIES The following documents are located on the following pages. • Preapplication meeting (PRE22-000009) Notes CityofRenton\Department Folders\Community and Economic Development (CED)\Current Planning\Pre-Applications\2021\PRE22- 000009\Working Files 1 PRE-APPLICATION MEETING FOR Lee Code Compliance PRE22-000009 CITY OF RENTON Department of Community & Economic Development Planning Division January 27, 2022 Contact Information: Planner: Alex Morganroth, 425-430-7219, amorganroth@rentonwa.gov Public Works Plan Reviewer: Nate Janders, 425-430-7382, njanders@rentonwa.gov Fire Prevention Reviewer: Corey Thomas, 425-276-9582, cthomas@rentonrfa.org Building Official: Rob Shuey, 425-430-7290, rshuey@rentonwa.gov Please retain this packet throughout the course of your project as a reference. Consider giving copies of it to any engineers, architects, and contractors who work on the project. You will need to submit a copy of this packet when you apply for land use and/or environmental permits. Pre-screening: When you have the project application ready for submittal, call and schedule an appointment with the project manager to have it pre-screened before making all of the required copies. The pre-application meeting is informal and non-binding. The comments provided on the proposal are based on the codes and policies in effect at the time of review. The applicant is cautioned that the development regulations are regularly amended and the proposal will be formally reviewed under the regulations in effect at the time of project submittal. The information contained in this summary is subject to modification and/or concurrence by official decision-makers (e.g., Hearing Examiner, Planning Director, Development Services Director, Department of Community & Economic Development Administrator, Public Works Administrator and City Council). CityofRenton\Department Folders\Community and Economic Development (CED)\Current Planning\Pre-Applications\2021\PRE22- 000009\Working Files 2 DEPARTMENT OF COMMUNITY & ECONOMIC DEVELOPMENT M E M O R A N D U M DATE: October 7, 2021 TO: Alex Morganroth, Senior Planner FROM: Nathan Janders, Engineering Plan Reviewer SUBJECT: Daniel Lee Grading 720 S 55th St PRE22-000009 NOTE: The applicant is cautioned that information contained in this summary is preliminary and non- binding and may be subject to modification and/or concurrence by official City decision-makers. Review comments may also need to be revised based on site planning and other design changes required by City staff or made by the applicant. I have completed a preliminary review for the above-referenced proposal located at parcel(s) 3123059125. The following comments are based on the pre-application submittal made to the City of Renton by the applicant. Water 1. The proposed project does not impact on the water utility. Sanitary Sewer 1. The proposed project does not impact on the sewer utility. Surface Water 1. There are no existing on-site conveyance systems. 2. There is an existing 12-inch stormwater main on the north side of S 55th St (no record drawing available). 3. Critical areas on site that may affect stormwater review include: landslide hazard, regulated slopes. 4. Drainage plans and a drainage report complying with the adopted 2017 Renton Surface Water Design Manual will be required. Refer to Figure 1.1.2.A – Flow Chart of the 2017 Renton Surface Water Design Manual (RSWDM) to determine what type of drainage review is required for this site. The site falls within the City’s Flow Control Duration Standard Area - Matching Forested. The site falls within the Black River drainage basin. 5. If the new plus replaced pollution generating impervious surface exceeds 5,000 SF, the applicant will be required to provide basic water quality treatment. Any proposed detention and/or water quality vault shall be designed in accordance with the RSWDM that is current at the time of civil construction permit application. Separate structural plans will be required to be submitted for review and approval under a separate building permit for the detention and/or water quality vault. 6. Appropriate on-site BMPs satisfying Core Requirement #9 will be required to help mitigate the new runoff created by this development to the maximum extent feasible. On-site BMPs shall be evaluated as described in CityofRenton\Department Folders\Community and Economic Development (CED)\Current Planning\Pre-Applications\2021\PRE22- 000009\Working Files 3 Section C.1.3 of the 2017 RSWDM. A preliminary drainage plan, including the application of on-site BMPs, shall be included with the land use application, as applicable to the project. A geotechnical soils report for the site is required per the 2017 Renton Surface Water Design Manual Section C.1.3. 7. Erosion control measures to meet the City requirements shall be provided. 8. The current Surface Water Standard Plans shall be used in all drainage plan submittals. The current City of Renton Standard Details are available online in the City of Renton website 9. https://edocs.rentonwa.gov/Documents/Browse.aspx?id=990403&dbid=0&repo=CityofRenton. 10. A Construction Stormwater Permit from Department of Ecology is required if clearing and grading of the site exceeds one acre. 11. The development is subject to a surface water system development charge (SDC) fees. Fees will be charged based on the rate at the time of construction permit issuance. • The 2022 SDC fee is $0.84 per square foot of new impervious surface not to exceed $2,100. • The full fee schedule can be found at: https://edocs.rentonwa.gov/Documents/DocView.aspx?id=9010319&dbid=1&repo=CityofRenton Transportation 1. The proposed project is exempt from street improvements. General Comments 1. If frontage improvements are required, all existing and proposed utility lines (i.e. electrical, phone, and cable services, etc.) along property frontage or within the site must be underground as outlined in RMC 4-6-090 – UTILITY LINES - UNDERGROUND INSTALLATION. The construction of these franchise utilities must be inspected and approved by a City of Renton inspector. 2. Adequate separation between utilities as well as other features shall be provided in accordance with code requirements. a. 7-ft minimum horizontal and 1-ft vertical separation between storm and other utilities is required with the exception of water lines which require 10-ft horizontal and 1.5-ft vertical. b. The stormwater line should be minimum 5 feet away from any other structure or wall or building. c. Trench of any utility should not be in the zone of influence of the retaining wall or of the building. 3. All construction utility permits for utility and street improvements will require separate plan submittals. All utility plans shall confirm to the Renton Drafting Standards. A licensed Civil Engineer shall prepare the civil plans. Please visit the Development Engineering Forms page for the most up-to-date plan submittal requirements: http://rentonwa.gov/business/default.aspx?id=42473 4. A landscaping plan shall be included with the civil plan submittal. Each plan shall be on separate sheets. 5. Fees quoted in this document reflect the fees applicable in the year 2022 only and will be assessed based on the fee that is current at the time of the permit application or issuance, as applicable to the permit type. Please visit www.rentonwa.gov for the current development fee schedule. CityofRenton\Department Folders\Community and Economic Development (CED)\Current Planning\Pre-Applications\2021\PRE22- 000009\Working Files 4 DEPARTMENT OF COMMUNITY & ECONOMIC DEVELOPMENT M E M O R A N D U M DATE: January 25, 2022 TO: Pre-Application File No. 22-000009 FROM: Alex Morganroth, Senior Planner SUBJECT: Daniel Lee Code Compliance Parcel# 3123059125 We have completed a preliminary review of the pre-application for the above-referenced development proposal. The following comments on development and permitting issues are based on the pre -application submittals made to the City of Renton by the applicant and the codes in effect on the date of review. The applicant is cautioned that information contained in this summary may be subject to modification and/or concurrence by official decision-makers (e.g., Hearing Examiner, Community & Economic Development Administrator, Public Works Administrator, Planning Director, Development Services Director, and City Council). Review comments may also need to be revised based on site planning and other design changes required by City staff or made by the applicant. The applicant is encouraged to review all applicable sections of the Renton Municipal Code. The Development Regulations are linked here and are available online at https://www.codepublishing.com/WA/Renton/. Project Proposal: The subject property is located at 720S 55th St. The project site (APN 3123059125) totals 2.5 acres in area and is located within the Residential – 1 (R-1), Residential – 8 (R-8), and Residential – 14 (R-14) zoning classifications. The western portion of the site is located within the Talbot Urban Separator Overlay district. An existing single-family home is located on the eastern portion of the site. Access to the site is provided via a private driveway off of S 55th St which crosses the adjacent property (3123059024) to the south of the project site. Two Warning of Violations were issued on September 28, 2021 for site grading without erosion control measures installed and grading/excavation/mining without a grading license or permit (CODE21-000495). According to the project narrative submitted by the applicant, grading and installation of various impervious surfaces occurred on the site resulting in approximately 36,720 feet of ground disturbance. The total amount of earthwork was estimated by the applicant at approximately 233 cubic yards cut and 831 cubic yards of fill. In addition, small block walls were installed in order to create the flat yard surface to west of the existing home. Gravel was placed within the existing driveway and yard area, and approximately 3,143 sq. ft. of new pavement was installed adjacent to the attached garage. According to the applicant, the value of the work performed was equal to approximately $12,000. COR maps indicates presence of a moderate landslide hazard, a high landslide hazard, sensitive slopes, and protected slopes on the site. Based on the site plan provided, it is unclear whether trees were removed as part of the project. Current Use: The subject property contains a single-family dwelling and associated yard area on the eastern portion of the site, while the western portion of the site is densely vegetated with a steep slope running east to west. Zoning: The property is located within the Residential Low Density (LD), Residential Medium Density (MD), and Residential High Density (HD) comprehensive plan land use designations. The parcel has zoning designations of Residential – 1 (R-1), Residential – 8 (R-8), and Residential – 14 (R-14). The western portion of the site is located in the Talbot Urban Separator Overlay district (overlaps with R-1 zoned portion of site). According to the applicant, all CityofRenton\Department Folders\Community and Economic Development (CED)\Current Planning\Pre-Applications\2021\PRE22- 000009\Working Files 5 work completed on the site was within either the R-1 or R-8 zoning designations, with some minor grading occurring the Urban Separator Overlay district. Development Standards: The project would be subject to RMC 4-2-110A, “Development Standards for Residential Zoning Designations” effective at the time of complete application (noted as “R-1, R-8 and R-14 standards” herein). Due to the nature of the project, which did not the construction of any new buildings or additions, only development standards related to the completed grading and impervious improvements are included below. For a complete list of development standards, see RMC 4-2-110A. Building Standards – The R-1 standards allow a maximum building coverage of 20% of the lot area. The maximum impervious surface coverage in the R-1 zone is 25%. The R-8 standards allow a maximum building coverage of 50% of the lot area. The maximum impervious coverage in the R-8 zone is 65%. The R-14 standards allow a maximum building coverage of 65% of the lot area. The maximum impervious surface coverage in the R-14 zone is 80%. Impervious surface requirements would be verified at the time of land use review. The applicant shall demonstrate that both the subject property as well as the adjacent property on which the private driveway extends do not exceed the impervious surface maximums for the zone. Landscaping: With the exception of critical areas, all pervious area shall have landscape treatment. Landscaping may include hardscape such as decorative paving, rock outcroppings, fountains, plant containers, etc. Ten feet (10') of on-site landscaping is required along all public street frontages. Minimum planting strip widths between the curb and sidewalk are established according to the street development standards of RMC 4-6-060. Street trees and, at a minimum, groundcover shall be planted within planting strips and there shall be a minimum of one street tree planted per lot. A conceptual landscape plan shall be provided with the formal land use application as prepared by a registered Landscape Architect or other certified professional. Significant Tree Retention: If significant trees are proposed to be removed, a tree inventory and a tree retention plan along with a tree retention worksheet shall be provided with the formal land use application. The tree retention plan must show preservation of at least 30 percent (30%) of significant trees. The Administrator may authorize the planting of replacement trees on the site if it can be demonstrated to the Administrator's satisfaction that an insufficient number of trees can be retained. In addition to retaining 30% of existing significant trees, the lot would be required to provide a minimum tree density of two (2) trees per 5,000 square feet of lot area onsite. Significant trees shall be retained in the following priority order: Priority One: Landmark trees; significant trees that form a continuous canopy; significant trees on slopes greater than twenty percent (20%); Significant trees adjacent to critical areas and their associated buffers; and Significant trees over sixty feet (60') in height or greater than eighteen inches (18") caliper. Priority Two: Healthy tree groupings whose associated undergrowth can be preserved; other significant native evergreen or deciduous trees; and other significant non-native trees. Priority Three: Alders and cottonwoods shall be retained when all other trees have been evaluated for retention and are not able to be retained, unless the alders and/ or cottonwoods are used as part of an approved enhancement project within a critical area or its buffer. The Administrator may require independent review of any land use application that involves tree removal and land clearing at the City's discretion. If staff determines that the trees cannot be retained, replacement trees, with at least a 2-inch caliper or an evergreen at least 6 feet tall, shall be planted at a rate of 12 caliper inches of new trees to replace each protected tree removed. A formal tree retention plan prepared by an arborist or landscape architect would be reviewed at the time of the formal land use application if any trees were removed as part of the project. CityofRenton\Department Folders\Community and Economic Development (CED)\Current Planning\Pre-Applications\2021\PRE22- 000009\Working Files 6 Fences/Walls: If the applicant installed any fences or retaining walls as part of this project, the location must be designated on the landscape plan or grading plan. A fence and/or wall detail should also be included on the plan. A retaining wall that is 4 feet or taller, as measured by the vertical distance from the bottom of the footing to the finish grade at the top of the wall requires a building permit. A fence shall not be constructed on top of a retaining wall unless the total combined height of the retaining wall and the fence does not exceed the allowed height of a standalone fence. For more information about fences and retaining walls refer to RMC 4-4-040. Retaining wall heights for residential development are limited to 6-feet in height for interior side yards and rear yards and 4-feet in height front yards and side or rear yards along a street. Terrace widths must be equal to the wall height and landscaped. Retaining walls shall be composed of brick, rock, textured or patterned concrete, or other masonry product that complements the proposed building and site development. Driveways and Parking: The maximum width of single loaded garage driveways shall not exceed nine feet (9') and double loaded garage driveways shall not exceed sixteen feet (16'). Except for joint use driveways, driveways shall not be closer than five feet (5') to any property line. Maximum driveway slopes shall not exceed fifteen percent (15%); provided, that driveways exceeding eight percent (8%) shall provide slotted drains at the lower end with positive drainage discharge to restrict runoff from entering the garage/residence or crossing any public sidewalk. To exceed fifteen percent (15%), a variance is required. Each lot would be required to provide a minimum of two (2) parking spaces. A maximum of 4 vehicles may be parked on a lot, including those vehicles under repair and restoration, unless kept within an enclosed building. Access: Access to the lot is currently provided via an existing private gravel driveway that crosses the adjacent lot the south (APN 3123059024) and connects the subject lot to S 55th St. Approximately 2,540 sq. ft. of new gravel material was added to the driveway according to the applicant. Urban Separator Overlay: The project site is mapped within the Talbot Urban Separator Overlay. The intent is to provide physical and visual distinctions between Renton and adjacent communities, define Renton’s boundaries and create contiguous open space corridors within and between urban communities, which provide environmental, visual, recreational and wildlife benefits. Standards within Entire Urban Separator a. Forest/vegetation clearing shall be limited to a maximum of thirty five percent (35%) of the gross acreage of the site except: i. The percentage of forest/vegetation coverage may be increased to qualify for the density bonus allowed in RMC 4-2-110E. ii. Modification of the percentage of forest/vegetation retention may be approved if determined necessary to meet the surface water retention/detention standards of RMC 4-3-110E5d of this Section. iii. Forest/vegetation clearing greater than thirty five percent (35%) of individual building sites may be approved to allow grading for a home site; provided, that: (a) A landscape plan is provided for each building site showing compensating replanting of species with the same or better water retention and erosion control functions; (b) Five percent (5%) additional replacement landscaping per site is provided; (c) Plant caliper is sufficient to achieve needed water retention and erosion control functions; (d) Individual trees or stands of trees are retained when feasible. Feasibility is defined as locations and tree health sufficient to ensure continued viability of the tree and safety of structures within the developed portion of the lot; and (e) The landscape plan provides massing of plant material to create either a connection to required open space or is of sufficient size to create functional wildlife habitat. CityofRenton\Department Folders\Community and Economic Development (CED)\Current Planning\Pre-Applications\2021\PRE22- 000009\Working Files 7 b. If the existing cleared area of a site, as of March 21, 2005, is greater than thirty five percent (35%), approval of a plat shall require replanting of forest/vegetative cover. c. Forest/vegetation cover may include a combination of Northwest native vegetation including conifer, deciduous trees and shrubs sufficient to provide water retention and erosion control. If existing vegetation is found to be insufficient to meet forest/vegetation coverage standards, additional plantings shall be required. d. Stormwater management shall comply with the Surface Water Design Manual. e. Private access easements and improvements shall be established at the minimum standard needed to meet public safety requirements. f. Landscape plans required in RMC 4-4-070 shall include retention/replanting plans as applicable, consistent with standards and plant lists in King County Department of Natural Resources and Parks Water and Land Resources Division Publication “Going Native.” Critical Areas: High and moderate landslide hazard areas and sensitive and protected slopes (grades between 25 and 90 percent) are mapped on the project site. A 15-foot structure setback is required for protected slopes. In addition, protected slopes and their associated buffers shall be placed in a Native Growth Projection Area (protective easement). A geotechnical report will be required at the time of formal land use application due to the alteration of a high landslide area. It is the applicant responsibility to ascertain whether or not there are additional critical areas located on site. Grading, Excavation and Mining Regulations: All grading activities shall be subject to the standards and regulations contained in RMC 4-4-060 Grading, Excavation and Mining Regulations. For any mining, excavation or grading in excess of five hundred (500) cubic yards, the Hearing Examiner shall review, approve, disapprove, or approve with conditions the location of the site and its effect on the surrounding area. To grant a special permit, the Hear ing Examiner shall make a determination that: Compatibility of Proposed Use: The proposed activity would not be unreasonably detrimental to the surrounding area. The Hearing Examiner shall consider, but is not limited to, the following: i. Size and location of the activity. ii. Traffic volume and patterns. iii. Screening, landscaping, fencing and setbacks. iv. Unsightliness, noise and dust. v. Surface drainage. vi. The length of time the application of an existing operation has to comply with nonsafety provisions of Title IV Development Regulations. Cut Standards from RMC 4-4-060.M 1. General: Unless otherwise recommended in the approved soil engineering and/or engineering geology report, cuts shall conform to the provisions of this Section. 2. Maximum Slope: The slope of cut surfaces shall be no steeper than is safe for the intended use. Except in conjunction with a modification granted per RMC 4-9-250D1 for one of the circumstances listed in RMC 4-3- 050N2a(ii) (Geologic Hazards – Modifications), cut operations associated with a plat, short plat, subdivision or dedication, or other permitted land development activity which would result in the creation of permanent slopes CityofRenton\Department Folders\Community and Economic Development (CED)\Current Planning\Pre-Applications\2021\PRE22- 000009\Working Files 8 forty percent (40%) or greater which are fifteen feet (15') in height, i.e., protected slopes, shall not be approved. (Amd. Ord. 4835, 3-27-2000) 3. Drainage and Terracing: Drainage and terracing shall be provided as required by subsection N of this Section. Fill Regulations from RMC 4-4-060.N 1. Applicability and Exemptions: Unless otherwise recommended in the approved soil engineering report, fills shall conform to the provisions of this Section. In the absence of an approved soil engineering report, these provisions may be waived for minor fills not intended to support structures. For minor fills or waste areas, humps, hollows or water pockets shall be graded smooth with acceptable slopes. 2. Fill Location: Fill slopes shall not be constructed: a. On natural slopes steeper than two-and-one-half horizontal to one vertical (2.5:1) that are fifteen feet (15') or greater in height (except in conjunction with a modification granted per RMC 4-9-250D1 for filling against the toe of a natural rock wall – see RMC 4-3-050N2a(ii)(b)); or b. Where the fill slope toes out within twelve feet (12') horizontally of the top of existing or planned cut slopes that are fifteen feet (15') or greater in height and steeper than two -and-one-half horizontal to one vertical (2.5:1). (Amd. Ord. 4835, 3-27-2000; Ord. 4851, 8-7-2000) 3. Preparation of Ground: The ground surface shall be prepared to receive fill by removing vegetation, noncomplying fill, topsoil and other unsuitable materials as determined by the soil engineer, and where the slopes are five to one (5:1) or steeper, by benching into sound bedrock or other competent material, provided native vegetation and significant trees are protected pursuant to RMC 4-4-130. (Ord. 5828, 12-12-2016) 4. Fill Material: Fill material shall be subject to the following standards and requirements: a. General: Fill materials shall have no more than minor amounts of organic decomposable substances and shall have no rock or similar irreducible material with a dimension greater than eight inches (8"). Material used in fills shall be appropriate for the site and the intended use of that portion of the site. b. Construction, Demolition, and Land Clearing Waste Prohibited: Fill material shall be free of construction, demolition, and land clearing waste except that this requirement does not preclude the use of recycled concrete rubble from a Washington State Department of Transportation approved source. c. Cleanliness of Fill Material: Fill material shall not contain concentrations of cont aminants that exceed cleanup standards for soil specified in WAC 173-340-740, Model Toxics Control Act. No solid waste, hazardous waste, hazardous material, or materials categorized as dangerous waste under WAC Title 173 shall be used as fill. d. The Administrator may specify other characteristics of the fill material used, the degree of compaction, the moisture content, and the method of placement based on the intended use of the portion of the site where the fill will be placed and the requirements for water retention, drainage control, and erosion control. e. Fill Material Source Statement for Projects Located in Zone 1 of the Aquifer Protection Area Involving the Placement of More than Fifty (50) Cubic Yards of Imported Fill: A fill material source state ment is required for projects located in Zone 1 of the Aquifer Protection Area if more than fifty (50) cubic yards of imported fill will be used; the documentation shall be certified by a professional engineer or geologist licensed in the State of Washington. The fill material source statement shall be provided to the Department and shall be reviewed and accepted by the Department prior to stockpiling or grading imported fill at the project site. The fill material source statement, as defined in RMC 4-8-120D19, shall be required for each source location from which imported fill will be obtained. f. Fill Material Source Statement for Projects Located in Zone 2 of the Aquifer Protection Area Involving Placement of More than One Hundred (100) Cubic Yards of Imported Fill: A fill material source statement is CityofRenton\Department Folders\Community and Economic Development (CED)\Current Planning\Pre-Applications\2021\PRE22- 000009\Working Files 9 required for projects located in Zone 2 of the Aquifer Protection Area if more than one hundred (100) cubic yards of imported fill will be used; the documentation shall be certified by a professional engineer or geologist licensed in the State of Washington. The fill material source statement shall be reviewed and accepted by the Department prior to stockpiling or grading imported fill at the project site. The fill material source statement, as defined in RMC 4-8-120D19, shall be required for each source location from which imported fill will be obtained. g. Abbreviated Source Statement for Aquifer Protection Area: The Department may accept a fill material source statement, as defined in RMC 4-8-120D19, that does not include results of sampling and analysis of imported fill if a professional geologist or engineer licensed in the State of Washington certifies that the source location from which fill will be obtained has never been filled, developed, or subjected to use that could have introduced chemical contamination to the site. h. Department Authority to Request Additional Information or Reject Certified Source Statement: The Department has the authority to request additional information regarding imported fill material and the source thereof and to reject a fill material source statement or an abbreviated version if they do not demonstrate that the fill material to be imported to a project site meets fill material standards of this Section and/or the Department has reason to suspect that the fill material could be contaminated. Such requests or rejections shall be made in writing to the applicant. i. Source Statement Not Required for Imported Fill Obtained from Washington State Department of Transportation Approved Source: The source statement defined in RMC 4-8-120D19 is not required for those projects located in the aquifer protection area if documentation is provided that imported fill will be obtained from a Washington State Department of Transportation appro ved source. (Amd. Ord. 4851, 8-7- 2000) j. Sampling and Analysis Procedures: The licensed professional engineer or geologist or person under their supervision who samples earth materials to be used as imported fill, oversees analysis, and prepares a fill material source statement required by this Section shall follow procedures specified in WAC 173 -340-820 and 173-340-830 of the Model Toxics Control Act – Cleanup regulations. k. Required Actions after Illegal Placement of Imported Fill: A person who stockpiles or grades imported fill at the site without Department review and acceptance of a fill material source statement required by this Section or who stockpiles or grades fill at the site that does not meet the fill quality standards of this Section is subject to measures specified by the Department to reduce risk of contamination of the site due to illegal placement of fill. Such measures may include, but are not limited to, any or all of the following and shall be implemented at the person’s expense: i. Provide the Department with a fill material source statement defined in RMC 4-8-120D19 within a time period specified by the Department; ii. Immediately cover fill with a waterproof cover; iii. Immediately remove fill; iv. Installation of monitoring wells and monitoring of ground water quality; v. Remediation of contamination of the site caused by the illegal placement of fill according to a schedule specified by the Department and in accordance with cleanup standards for soil and groundwater described in the Model Toxics Control Act – Cleanup regulations, chapter 173-340 WAC. l. Department Authority to Conduct Independent Sampling and Analysis: The Department shall have the authority to enter onto private property to conduct independent sampling and analysis o f fill. If the Department determines that fill does not meet fill quality standards of this Section, then it may require the person to accomplish any or all of the measures listed in this Section at his or her own expense. CityofRenton\Department Folders\Community and Economic Development (CED)\Current Planning\Pre-Applications\2021\PRE22- 000009\Working Files 10 m. Department Authority to Implement Removal and Remediation Measures: The Department or its authorized agents shall have the authority to implement measures listed in this Section if the person fails to accomplish such measures in a timely manner. The permittee shall be responsible for any costs incurred by the Department or its authorized agents in the conduct of such activities. (Amd. Ord. 4740, 7 -19-1999; Ord. 4992, 12-9-2002; Ord. 5954, 11-18-2019) 5. Minimum Compaction: All fills shall be compacted to a minimum of ninety five percent (95%) of maximum density as determined by American Public Works Association (APWA) specifications. Field density shall be determined in accordance with APWA standards. Exceptions to the compaction requirement include soils below areas set aside for low impact development best management practices designed consistent with RMC 4-6-030. (Ord. 5828, 12-12- 2016) 6. Maximum Slope: The slope of fill surfaces shall be no steeper than is safe for the intended use. Except in conjunction with a modification granted per RMC 4-9-250D1 for one of the circumstances listed in RMC 4-3- 050N2a(ii) (Geologic Hazards – Modifications), fill operations associated with a plat, short plat, subdivision or dedication, or other permitted land development activity which would result in the creation of permanent slopes forty percent (40%) or greater which are fifteen feet (15') in height, i.e., protected slopes, shall not be approved. (Amd. Ord. 4835, 3-27-2000) 7. Drainage and Terracing: Drainage and terracing shall be provided and the area above fill slopes and the surfaces of terraces shall be as required by subsection N of this Section. (Ord. 5526, 2-1-2010) Environmental Review: The proposal exceeds the City’s adopted categorical exemption thresholds (RMC 4-9-070G) and is subject to State Environmental Policy Act (SEPA) Review in accordance with WAC 197-11-800. In addition, the presence of critical areas on the site necessitates SEPA review. An environmental checklist must be submitted with the land use application. Permit Requirements: The proposal would a Hearing Examiner Special Grade and Fill Permit and Environmental (SEPA) Review. The applications would be reviewed concurrently within an estimated time frame of 12 weeks. The 2022 Hearing Examiner Special Grade and Fill Permit application fee is $5,410.00 (+ 5% technology fee). The 2022 Environemntal (SEPA) Review fee is $1,600.00 (+5% technology fee). Each modification request is $262.50 ($250.00 each plus a 5% Technology Surcharge Fee). All fees are subject to change. Detailed information regarding the land use application submittal can be found on the City’s new website by clicking “Land Use Applications” on the Community & Economic Development page, then “All Forms (A to Z).” The City now requires electronic plan submittal for all applications. The City’s Electronic File Standards can also be found on the City’s website at https://edocs.rentonwa.gov/Documents/Browse.aspx?startid=867190&dbid=0. Public Notice: The applicant is required to install a proposed land use action sign on the subject property per the specifications provided in the public information sign handout. The applicant is solely responsible for the construction, installation, maintenance, removal, and any costs associated with the sign. See the Public Information Sign handout on the City’s website for more information and specifications. Next Steps: When the formal application materials are complete, the applicant shall have the materials pre- screened virtually prior to submitting the complete application package. Please contact Alex Morganroth, Senior Planner at 425-430-7219 or amorganroth@rentonwa.gov to schedule a virtual prescreen appointment. Expiration: The special permit shall be null and void if the applicant has not begun activity within six (6) months after the granting of the permit, unless the Hearing Examiner grants an extension of time. Special permits are valid until the approved plans have been satisfactorily completed.