Loading...
The URL can be used to link to this page
Your browser does not support the video tag.
Home
My WebLink
About
Misc
TECHNICAL INFORMATION REPORT for NE 24th 3-Lot Short Plat LUA14-001654, SHPL-A April 6, 2015 Revised 4/24/15 Revised 5/13/15 Encompass Engineering Job No. 14690 Prepared For Bill Hughes 14401 Issaquah-Hobart RD Issaquah, WA 98027 Western Washington Division 165 NE Juniper St., Ste 20 l, Issaquah, WA 98027 Phone: (425) 392-0250 Fax: (425) 391-3055 www .EncompassES.net Eastern Washington Division I 08 East 2"• Street, Cle Elum, WA 98922 Phone: (509) 674-7433 Fax: (509) 674-7419 SECTION I: SECTION II: SECTION III: SECTION IV: SECTION V: SECTION VI: SECTION VII: SECTION VIII: SECTION IX: SECTIONX: • TABLE OF CONTENTS PROJECT OVERVIEW CONDITIONS AND REQUIREMENTS SUMMARY OFF-SITE ANALYSIS FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN CONVEYANCE SYSTEM ANALYSIS AND DESIGN SPECIAL REPORTS AND STUDIES OTHER PERMITS ESC ANALYSIS AND DESIGN BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT OPERATIONS AND MAINTENANCE MANUAL SECTION 1 PROJECT OVERVIEW Site Address: King County Tax Parcels: Project Overview 24XX NE 24th St., Renton, WA 98059 813210-0120 and 813210-0130 This project involves the development of two vacant parcels totaling 0.58 acres into three single- family lots in the Kennydale area. These parcels are located within Northeast Section 05, Township 23 North, Range 5 East, W.M. The existing topography of these parcels generally slopes down to northwest at approximately 10%to 25%. The existing parcels are vacant and is covered with lawn and several mature trees. Per the USDA Web Soil Survey, the site is underlain with Indianola fine to medium sand. -Refer to Sec. 6 of this TIR for geotech report and infiltration test results prepared by Geo Resources. Proposed Drainage Controls Stormwater will be controlled on the joint driveway with the plat infrastructure construction and in the future with individual lot infiltration trenches, to be constructed with future residential building permits. A design in included in this TIR including a detail of the infiltration trench and a linear feet callout for each 1,000 sq-ft of impervious surface to be constructed. 2009 KC (Renton) SWDM Core Requirements Section 1.2.1 Core Requirement # I : Discharge at the natural location The site drainage will continue to infiltrate into the ground. Section 1.2.2 Core Requirement #2: Offsite Analysis An offsite drainage analysis is provided in this Preliminary TIR. Section 1.2.3 Core Requirement #3: Flow Control Individual infiltration trenches will be used on each lot for flow control. Section 1.2.4 Core Requirement #4: Conveyance System The conveyance analysis will be provide in the final TIR as needed. Section 1.2.5 Core Requirement #5: Erosion and Sediment Control A temporary erosion control plan will provide BMP's to be implemented during construction. Section 1.2.6 Core Requirement #6: Maintenance and Operations A maintenance and operations manual is in the TIR for int onsite infiltration. Section 1.2. 7 Core Requirement #7: Financial Guarantees and Liability The developer will arrange for any financial guarantees and liabilities required by the permit. Section 1.2.8 Core Requirement #8: Water Quality Because there will be less than 5,000 sq-ft of PGIS, water quality measures will not be needed. 2009 KC SWDM Special Requirements Section 1.3 .I NIA Special Requirement# I: Other Adopted Area-Specific Requirements Section 1.3.2 Special Requirement #2: Floodplain/Floodway Delineation N/A there are no FEMA floodplains/floodways in the area Section 1.3.3 Special Requirement #3: Flood Protection Facilities NIA Section 1.3.4 Special Requirement #4: Source Control Source control is not required for this SFR project. Section 1.3.5 Special Requirement #5: Oil Control Oil control is not required for this SFR project. Section 1.3.6 Special Requirement #6: Aquifer Protection Area Even though the projectin in AP A Zone 2, because there will be less than 5,000 sq-ft of PG.JS, liners or or other restrictions relating to soil meeting max/min infiltration rates and/or cation exchange criteria do not apply that might for a larger project. --REPLACE TREES -(6) 2" CALIPER DECIDUOUS OR a' HIGH CONIFER TREES REQUIRED PLAT OF" SI.INSET H•LLS VOL 169. PG 52 LOT 'l ~-L au210-a,10 EX. 5' CYClONE FENCE 183{) NE 1TH ST APPRQx_ LOCATION EX. SEV,£ff STU6 EX. CUFIB/5" Sl!JEWAUC/6.:5' PLANTER STRIP TD REMMN EX. CB RIM-285.72 INV-283 72 (6"PVC-NE) INV-28:2.02 (6-ADS-S) Ol.. 'NA T£R METkR FOR 1SJO ,I[ 24TH ST " ORIVEWAY ({) 0 z 0 S 10 20 LOT 1c ----,.,,c " / / / EltZ!iX: / / GRADE / / )'·,x> / / '"' / / ( / v ~"07'.20'W 48.oo· T.L 8T 3210-01,Q LOT 1 7,02J so. l'T. 100'-6" PIIC O 2.0o,i; -SEE C..0.R. sro. PLAN 4-05 FOR BEDDING: SPECS. .• I,,' APPROX. 1..0CATJON OF i'UTURE LOT 2P 5' WIDE INFlURAllON TRENCHES 1 (14A I.F lRENCtt/1,000 SQ. rr. IMPERVIOUS \SURFACE) -NO FlU. Al.LOEJ IN THESE .-RtAS \ I I 1.1 TL. Bl:3210--0140 EX. 6' WOOO "ENCE LOT 3 HS.62 91.t2' \ _;::~~ON /""STL /11J210-01JO I / / // / f-5• PVC OVERFLOW / / I ' I / / / / 4 / LOT 2 v I: f 1 I~ I : f 1 ,..:'.;;: 10" PRIVATE I I 2.5" DRAINAGE EA&:.~~ 1 : 31: r I-is~~~N~~E MENT :Egn~;r~~~!~ rn> I ~ .j_j APPRO LOCATIOII I • ~ 11 I REC. 110. 946 01977. T'fl'. f E.<. ~ 0 PER CITY RECORDS I VI 1 CLB\NOUT iE-284.96:1: I 10' El£CTillC EASEMENT I _ I R~ N~ 9~02~2'._ _ _l+: NEW ORI\IEWA Y ~ 8 • SO I 7' . cc I DRIVEWAY r APPROX. LOCATION Ex. SEWER STUB -SAWCUT AND RESTORE PA\oEMErH PER C.O.R. sros. 10·' TIUTY EASEMENT .c::, REC :: ~~977 l - NEW 1• "'"" """' FOR LOT J EX. STREET TREE TO BE 1110\oEO ..1 TO DRIVEWAY REMOVAL AREA I 1_ .JJ~J90-22114 1"l JJ4390-2281 CBI 1, TYPE I :"-°~&RNfD mows (ALL P rt,tv .. zga.oo (O\.'ERFLOW) !NV,.,297.75 {!Nfn..lRATIQN LINE) 'L. 802620-0120 ~ +---llWROX. LOCATION OF . EX. 8" WATER !6' ~NT f-t---,4d-~T~~(1~l~{ j I FOR LOT 2\3 ACCESS r':cf-r---"+--~;,to":'ff 2~~6e1css -SEE SECTION SHEET 4 " DRIVEWAY REPLACE SIC TO NEI'/ ORll -SEE DETAIL WATER MANHOL RlM=JOl,47 TOP OF VALVE~ INV-297.47 (12 EX. STORM MANliOl.£ RIM-J02.09 IN\lm298.99 (12-ADS-E&W EX. STORM M RIM=JOJ.06 1r-iv~2sus ( INV-291.J1 (1 "--"--1,;>'--------'"----:~ APPROX. LOCA 710N OF EX. 12" WATER UGHT !>OLE TO SE R~CATED FOR lo' MIN. "'""""' FROM DRIVEWAYS II!' DRl\oEWAY ENlRANCE PER C.O.R. SID PLAN 104.3 LOT 26 T.L B02SS5-0260 ,,. DRIVEWAY l PLAT :l'F STONE CASTl(. VOL 200, PCS 59··61 LOT 27 r L. 802955-0270 '" " . Site Plan 1" = 40' I CN CN R-8, , \ R-1 9, 0 ZONING MAP BOOK PLANNING • TECHNICAL SERVICES PRINTED DATE: 10/0212013 This dowmentis a graphicrepresentaion, not gua-mteed to survey accuracy, and 1$ base:I Oil the best information alllli!able as afthe date shown. Thia map Is inteMed ro; City display P!JltlOSEISOnlv. Communn:y & Economic Development R-8 R-8 C4E 32 T24N R5E E 112 RC R-8 ' ··"·-, I" R-8 R-14 R-14 Vicinity Map E4E 08 T23N RSE E 1/2 0 420 la-...!.. Feet '" ' D4E 1:8,780 05 T23N R5E E 112 Page 12of80 City Limits D (COR) CommerdaL'Office/Residential D (R-4) Residential 4du/ac CJ RENTON D (CV) Center Village D (R-S) Residential 8du/ac c.Potentia!Annexalion Area D (IHJ /nci.lsbial Heavy D (RC) Resourre Co11Wrvatlon Zoning Designation .t:J OLJ Industrial Light D (Rl.t.F) Re.sidenlial Multi-Family D (CA/ Commemial.Arterial D [lM) Industrial Medium D (RM-T} Resi. Mulli-F,mify Tradifcm1/ D (CD) CanterDownlDwn D (R-1) Residential 1du/ac D (RM-U) Resl. Multi-F.mlly urban Center c:J {CNJ Commercial Neighbortiood c:J (R-10) Residential todu/ac D (Rt.Iii) Residential Manufactured Hames D (CO) Commercial Office D (R-14) ResidenLia! 14du/ac; D IUC-N1) Urll.in Genier Nor1tl 1 D (UC·N2) Urban Cl!llW'" Nath 2 D "' er:. :a: 'is! -; "' "' z ;,:, "' m :a: N t SECTION 2 CONDITIONS AND REQUIREMENTS SUMMARY DEPARTMENT OF COMMUNITY AND ECONOMIC DEVELOPMENT , -· City of ADMINISTRATIVE SHORT PLAT REPORT & DECISION A. SUMMARY AND PURPOSE OF REQUEST REPORT DATE: Project Name: Project Number: Project Manager: Owner: Applicant: Contact: Project Location: Project Summary: Exist. Bldg. Area SF: Site Area: March 6, 2015 NE 24th Street Short Plat LUA14-001654, SHPL-A Jill Ding, Senior Planner John Cowan, 1830 NE 24th Street, Renton, WA 98056 Bill Hughes, 14401 Issaquah-Hobart Road, Issaquah, WA 98027 Tom Redding, Encompass Engineering & Surveying, 165 NE Juniper Street, Suite 201, Issaquah, WA 98027 1904 and 1908 NE 24th Street Subdivision of an existing 25,400 square foot (0.58 acre) project site zoned R-8 (Residential-8 dwelling units per acre) into three lots for the future construction of three single family residences. The project site consists of two vacant parcels on the north side of NE 24th Street (parcel nos. 8132100120 and 8132100130). An 18-foot wide private driveway is proposed on the eastern portion of proposed Lot 2 to provide access to proposed Lot 3. A variance was requested from the Fire Dept to reduce the paving width required for the private driveway access to Lot 3 from 20 feet to 16 feet. Access to Lots 1 and 2 would be provided via residential driveways off of NE 24th Street. A street modification request has been submitted to allow the existing frontage improvements to remain along NE 24th Street. Sensitive slopes (grades between 25 and 40 percent), high landslide hazard areas, moderate landslide hazard areas, and Aquifer Protection Area 2 are mapped on the project site. N/A 25,400 sq. ft. Proposed New Bldg. Area (footprint}: Proposed New Bldg. Area (gross}: Total Building Area GSF: Unknown N/A N/A ----------~~ ~---------- SHPL Report 14-001654 v2 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision LUA14-001654, SH Pl-A Report of March 6, 2015 B. EXHIBITS: Short Plat Report Exhibit A.1: Exhibit A.2: Exhibit A.3: Staff Report Neighborhood Detail Map Short Plat Plan (dated December 24, 2014) Page 2 of 21 Exhibit A.4: Conceptual Drainage Control, Generalized Utility and Grading Plan (dated December 15, 2014) Exhibit A.5: Exhibit A.6: Exhibit A. 7: Landscape Plan (dated December 2014) Tree Cutting/Land Clearing Plan (December 15, 2014) Tree Retention Worksheet Exhibit A.8: Geotechnical Engineering Report, prepared by GeoResources, LLC (dated 12/22/2014) Exhibit A.9: Preliminary Technical Information Report, prepared by Encompass Engineering & Surveying, dated December 29, 2014 Exhibit A.10: Street Modification Request Exhibit A.11: Street Modification Approval Letter C. GENERAL INFORMATION: 1. Owner(s) of Record: John Cowan 1830 NE 24th Street Renton, WA 98056 2. Zoning Designation: Residential -8 dwelling units per acre (R-8) 3. Comprehensive Plan Land Use Designation: Residential Single Family (RSF) 4. Existing Site Use: Vacant 5. Neighho.rhood Characteristics: a. North: Single-family residential (R-8/ b. East: Single-family residential (R-8} c. South: Single-family residential (R-8} d. West: Singlefamily residential (R-8} 6. Access: NE 24th Street 7. Site Area: 2S,400 sf D. HISTORICAL/BACKGROUND: Action Comprehensive Plan SHPL Reoort 14-001654 v2 Land Use File No. N/A Ordinance No. 5100 Date 11/01/2004 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision LUA14-001654, SHPL·A Report of March 6, 2015 Zoning Annexation Interim Zoning N/A N/A N/A E. APPLICABLE SECTIONS OF THE RENTON MUNICIPAL CODE: 1. Chapter 2 Land Use Districts 5099 1818 5724 a. Section 4-2-020: Purpose and Intent of Zoning Districts b. Section 4-2-070: Zoning Use Table c. Section 4-2-110: Residential Development Standards d. Section 4-2-115: Residential Design and Open Space Standard 2. Chapter 3 Environmental Regulations and Overlay Districts a. Section 4-3-050: Critical Area Regulations 3. Chapter 4 Property Development Standards a. Section 4-4-030: Development Guidelines and Regulations b. Section 4-4-070: landscaping c. Section 4-4-130: Tree Retention and Land Clearing Regulations 4. Chapter 6 Streets and Utility Standards a. Section 4-6-060: Street Standards 5. Chapter 7 Subdivision Regulations a. Section 4-7-070: Detailed Procedures for Short Subdivisions Page 3 of 21 11/01/2004 03/17/1960 09/22/2014 b. Section 4-7-120: Compatibility with Existing Land Use and Plan -General Requirements and Minimum Standards c. Section 4-7-150: Streets -General Requirements and Minimum Standards d. Section 4-7-170: Residential Lots -General Requirements and Minimum Standards 5. Chapter 11 Definitions F. APPLICABLE SECTIONS OF THE COMPREHENSIVE PLAN: 1. Land Use Element: 2. Community Design Element: G. DEPARTMENT ANALYSIS: Residential Single Family Established Residential Neighborhoods and New and Infill Development 1. Project Description/Background The applicant has proposed to subdivide a 0.58 acre (25,400 square foot) site located within the Residential -8 dwelling units per acre (R-8) zone. The proposal would create 3 lots intended for the development of detached single-family residences. The project site is currently vacant. After the deduction of the 1,763 square foot private access easement, the proposal for 3 lots on the project site would result in a net density of 5.6 dwelling units per acre. Proposed Lot 1 would total 7,023 square feet in area, Lot 2 would total 7,004 square feet in area, and Lot 3 would total 9,610 square feet in area. SHPL Repo1t 14-001654 v2 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Shott Plat Report & Decision LUA14-001654, SHPL-A Page 4 of 21 City Council adopted Ordinance 5724 to provide interim zoning standards for the R-8 zone. The legislation and interim standards became effective at the time of Council approval on September 22, 2014. The NE 24th Street Short Plat application was determined a complete application on January 8, 2015, after the adopted of the interim zoning standards, and therefore, is vested to the interim zoning standards (Ordinance 5724) as well as the standards adopted under Ordinance 5702. Access for Lots 1 and 2 would be provided via new driveways off of NE 24th Street. Access to Lot 3 is proposed via a 16-foot wide private access easement over the east side of Lot 2. Existing frontage improvements, including paving, curb and gutter, landscaping, and sidewalks exist along the project site's NE 24th Street frontage. A street modification request was submitted with the short plat application to allow the existing frontage improvements to remain. Sensitive slopes (slopes with grades between 25 percent and 40 percent) and a high landslide hazard area are mapped on the project site. The existing ground surface generally slopes to the northwest with an elevation change of approximately 30 feet. A total of 7 significant trees have been identified on the project site and of these trees, 2 are proposed to be retained. The trees proposed for retention are located on the southwest corner of Lot 1 and the southeast corner of Lot 2. 2. Environmental Review Except when located on lands covered by water or sensitive areas, short plats are exempt from SEPA Environmental Review pursuant to WAC 197-11-800(6)(a). 3_ Compliance with ERC Conditions N/A 4. Staff Review Comments Representatives from various city departments have reviewed the application materials to identify and ;id dress issues raised by the proposed development. These comments are contained in the official file, and the essence of the comments have been incorporated into the appropriate sections of this report and the Departmental Recommendation at the end of this report. 4. Consistency with Short Plat Criteria SHORT PLAT REVIEW CRITERIA: Approval of a short plat is based upon several factors. The following short plat criteria have been established to assist decision-makers in the review of the plat. (" Compliant; Note 1: Partially compliant; Note 2: Not compliant; Note 3: Compliance not yet demonstrated) r:;1-1P1 Ponrvt 1,1.nnu~c::11 ,,, City of Renton Depo11ment of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Sho/1 Plat Report & Decision WA14-001654, SHPL-A Report of March 6, 2015 Page 5 of 21 1. CONFORMANCE WITH THE COMPREHENSIVE PLAN: The site has the Comprehensive Land Use designation of Residential Single Family (RSF). Land designated RSF is intended to be used for high quality detached, single-family residential development organized into neighborhoods at urban densities. It is intended that larger subdivisions, infill development, and rehabilitation of existing housing be carefully designed to enhance and improve the quality of single family living environments. The proposal is consistent with the following Comprehensive Plan Land Use and Community Design Element policies, if all conditions of approval are met, unless noted otherwise: "' Policy LU-158. Net development densities should fall within a range of 4.0 to 8.0 dwelling units per acre in Residential Single Family Neighborhoods. "' Policy CD-14. Infill development, defined as new short plats of nine or fewer lots, should be encouraged in order to add variety, updated housing stock, and new vitality to neighborhoods. "' Policy CD-15. Infill development should be reflective of the existing character of established neighborhoods even when designed using different architectural styles, and/or responding to more urban setbacks, height or lot requirements. Infill development should draw on elements of existing development such as placement of structures, vegetation, and location of entries and walkways, to reflect the site planning and scale of existing areas. 2. COMPLIANCE WITH THE UNDERLYING ZONING DESIGNATION: Objectives and policies of the Comprehensive Land Use Plan RSF designation are implemented by Residential 8 zoning (R-8). RMC 4-2-llOA provides development standards for development within the R-8 zoning classification. The proposal is consistent with the following development standards if all conditions of approval are met, unless noted otherwise: "' Density: The allowed density range in the R-8 zone is a minimum of 4.0 to a maximum of 8.0 dwelling units per acre. Net density is calculated after the deduction of sensitive areas, areas intended for public right-of-way, and private access easements. Staff Comment: For the purposes of calculating net density the 1,763 square foot private access easement is required to be deducted from the gross site area of 25,400 square feet, resulting in a net area of 23,637 square feet (0.54 acres). Based on the proposal for 3 lots, the net density would be 5.6 dwelling units per net acre, which is within the allowed density range for the R-8 zone. "' Lot Dimensions: Proposed Lots Lot Size Width Depth 7,000 SF minimum 60 feet minimum 90 feet minimum (70 feet for corner lots) Lot 1 7,023 sf 71.50 feet 99.24 feet lot 2 7,004 sf 91.12 feet 96.24 feet Lot 3 9,610 sf 60.00 feet 162.62 feet Note 3 Setbacks: The required setbacks in the R-8 zone per the Interim Zoning Ordinance 5724 are as follows: front yard is 25 feet, side yard (or shared driveway) is 7.5 feet, side yard SHPL Report 14-001654 v2 City of Renton Deportment of Community & Economic Development Nf 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Page 6 of 21 along the street or access easement is 17.5 feet and the rear yard is 25 feet. Staff Comment: A 16-foot wide private access easement is proposed along the eastern side of Lot 2 to provide access to Lot 3. The front yard areas of proposed Lots 1 and 2 would be oriented to the south towards NE 24th Street; the front yard of Lot 3 would be oriented to the east. As proposed the new lots would provide adequate area for compliance with the required setbacks. Setbacks would be verified at the time of building permit review. Note 3 Building Standards: The Interim R-8 zoning requirements, per Ordinance 5724, for maximum building height is 30 feet. The maximum building coverage is 40 percent. Staff Comment: Building height and lot coverage for the new single family residences would be verified at the time of building permit review. Note 1 Landscaping: The City's landscape regulations (RMC 4-4-070) require all short plats to provide a 10-foot landscape strip along all public street frontages. Additional 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, ground cover, are to be located in this area when present. Spacing standards shall be as stipulated by the Department of Community and Economic Development, provided . there shall be a minimum of one street tree planted per address. Any additional undeveloped right-of-way areas shall be landscaped unless otherwise determined by the Administrator. Where there is insufficient right-of-way space or no public frontage, street trees are required in the front yard subject to approval of the Administrator. A minimum of two trees are to be located in the front yard prior to final inspection. Staff Comment: A conceptual landscape pion (Exhibit A.SJ was submitted as part of the proposed land use application. The conceptual landscape plan (Exhibit A.SJ shows a 10- foot wide landscaped strip along NE 24 11' Street. A planting detail was included showing 3 Western Red Cedar trees, 5 Vine Maple trees, Dayli/ies, Hansa Japanese Rose, Sword Fern, Pacific Wax Myrtle, Variegated Dogwood, Dwarf Mugo Pine, Maiden Grass, and Kinnickinnick. A street modification request {Exhibit A.10) was submitted with the short plat application allowing the applicant to retain the existing 6.5-foot landscape strip between the curb and sidewalk. The existing 6.5-foot landscape strip has 4 street trees. Due to the proposed locations af the driveways for the new lots, the applicant is proposing to replace or relocate 3 of the existing street trees (one tree would remain in its current location}. If the driveway curb cut for Lot 2 was consolidated with the proposed access easement to the west (providing access to Lot 3) only 1 existing street tree would need to be relocated or replaced (see further discussion below under access}. To ensure retention of the existing mature street trees, staff recommends a condition of approval that a minimum of two existing street trees are retained. No trees were proposed within the front yard area of new Lot 3. Staff recommends, as a condition of approva, that a detailed landscape plan be submitted at the time of Construction Permit application for review and approval by the Current Planning Project Manager. The detailed landscape plan shall include two trees within the front yard area of Lot 3 and show the relocation or replacement of one street tree along NE 24th Street. SHPL Rennrt 14-nntfi~Ll. 1,J City of Renton Department of Community & Economic Development NE 24TH STREfT SHORT PLAT Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Report of March 6, 2015 Page 7 of 21 The 10-foot landscaped strip and street trees shall be installed prior to final short plat approval and the street/front yard trees shall be installed prior ta final building inspection. ./ Tree Retention: The City's adopted Tree Retention and land Clearing Regulations require the retention of 30 percent of trees in a residential development. Staff Comment: A Tree Cutting/land Clearing Plan (Exhibit A.6} and o Tree Retention Worksheet (Exhibit A.7) were submitted with the short plat application materials. There are a total of 7 significant trees located on the project site. A total of 2 trees are proposed ta be retained. To comply with the Tree Retention requirements, 2 trees are required to be retained or replaced. The proposal to retain 2 trees would comply with this requirement. Staff recommends as a condition of approval that o final Tree Retention pion in compliance with the City's adapted Tree Retention and land Clearing Regulations be submitted at the time of Construction Permit application for review and approval by the Current Planning Project Manager. Note 3 Parking: Parking regulations require that a minimum of two parking spaces be provided for each detached dwelling. ,/ Driveway cuts are required to be a minimum of 5 feet from property lines and new driveways may be a maximum of 16 feet in width at the property line. Staff Comment: As proposed, each lot would hove adequate area to provide two off- street parking spaces. Compliance with the parking requirements would be verified at the time of building permit review. Compliance with driveway standards would be verified at the time of building permit review. Critical Areas: A high landslide hazard area and sensitive slopes (with a grade between 25 and 40 percent) are mapped on the project site. High landslide hazard areas and sensitive slopes are regulated under the City's Critical Areas Regulations (RMC 4-3-050). Staff Comment: A Geotechnical Engineering Report prepared by GeoResources, LLC, dated December 22, 2014 (Exhibit A.8} was submitted with the project application. According to the report the slopes on the project site range from 13 to 15 percent and are underlain with Indianola Loamy Sand. As the onsite slopes have grades less than 25 percent, the report {Exhibit A.BJ concludes that they would not meet the definition of sensitive slopes per the City's Critical Areas Regulations {RMC 4-3-050). In addition, the report also concludes that the presence of sandy soils onsite with grades between 13 to 15 percent do not meet the criteria for a high landslide hazard area and would instead meet the criteria for a low landslide hazard area. The report included recommendations for site preparation and grading, structural fill, foundation support, and floor slab support. Stoff recommends as a condition of approval that project construction be required to comply with the recommendations provided in the Geotechnical Engineering Report prepared by GeoResources, LLC, dated December 22, 2014. 3. DESIGN STANDARDS: Residential Design and Open Space Standards (RMC 4-2-115) are applicable in the R-8 zone. The Standards implement policies established in the land Use and Community Design Elements of the Comprehensive Plan. Compliance with Site Design Standards must be demonstrated prior to approval of the subdivision. Compliance with Residential Design SHPL Report 14-001654 v2 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Report of March 6, 2015 Page 8 of 21 Standards would be verified prior to issuance of building permits. The proposal is consistent with the following design standards, unless noted otherwise: ./ Lot Configuration: One of the following is required: 1. Lot width variation of 10 feet (10') minimum of one per four (4) abutting street-fronting lots, or 2. Minimum of four (4) lot sizes {minimum of four hundred (400) gross square feet size difference), or 3. A front yard setback variation of at least five feet {5') minimum for at least every four (4) abutting street fronting lots. Staff Comment: As proposed the short plat would comply with requirement number 1. Proposed Lot 1 would have a lot width af 71.50 feet and Lot 2 would have a lot width of 91.12/eet. The difference in width between the street fronting lots (Lots 1 and 2) would exceed 10 feet. Note 3 Garages: One of the following is required; the garage is: 1. Recessed from the front of the house and/or front porch at least eight feet (8'), or 2. Located so that the roof extends at least five feet (5') (not including eaves) beyond the front of the garage for at least the width ofthe garage plus the porch/stoop area, or 3. Alley accessed, or 4. Located so that the entry does not face a public and/or private street or an access easement, or 5. Sized so that it represents no greater than fifty percent (50%) ofthe width of the front facade at ground level, or 6. Detached. The portion of the garage wider than twenty six-feet (26') across the front shall be set back at least two feet (2'). Staff Comment: Compliance for this standard would be verified at the time of building permit review. Note 3 Primary Entry: One of the following is required: 1. Stoop: minimum size four feet by six feet (4' x 6') and minimum height twelve inches (12") above grade, or 2. Porch: minimum size five feet {5') deep and minimum height twelve inches (12") above grade. Exception: in cases where accessibility (ADA) is a priority, an accessible route may be taken from a front driveway. Staff Comment: Lot 2 shall be required to provide vehicular access to the home from the access easement. However, it should be noted that the primary entry of the home should face NE 24'h Street. Ta ensure the home maintains this orientation, staff recommends a condition of approval, that the primary entry features be located on the far;ade facing NE City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Report of March 6, 2015 Page 9 of 21 241h Street. Compliance for this standard would be verified at the time of building permit review. Note3 Fa~ade Modulation: One of the following is required: 1. An offset of at least one story that is at least ten feet (10') wide and two feet (2') in depth on facades visible from the street, or 2. At least two feet (2') offset of second story from first story on one street facing facade. Staff Comment: Compliance for this standard would be verified at the time of building permit review. Note 3 Windows and Doors: Windows and doors shall constitute twenty-five percent (25%) of all facades facing street frontage or public spaces. Staff Comment: Lot 2 shall be required to provide vehicular access to the home from the access easement. However, it should be noted that the windows and doors of the home should face NE z4th Street. To ensure the home maintains this orientation, staff recommends a condition of approval, that the windows and doors features be located on the f01;:ade facing NE z4'h Street. Compliance for this standard would be verified at the time of building permit review. N/A Scale, Bulk, and Character: N/ A Note3 Roofs: One of the following is required for all development: 1. Hip or gabled with at least a six to twelve (6:12) pitch for the prominent form of the roof (dormers, etc., may have lesser pitch), or 2. Shed roof. Additionally, for subdivisions greater than nine (9) lots: A variety of roof forms appropriate to the style of the home shall be used. Staff Comment: Compliance for this standard would be verified at the time of building permit review. Note 3 Eaves: Both of the following are required: 1. Eaves projecting from the roof of the entire building at least twelve inches (12") with horizontal fascia or fascia gutter at least five inches (S") deep on the face of all eaves, and 2. Rakes on gable ends must extend a minimum of two inches (2") from the surface of exterior siding materials. Staff Comment: Compliance for this standard would be verified at the time of building permit review. Note 3 Architectural Detailing: If one siding material is used on any side of the dwelling that is two stories or greater in height, a horizontal band that measures at least eight inches (8") is required between the first and second story. Additionally, one of the following is required: 1. Three and one half inch (3 1/2") minimum trim surrounds all windows and SHPL Report 14-001654 v2 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision lUA14-001654, SHPL-A Report of March 6, 2015 Page 10 of 21 details all doors, or 2. A combination of shutters and three and one half inches (3 1/2") minimum trim details all windows, and three and one half inches (31/2") minimum trim details all doors. Staff Comment: Compliance for this standard would be verified at the time of building permit review. Note 3 Materials and Color: For subdivisions and short plats, abutting homes shall be of differing color. Color palettes for all new dwellings, coded to the home elevations, shall be submitted for approval. Additionally, one of the following is required: 1. A minimum of two (2) colors is used on the home (body with different color trim is acceptable), or 2. A minimum of two (2) differing siding materials (horizontal siding and shingles, siding and masonry or masonry-like material, etc.) is used on the home. One alternative siding material must comprise a minimum of thirty percent (30%) of the street facing facade. If masonry siding is used, it shall wrap the corners no less than twenty four inches (24"). Staff Comment: Compliance for this standard would be verified at the time of building permit review. 4. COMPLIANCE WITH SUBDIVISION REGULATIONS: RMC 4-7 Provides review criteria for proposed subdivisions. The proposed project is consistent with the following subdivision regulations if all conditions of approval are complied with: Note 1 Access: Alley access is the preferred street pattern in the R-8 zone, unless the development proposed is a short plat. As the proposed project is a short plat, it is exempt from the alley access requirements. There are two existing curb cuts, one is located on the southeast corner of Lot 1 and the other is located on the southwest corner of Lot 2. As part of the proposed short plat, the locations of the curb cuts are proposed to be relocated. Staff recommends, as a condition of approval, that the unused curb cuts be removed and replaced with curb and gutter, landscaping, and sidewalk. Revised frontage improvement plans showing the removal ofthe unused curb cuts and the replacement with curb and gutter, landscaping, and sidewalk shall be submitted at the time of Utility Construction Permit review for review and approval by the City's Plan Reviewer. Installation of the improvements shall be completed prior to final short plat approval. Access to Lots 1 and 2 is proposed via residential driveways off of NE 24'h Street. Access to proposed Lot 3 would be provided via a new 18-foot wide private access easement located along the eastern portion of proposed Lot 2 with 16 feet of pavement. Per RMC 4-4-0801. 7.a joint use driveways should be encouraged to reduce the number of curb cuts along public street frontages, therefore, Lot 2 should also be required to take access off of the proposed access easement. Staff recommends as a condition of approval that access to Lot 2 be provided via the proposed access easement on the eastern portion of Lot 2. A note requiring the access to Lot 2 to be provided from the access easement shall SHPL RPnnrt 14-nnu:.;r:::;4 11) City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plot Report & Decision LUA14-001654, SHPL-A Report of March 6, 2015 Page 11 of 21 " " be recorded on the face of the final short plat map. A shared private driveway may be permitted for access up to a maximum of four (4) lots. Up to three (3) of the lots may use the driveway as primary access for emergencies. The private access easement shall be a minimum width of 16 feet with a maximum of 12 feet paved driveway, unless 20 feet is required by the Fire Department for emergency access. The applicant submitted a variance request to the Fire Department requesting a reduction in the 20-foot emergency access pavement requirement down to 16 feet with a fire sprinkler system to be installed within the future residence on Lot 3. The Fire Department has reviewed the requested variance and has approved the reduction in pavement width from 20 feet to 16 feet subject to the condition that the future residence on Lot 3 be equipped with a fire sprinkler system. Staff recommends as a condition of approval that a note be recorded on the final short plat map stating that the future residence to be constructed on Lot 3 shall be equipped with a fire sprinkler system. The minimum separation of access from the adjacent property line is five feet. The proposed access as shown in the plans provides the required five feet separation. Streets: NE 24th Street fronting the proposed project site is classified as a residential access street and has an existin_g right-of-way width of 57 feet. Per the street standards (RMC 4-6-060), the minimum right-of-way width required on a residential access street is 53 feet with 26 feet of paving, 0.5-foot curb, 8-foot landscape planter, 5-foot sidewalk, and street lighting. The existing right-of-way width is adequate, no additional dedication is required. Frontage improvements including paving, curb and gutter, 6.5-foot landscape strip, and sidewalk exist along the project frontage. The applicant submitted a modification to the street standards to allow the existing frontage improvements to remain. The requested Modification complies with the criteria outlined in RMC 4-9-250D per the approval letter dated February 12, 2015 (Exhibit A.11). Blocks: No new blocks would be created as a result of the proposed subdivision. The proposed short plat would be consistent with development patterns in the surrounding area. Lots: The size, shape, orientation, and arrangement of the proposed lots comply with the requirements of the Subdivision Regulations and the Development Standards of the R-8 zone, interim zoning standards (Ord. 5724) and allow for reasonable infill of developable land. All of the proposed lots meet the requirements for minimum Jot size, depth, and width. All of the proposed lots are rectangular in shape. The front yard areas of Lots 1 and 2 would be oriented to the south toward NE 24th Street and the front yard of Lot 3 would be oriented to the east. Note 1 Topography and Vegetation: Sensitive slopes (with grades between 25 and 40 percent) and a high landslide hazard area are mapped on the project site, According to the submitted Geotechnical Engineering Report (Exhibit A.SJ, the existing ground surface generally slopes to the northwest with grades ranging from 13 to 15 percent. The submitted geotechnical report concludes that the onsite slopes and soil conditions would not meet the criteria for sensitive slopes and high landslide areas. A total of seven SHPL Report 14-001654 v2 Cily of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plot Report & Decision LUA14-001654, SHPL-A Page 12 of 21 significant trees have been identified on the project site and of these trees two are proposed to be retained. See previous discussion above under Tree Retention, and Critical Areas. 5. AVAILABILITY AND IMPACT ON PUBLIC SERVICES: Police: Police staff indicates that there would be minimal impact on police services as a result of the proposed subdivision and sufficient resources exist to furnish services to the proposed development. Fire: The fire flow requirement for a single family home is 1,000 gpm minimum for dwellings up to 3,600 square feet (including garage and basements). If the dwelling exceeds 3,600 square feet, a minimum of 1,500 gpm fire flow would be required. A minimum of one fire hydrant is required within 300-feet of the proposed buildings and two hydrants if the fire flow goes up to 1,500 gpm. It appears there is adequate fire flow in this area. There is an existing hydrant fronting the project site, which can deliver 1,000 gpm. Fire department apparatus access roadways are required to be minimum 20-feet wide fully paved. Fire access roadways shall be constructed to support a 30-ton vehicle with 322-psi point loading. Access is required within 150-feet of all points on the buildings. A 20-foot paved emergency access would be required to service proposed Lot 3. The applicant has requested a variance to the 20-foot pavement width requirement. The applicant is proposing a 16-foot paved driveway and the installation of a fire sprinkler system within the future residence to be constructed on new Lot 3. The Fire Department has approved the variance request. See previous discussion above under Access. A Fire Impact Fee for the future houses would be payable at the time of building permit issuance. The current Fire Impact Fee is $479.28; the fee in effect at the time of building permit application would be applied to this project. Schools: The Renton School District has indicated that it can accommodate the impact of additional students expected to come from the proposed project at Kennydale Elementary School, McKnight Middle School, and Hazen High School. Students attending Kennydale Elementary would walk to school heading west along the existing sidewalk on the north side of NE 24th Street to Jones Avenue NE where they would turn north and walk along the existing sidewalk along the east side of Jones to school. Students attending McKnight Middle School would walk to the east along the existing sidewalk on the north side of NE 24th Street to Edmonds Avenue NE where they would turn south and walk along the existing sidewalk to McKnight Middle School. Students attending Hazen High School would be bussed to school from the existing stop located approximately 0.09 miles to the east at the intersection of NE 24th Street and Aberdeen Avenue NE. To get to this bus stop, students would walk to the east along the existing sidewalk along NE 24th Street. The current Renton School District Impact Fee is $5,541.00. The Renton School Impact Fee would be payable at the time of building permit issuance; the fee in effect at the time of building permit application would be applied to this project. City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Page 13 of 21 ,/ Parks: A Park Impact Fee would be required for the future houses. The current Park Impact Fee is $1,441.29. The fee in effect at the time of building permit application is applicable to this project and is payable at the time of building permit issuance. Note 3 Stormwater: A Preliminary Technical Information Report (TIR) prepared by Encompass Engineering and Surveying (Exhibit A.9) and a geotechnical report prepared by GeoResources LLC (Exhibit A.8) were submitted with the project application. The geotech report (Exhibit A.8) states that the onsite soils are medium sand and are suitable for infiltration of stormwater. The submitted TIR (Exhibit A.9) states that the existing surface water runoff infiltrates into the existing soils. Runoff that does not infiltrate would sheet flow to the northwest onto the adjacent property and eventually into a biofiltration swale located 70 feet to the northwest of the project site. Surface flows continue through the swale and enters a piped storm system, which eventually discharges to Kennydale Creek and continues on to the 1-405 storm system. No drainage problems were identified. Infiltration trenches are proposed onsite to control surface water runoff generated by the proposed development. Infiltration trenches must be setback at least 15 feet from buildings with crawl space or basement. Runoff from roadways, driveways, and parking areas shall pass through a yard drain or catch basin fitted with a down-turned elbow, prior to entering the infiltration trench (see Figure c'..2.2.B, p. C46). The elbow is intended to trap spilled material in the catch basin sump so that the spilled material can be cleaned up more easily by the homeowner. The preliminary grading plans (Exhibit A.4) show fill on a portion of the infiltration facilities. Having tractors or dozers go over these areas decreases their infiltration rate. Staff recommends, as a condition of approval, that no fill be allowed within the natural infiltration areas and compaction of the proposed infiltration areas shall not be permitted. An additional infiltration rate test will be required using the falling head permeability test for each infiltration area on each lot. There currently is not a rate provided in the submitted geotechnical report (Exhibit A.8). An additional pit test is required for Lot 3's infiltration area. These infiltration areas are very important because they are proposing full infiltration. Infiltration is not allowed for slopes greater than 15%. Lot 3's test pit exploration should be conducted at the lowest elevation which is near the property line. The depth of exploration should be a minimum of 6 feet. Presence of high ground water in the testing, by a geotechnical engineer, may require additional mitigation elements, including storage and pumping during the construction utility review process. The special requirement #6 regarding Aquifer Protection Area should be included in the drainage report submitted with the utility construction permit. The site falls in the Aquifer Protection Area zone 2. Drainage plans and a final drainage report based on the City adopted 2009 Surface Water Design Manual Amendment and the 2009 King County Surface Water Drainage is required to be submitted with the Construction permit. All stormwater requirements as per the 2009 Surface Water Design Manual Amendment and the 2009 King County Surface Water Drainage Manual is required to be provided by the project. Surface water system development fee is $1,350.00 per new lot. Fees are payable prior to issuance of the construction permit. SHPL Report 14-001654 v2 City of Renton Deportment of Community & Economic Development Nf 24TH STRffT SHORT PLAT Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Report of March 6, 2015 Page 14 of 21 / Water Service: The proposed development is within the City's water service area and in the Highlands 435-hydraulic zone. There is an existing 12-inch water main (see City water project plan no. W-1134) in NE 24th St. The 12-inch line can deliver 3,600 gallons per minute (gpm). The static water pressure is about 58 psi at elevation of 300 feet. There is an existing fire hydrant in front the property which can deliver 1,000 gallons per minute. The proposal will be required to install a 1-inch minimum domestic water service line and meter to each lot and may be required to install an additional fire hydrant within 300 feet of each lot, if required by Renton Fire Prevention Department for single family dwelling exceeding 3,600 sq. ft. of gross area. A redevelopment credit is applicable to an abandoned 3/4-inch meter that used to serve a house at 1908 NE 24th St that has been demolished in 2011. The development is subject to the water system development charge of$ 3,090.00 for the proposed lots. These fees are collected at the time a construction permit is issued and the rate prevalent at time of construction permit will be applicable. / Sanitary Sewer Service: The site is located in the city of Renton sewer service area. There is an 8-inch sewer main in NE 24TH Street. There are two existing sewer stubs for two existing lots. A 6-inch sewer extension from the existing 8-inch main at NE 24TH Street is required to provide access to proposed Lot 3. The development is subject to a wastewater system development charge (SOC) fee. The SOC fee for sewer is based on the size of the new domestic water to serve the new home on each lot. The sewer fee for a %-inch or 1-inch meter install is $2,135.00. The applicant is required to pay SDC fee for existing and proposed lots. The West Kennydale Interceptor Special Assessment District fee {SAD) will be applicable on this project. The SAD fee would be $1,050.00 per lot. / Transportation: See previous discussion above under Access and Streets. A Transportation Impact Fee for the new houses would be payable at the time of building permit issuance; the fee in effect at the time of building permit application would be applied to this project. The Transportation Impact Fee is $2,214.44. H. FINDINGS: Having reviewed the written record in the matter, the City now enters the following: 1. Request: The applicant is requesting approval of a 3-lot short plat on a 25,400 square foot site. The project would have a net density of 5.6 dwelling units per acre. 2. Application: The subject property is located at 1904 and 1908 NE 24th Street. 3. Comprehensive Pian: The subject property is designated as Residential Single Family (RSF) in the Comprehensive Plan. The proposed project would satisfy the objectives and policies of the Land Use and Community Design of the Comprehensive Plan, if all conditions are complied with. 4. Zoning: The proposed project site is zoned Residential -8 dwelling units per net acre {R-8) and is subject to the interim zoning standards as adopted under Ordinance 5724. The project City of Renton Deportment of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Sho1t Plot Report & OeC,:sion LUA14-001654, SHPL-A Page 15 of 21 as proposed would satisfy the R-8 standards and regulations as well as the interim zoning standards, if all conditions are complied with. 5. Subdivision Regulations: The project as proposed would satisfy the requirements of RMC 4-7, Subdivision Regulations if all conditions are complied with. 6. Existing Land Uses: The subject property is currently vacant. 7. Setbacks: Building setbacks for the future houses on the new lots would be verified at the time of building permit review. 8. System Development Charges: The surface water service development fee is $1,350.00 per single-family lot. System development fee (SDC) for sewer is based on the size of the new domestic water to serve the houses on each lot. Sewer SOC fee for %-inch or 1-inch meter install is $2,135.00. Water SOC fee for %-inch or 1-inch meter install is $3,090.00. 9. Public Services: The proposed short plat has been reviewed by various City Departments. There are adequate public services and facilities to accommodate the proposed short plat. Transportation, Fire, and Park Impact fees are applicable for the future houses on the new lots. Impact fees are assessed at the time of building permit application and are payable at the time of building permit issuance. 10. Public Utilities: Water, sewer, and storm drainage would be provided by the City of Renton. 11. Schools: The Renton School District has indicated that adequate school facilities are available at Kennydale Elementary, McKnight Middle, and Hazen High Schools. A Renton School District Impact Fee would be assessed at the time of building permit application and would be payable at the time of building permit issuance. 12. Safe Routes to Schools: Students would walk to Kennydale Elementary and McKnight Middle Schools. Renton School District bus service is available to Hazen High School. There are safe walking routes to Kennydale Elementary and McKnight Middle schools as well as to the existing bus stop located at NE 24th Street and Aberdeen Avenue NE. 13. Topography/Critical Areas: Sensitive Slopes (slopes with grades between 25 and 40 percent), a high landslide hazard area, and Aquifer Protection Area 2 are mapped on the project site. According to the submitted geotech report (Exhibit A.8), the existing ground surface generally slopes to the northwest with grades ranging between 13 and 15 percent. According to the geotech report the onsite slopes do not meet the City's criteria for Sensitive Slopes or High Landslide Hazard Areas, and instead should be classified as Low Landslide Hazard Areas as they meet the Low Landslide Hazard Area criteria. I. CONCLUSIONS: 1. The subject site is located in the Residential Single Family Comprehensive Plan designation and complies with the goals and policies established with this designation. 2. The subject site is located in the Residential -8 dwelling units per acre (R-8) zoning designation and is subject to interim zoning adopted under Ordinance 5724 and complies with the zoning and development standards established with these designations provided the applicant complies with City Code and conditions of approval. SHPL Report 14-001654 v2 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plat Report & Decision WA14-001654, SHPL-A Page 16 of 21 3. The proposed 3-lot short plat complies with the subdivision regulations as established by City Code and state law provided all advisory notes and conditions are complied with. 4. The proposed 3-lot short plat complies with the street standards, as established by City Code, provided the project complies with all advisory notes and conditions of approval contained herein. 5. Slopes with grades between 15 and 25 percent and a medium landslide hazard area are mapped on the project site. Sensitive Slopes (slopes with grades between 25 and 40 percent), a high landslide hazard area, and Aquifer Protection Area 2 are mapped on the project site. According to the submitted geotech report (Exhibit A.8), the existing ground surface generally slopes to the northwest with grades ranging between 13 and 15 percent. According to the geotech report the onsite slopes do not meet the City's criteria for Sensitive Slopes or High Landslide Hazard Areas, and instead should be classified as Low Landslide Hazard Areas as they meet the Low Landslide Hazard Area criteria. The proposed 3-lot short plat complies with the critical areas regulations as established by City Code provided the applicant complies with the conditions of approval. 6. There are safe walking routes to the schools and school bus stop. 7. There are adequate public services and facilities to accommodate the proposed short plat. J. DECISION: The NE 24th Street Short Plat and street modification (Exhibit A.11), File No. LUA14-001624, SHPL- A, is approved and is subject to the following conditions: 1. A detailed landscape plan shall be submitted at the time of Construction Permit application for review and approval by the Current Planning Project Manager. The detailed landscape plan shall include, but is not limited to, two trees within the front yard area of Lot 3 and show the relocation or replacement of one street tree along NE 24th Street. The 10-foot landscaped strip shall be installed prior to final short plat recording and the street/front yard trees shall be installed prior to final building occupancy. 2. A final Tree Retention plan in compliance with the City's adopted Tree Retention and land Clearing Regulations shall be submitted at the time of Construction Permit application for review and approval by the Current Planning Project Manager. 3. Project construction shall be required to comply with the recommendations provided in the Geotechnical Engineering Report prepared by GeoResources, LLC, dated December 22, 2014. 4. Revised frontage improvement plans showing the removal of the unused curb cuts and the replacement with curb and gutter, landscaping, and sidewalk shall be submitted at the time of Utility Construction Permit review for review and approval by the City's Plan Reviewer. Installation of the improvements shall be completed prior to final short plat approval. 5. Access to Lot 2 shall be provided via the proposed access easement on the eastern portion of Lot 2. A note requiring the access to lot 2 to be provided from the access easement shall be recorded on the face of the final short plat map. 6. A fire sprinkler system shall be required within the future residence to be constructed on new Lot 3. A note to this effect shall be recorded on the final short plat map. City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Page 17of21 7. No fill shall be allowed within the natural infiltration areas and compaction of the proposed infiltration areas shall not be permitted. 8. A minimum of two existing mature street trees shall be retained. The updated tree retention plan identifying retention of two street trees shall be submitted at the time of Construction Permit application for review and approval by the Current Planning Project Manager. 9. Primary entry features and windows and doors shall be located on the fa~ade facing NE 241 h St. Compliance with these standards shall be show on the building permit application for Lot 2. DATE OF DECISION ON LAND USE ACTION: SIGNATURE: Jennifer Henning, Planning.,Director TRANSMITTED this 5th day af March, 2015 to the Owner/Applicant/Contact: Owner: John Cowan 1830 NE 24'' Street Renton, WA 98056 Applicant: Bill Hughes 14404 Issaquah-Hobart Road Issaquah, WA 98027 TRANSMITTED this 5th day of March, 2015 to the Parties of Record: Polly And Carl Brooks 2414 Kennewick Place NE Renton, WA 98056 Matthew and Patti Mark 2420 Kennewick Place NE Renton, WA 98056 Steve and Veronica Dink;ns 2413 Kennewick Place NE Renton, WA 98056 Robert Du Wars 2508 Kennewick Place NE Renton, WA 98056 TRANSMITTED this s'" day of March, 2015 to the following: Jennifer Henning, Planning Director Steve Lee, Development Engineering Manager Jan Conklin, Development Services Vanessa Dolbee, Current Planning Manager Fire Marshal SHPL Repo1t 14-00.1654 v2 3/r,,/20;5 Date Contact: Tom Redding Encompass Engineering & Surveying 165 NE Juniper Street, Suite 201 Issaquah, WA 98027 James Dixon 2517 Kennewick Avenue NE Renton, WA 98056 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plot Report & Decision lUAl4-00l654, SHPL-A Page 18 of 21 /(. LAND USE ACTION APPEALS, REQUEST FOR RECONSIDERATION, & EXP/RATION: The administrative land use decision will become final if the decision is not appealed within 14 days of the decision date. APPEAL: This administrative land use decision will become final if not appealed in writing to the Hearing Examiner on or before 5:00 PM on March 20, 2015. An appeal of the decision must be filed within the 14-day appeal period (RCW 43.21.C.075(3); WAC 197-11-680), together with the required fee to the Hearing Examiner, City of Renton, 1055 South Grady Way, Renton, WA 98057. RMC 4-8- 110.B governs appeals to the Hearing Examiner and additional information regarding the appeal process may be obtained from the City Clerk's Office, (425) 430-6510. EXPIRATION: The administrative short plat decision will expire two (2) years from the date of decision. A single one (1) year extension may be requested pursuant to RMC 4-7-070.M. RECONSIDERATION: Within 14 days of the decision date, any party may request that the decision be reopened by the approval body. The approval body may modify his decision if material evidence, not readily discoverable prior to the original decision, is found or if he finds there was misrepresentation of fact. After review of the reconsideration request, if the approval body finds sufficient evidence to amend the original decision, there will be no further extension of the appeal period. Any person wishing to take further action must file a formal appeal within the 14-day appeal time frame. THE APPEARANCE OF FAIRNESS DOCTRiNE: provides that no ex pa rte (private one-on-one) communications may occur concerning the land use decision. The Doctrine applies not only to the initial decision, but to Appeals to the Hearing Examiner as well. All communications after the decision/approval date must be made in writing through the Hearing Examiner. All communications are public record and this permits all interested parties to know the contents of the communication and would allow them to openly rebut the evidence in writing. Any violation of this doctrine could result in the invalidation of the appeal by the Court. ADVISORY NOTES TO APPLICANT The following notes are supplemental information provided in conjunction with the administrative land use action. Because these notes are provided as information only, they are not subject to the appeal process for the land use actions. Planning: 1. Construction activities shall be restricted to the hours of 7:00 am to 8:00 pm, Monday through Friday. Work on Saturdays shall be between the hours of 9:00 am and 8:00 pm. No work shall be permitted on Sundays. 2. RMC 4-4-030C.2 limits haul hours between the hours of 8:30 am and 3:30 pm, Monday through Friday unless otherwise approved by the Department of Community and Economic Development. Technical Services: 1. Note the City of Renton land use action number and land record number, LUA14-001654 and LND 20 0616, respectively, on the final short plat submittal. The type size used for the land record number should be smaller than that used for the land use action number. 2. Provide short plat and lot closure calculations. 3. Note discrepancies between bearings and distances of record and those measured or calculated, if SN Pl Report 14-001654 v2 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Report of March 6, 2015 Page 19 of 21 any. 4. Note addresses from the attached on the final short plat drawing. 5. Do note encroachments, if any. 6. Do include a "LEGEND" block for the short plat drawing, detailing any symbols used thereon. Include symbols for the 8' wood fence, 5' cyclone fence, 4' wood fence, rockery, etc. 7. Remove the various patterns (dots) noted in the street (NE 24TH STREET), the existing driveway, the existing gated tract road and the proposed 16-foot paved driveway. 8. Remove the building setback lines from all three lots. Setbacks are determined when permits are issued. 9. Remove all references to trees, currently shown on all three lots, from the short plat submittal. 10. Note all easements, covenants and agreements of record on the drawing. 11. Note any relevant researched resources on the short plat submittal. 12. Note that the correct page reference for the plat of Sunset Hills (noted for lots surrounding the subject short plat site on the drawing sheet) is PGS 5155, not "PG 52". 13. Remove the zoning, proposed net density, max allowable density, critical areas and critical areas buffer information and the proposed public street dedication information from the final short plat submittal. Also remove the "PROPERTY OWNER" AND "ENGINEER/SURVEYOR" blocks. 14. Add a north arrow to the "VICINITY MAP". 15. The City of Renton Administrator, Public Works Department, is the only city official who signs the final Short plat submittal. Provide an appropriate approval block and signature line for said administrator. Pertinent King County approval blocks also need to be noted on the submittal. 16. All vested owner(s) of the subject final short plat site need to sign the final short plat drawing. Include notary blocks as needed. 17. Include a declaration block on the drawing, titled "OWNERS' DECLARATION" not "CERTIFICATION" or other. 18. Because the subject property falls within Zone 2 of the City of Renton Aquifer Protection Area, the Aquifer Protection Notice needs to be noted on the drawing. AQUIFER PROTECTION NOTICE The lots created herein fall within Zone 2 of Renton's aquifer protection area and are subject to the requirements of the City of Renton Ordinance #4367. This city's sole source of drinking water is supplied I from a shallow aquifer under the city surface. There is no natural barrier between the water table and ground surface. Extreme care should be exercised when handling of any liquid substance other than water to protect from contact with the ground surface. It is the responsibility of the homeowners to protect the city's drinking water. 19. Note that if there are easements, restrictive covenants or agreements to others (City of Renton, etc.) as part of this subdivision, they can be recorded concurrently with the final short plat. The final short plat drawing and the associated document(s) are to be given to the Project Manager as a package. The recording number(s) for the associated document(s) are to be referenced on the final short plat drawing. Provide spaces for the recording numbers thereof. 20. The new easements for ingress, egress, utilities (private?) and the 5' private sewer easement, shown for the benefit of future owners of proposed Lot 3, each need a note defining the rights associated with the easement at issue. Since these new "proposed" easements shown aren't "granted and conveyed" until the benefited and/or burdened lots are conveyed to others, add the following language on the face of the short plat drawing: SHPL Report 14-001654 vZ City of Renton Deportment of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 DECLARATION OF COVENANT: Administrative Short Plat Report & Decision LUA14-001654, SHPl-A Page 20 of 21 The owners of the land embraced within this short plat, in return for the benefit to accrue from this subdivision, by signing hereon covenant and agree to convey the beneficial interest in the new private easements shown on this short plat to any and all future purchasers of the lots, or of any subdivisions thereof. This covenant shall run with the land as shown on this short plat. The preceding statement obligates the seller of the lots created to "expressly grant and convey" the lots "together with and/or subject to" any new private easements delineated on the short plat in the conveying document. 21. A private ingress, egress and utility easement requires a "New Private Easement for Ingress, Egress and Utilities Maintenance Agreement" statement. 22. The width of the proposed driveway easement changes as it crosses the 10 Utility Easement adjacent to NE 24th Street northern right of way margin but that width is not shown. 23. The easement lines shown along the property line between the two lots don't exist as the lots are excepted from the CC&RS. Water: 1. There is an existing 12-inch water main (see City water project plan no. W-1134) in NE 24th St. The 12-inch line can deliver 3,600 gallons per minute (gpm). 2. The static water pressure is about 58 psi at elevation of 300 feet. 3. There is an existing fire hydrant in front the property which can deliver 1,000 gallons per minute. 4. Separate domestic water meters, minimum 1-inch, are required to serve each single family lot. 5. Installation of an additional fire hydrant within 300 feet of each lot if required by Renton Fire Prevention Department for single family dwelling exceeding 3,600 sq-ft of gross area. 6. Subject to payment of applicable water system development charges and water meter installation fees for the new lots. A redevelopment credit is applicable to an abandoned 3/4-inch meter that used to serve a house at 1908 NE 24th Street that has been demolished in 2011. Sewer: 1. Sewer service is provided by the City of Renton. 2. There is an 8-inch sewer main in NE 24TH Street. 3. There are two existing sewer stubs for two existing lots. 4. Applicant must tap a 6" sewer pipe to 8" main at NE 24TH Street and extend it through the new proposed lot. 5. The building footprint cannot intrude within the sewer easement. Surface Water: 1. Infiltration trenches must be setback at least 15 feet from buildings with crawl space or basement. 2. Runoff from roadways, driveways, and parking areas shall pass through a yard drain or catch basin fitted with a down-turned elbow prior to entering the infiltration trench (see Figure C.2.2.B, p. C46). The elbow is intended to trap spilled material in the catch basin sump so that the spilled material can be cleaned up more easily by the homeowner. 3. Special requirement# 6 Aquifer protection. r-1,n, n~~-~_,_ ~ 1r ,..,,..,..,,,...,, •• , City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 ' Transportation/Streets: Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Page 21 of 21 1. All meter boxes installed in concrete or paved driveways shall be cast iron equal to Olympic Foundary. 2. All electrical, phone, and cable services and lines serving the proposed development must be underground. The construction of these franchise utilities must be inspected and approved by a City of Renton inspector prior to recording the plat. 4. Traffic Impact Fees -Transportation Impact Fee is applicable on single family houses based on the applicable rate at the time of building permit, and payment is due at the time of issuance of the building permit. Fire: 1. The Fire Impact Fees are applicable at the rate of $495.10 per single family unit. This fee is paid at time of building permit. 2. The fire flow requirement for a single family home is 1,000 gpm minimum for dwellings up to 3,600 square feet (including garage and basements). If the dwelling exceeds 3,600 square feet, a minimum of 1,500 gpm fire flow would be required. A minimum of one fire hydrant is required within 300-feet of the proposed buildings and two hydrants if the fire flow goes up to 1,500 gpm. 3. Fire department apparatus access roadway is required to be minimum 20 feet wide fully paved. Applicant has requested a variance to reduce the 20 foot wide roadway to 16 feet on the condition that the home on Lot 3 be equipped with an approved automatic fire sprinkler system. The fire department has no objection to this variance request. SHPL Report 14-001654 v2 ,p' ~ ·., (G .,,-,!!-",'< r?!l725Ui'l31 ,.., )_~_?;: ,,a,u, :1~\!.J ·,-OS-H 1-SHPL i(:"200Dl ij." .>.:! 11.:;. ilENS,i"f411. ,;;;m;;;c,t:;~9 ;~~")DI E42 C 10 .•"J )~ 1; ; -~,n1 :,:;-,5 t11T S ,',~<l• -,~-;g ;.' ':' ,ii,, '--" v,,o ~-- •;"NI~ ,'i1',i} ~.c07 lPL :?:SF {!OOCI~ 11~ SP l\iA-11 'J.l6-'~l"'L ,tt·;r;~'-"\i'Jil'JO.< " r .ITT ":>) 'ii" .·,,:-67 ' .cn,1 l~l. H ·:111 ~~ ~;~o " _.; ... '>I I ·,'llO C·:' 1 12 a ;L0f I; LOTl ~:I! ,it ,'<'- ,· ;;~f;1l I' .,-,.,1 GLllJ -.-,, ~ ------.. -- ! r--.---...-~~'"'. ' w z, '" ~~ ,. l ~;~s~.~ ·1 /hC c:•,.o, ., ri-ii--;Q i ' ,, Ri1.~P L'..! l<Jl J()!,l& 01..'l{}.:,.,\1.!Pl ?{l(,(JD15 ( '-'>l ~'lUf ~ 20!1 • .;)1 j l.'J_1 'l l.li" ,,,,;-;,.,. ·so ~1 RN p L'U,\G·, ~:i \,~IF '\ . 1~9!))5 lOT: ,':°Lor 2 -;; ;' -i~J.; " ·~·: ' ::~?,. ,;95~ :wr3 l-..:;;;::.~..:::..:;1-..:::;:.-1/u. ir-u,• ')~. ~ii LOr S ~ ~'2:\tf; i 0 :; ,~," .• j :!<.'<'''I Ls;,;,:, ,,. '. ,,:o "'~ ;;,'!--- ,.)1 'J. I I . \ i ~ ·~ • • 0 ~ij 2. w !~ '·" ''=I • Exhibit A.3 §' .'!\~ •• :~ •• ;I;~ :~J:! ~! ,1,> s lo ,. f,~·~~ ·~:~·: ' . Exhibit A.4 ~--,.~~.,..-'~.n''~~@ ,.,.,,,,., r _,,.,. "~ •'-' ,,.,...,,. ''! ~:; 11, ;i:.' ·' }~ ,, ;; T !l D N'l1d ,Ul111n/3!) ltNIVHa ll91.0091.fl llWH3d lt/ld l~OHS 101-e HlPl 3N ~ m1 i ! nil "• 11 I! ,. 1!, ,. !;' §e~ ,,.,,.S,W<,""-'<l• '"0,;',~""'!1'1•""""''"''~i~J< .._., ... .._.,,.., ,, ,:n~,-•,,,.·cs •!» ._ .• °'""' ~ ,.,,,.... ·""''" ,...,,,.,~, "'" ~-.. -~ sseal.Uo'5U'3 ' ' I I I I j l I j I I I :~ I i ' r:1 i :,~ i •l'. j l ;'.j , ' 'L~ .H ' ',-- ':i ;-· ( ,, £ , ·,1 __ , ___ ,f'J~-- ,. '~ '· ·~ .- ' ,,; !) ',.1 • q ' :·~-r _; : /, ,1. :·('' ..._____, ___ _ I , i i ,,; :·n, ;j >• ! _j .·l,t '7 ','. 'if , >! I \: is I !. ;fill i') 'i i> ---~------. -----·-· -· f"' i,,,,: " >' I,, 't 1. ;/ :;: ),v,:_,, ,i I i" : ! • 1 i f- t;j . ,:r - V ,.1 J .::: I < ,j ,.i j !, ;; ,j i ' ··, l Exhil;iit AlS ',C I ~! ::, ' 5H I u (/) >-z :5 a. ,: z :I: ' I I ,I ' \ \ I \ \ \ \ \ ·--·u· ... ."s: lllltlOO-tl1lid Y.-'I\ "J\.0.L.\I]~ ,\101SL\!UHilS .U!Of-!S .LT-1~.LS ! LI.vi: :-l:,,j ,_-- 1 \ \ \ \ \ c-g X 0,...., _J 8- X _ __...r )( l .\lVld c!dV::>SGNV"l II ·!'' 'Ii. ;'.d; ... ,<(,:~~_,;"08 <!, ?)tI •;--. •·- ! •• \: .-¢:~ ' ~, ' 2 - lu w ~ ~ ,,. N • s ; ~ 2 ' ; l B z <l'.'. .J 11. ! ' , §~ ~; ,, ~ ' <l'.'. .J ! ~ ~ ~ • • " /;; J: «![~~ OciO~..., ' ' :s ~ 6 0 ro -,. < 0 ) ) City of Renton TREE RETENTION WORKSHEET 1. Total number of trees over 6" in diameter1 on project site: 1. ____ ? __ trees 2. Deductions: Certain trees are excluded from the retention calculation: . .Trees that are dead, diseased or dangerous2 _...,o'---trees Trees in proposed public streets o trees Trees in proposed private access easements/tracts o trees Trees in critical areas 3 and buffers O trees Total number of excluded trees: 3. Subtract line 2 from line 1: 2. ---'-o-----'---trees 3. __ ...:?c___ trees 4. Next, to determine the number of trees that must be retained4, multiply line 3 by: 0.3 in zones RC, R-1, R-4, or R·B 0.1 in all other residential zones 0.05 in all commercial and industrial zones 4. __ 2.1 trees 5. List the number of 6" or larger trees that you are proposing 5 to retain 4 : 5. 2:.--'(.___ trees 6. Subtract line 5 from line 4 for trees to be replaced: 6. __ ,0 l trees (If line 6 is less !liar, zero. slap here. No replacement trees are required)- 7. Multiply line 6 by 12" far number of required replacement inches: 7. --1~'~-inches 8. Proposed size of trees to meet additional planting requirement: 11 (Minimum 2" caliper trees required) 8. _ __:'!;:::._ ____ inches per tree 9. Divide line 7 by line 8 tar number of replacement trees 6: (if remainder is .5 or greater, rolind up !o the next whole number) 1 Measured al chesl height. 9. __ b ___ trees ;; Dead, diseased or dangerous 1rees rnust be certified as such by a forester, registered far,dscape architect, or certified arborist. and ;:;pproved by the City. 3 Critical Ar~as, stich :::is wetlands, streams, iloodr::lalns and protected slopes, are defined tn Section 4-3·050 of 1he Ren!on Munldpal Code (RMC) 1 Count anfy those trees to be retained outsJde of crWcal areas and buffers. 5 · ihe City may require modification of 1he tree retention plan !o ensure retention of the maximum number at !mes per AMC 4-4-l30H7a E. Inches of street trees. inches of trees added to critical areas/buffers, and inches of trees retainaa on site th.at are less than 6" but are greater than 2" can be used to r.eet the tree replacement requirement. , H: \CE D\Dm a \Forms Temp ]ates \Se! f-Help Hand outs \P 1 an n in g\ Tree Reten; ion \liorks!v..:ec doc 12108 Exhibit A.7 Ph 253-896-HlH .Fx 253-896-2633 WH Hughes Company, Inc. 14404 Issaquah-Hobart Road, Suite 104 Issaquah, Washington 98027 ( 425) 444-3367 Mr. Bi/I Hughes GeoResources, LLC 5007 Pacific Hwy E., Ste. 16 Fife, Washington 98424 December 22, 2014 Geotechnical Engineering Report Proposed Short Plat NE 241" Street Renton, Washington PN: 813210-0120 &-0130 Job No. WHHughes.NE24thSt.RG INTRODUCTION & SCOPE This report presents the results of our subsurface explorations, literature review, and engineering analysis and provides geotechnical design recommendations for the proposed short plat to be constructed on NE 24'" Street in Renton, Washington, as shown on Figure 1. The site is currently undeveloped. The short plat will consist of three residences, two that occupy the bottom two thirds of each parcel, and the third occupies the top one third of each parcel. The short plat will be accessed via three new driveways, two of the proposed driveways will extend north from NE 241 " Street to the residences on the southern parcels, while the third driveway will extend between the two southern parcels back to the north lot. We anticipate that the residences will be 2-story, wood-framed structures supported on conventional spread and continuous concrete foundations. The remainder of the site will be covered with grass lawn and landscaping. Current site conditions and topography is included as Figure 2. The purpose of our services was to evaluate the surface and subsurface conditions at the site as a basis for developing and providing geotechnical engineering and stormwater management recommendations for the proposed development. Specifically, our scope of services for the project included t11e following: 1. Visiting the site and conducting a geologic reconnaissance to assess the site's soil, groundwater and slope conditions; 2. Exploring the subsurface conditions by excavaiing four test pits across the site; .3. .A.ddressing the City of Renton Critical Areas Ordinance for potential geological hazards; '1., Providing geotechnica! design recommendations for foundation, floor slab, and pavement; and 5. Providing infiltration rates for the stormwater facility, as appropriate:- Entire Document Available Exhibit A.8 1 • ' Ex1.~g.m,~.~.~s V PRELIMINARY TECFINICAL INF0Rlv1ATI0N REPORT for NE 24'h 3-Lot Short Plat 24XX NE 24'h St. Renton, WA 98059 December 29, 2014 Encompass Engineering .Job No. 14690 Prepared For Bill Hughes 14401 Issaquah-Hobart RD Issaquah, WA 98027 Exhibit A.9 Entire Document Available Uoon Request YVestern '\'Vashfngton Division Eastern Wa.,hingtnn Di1·ision l 65 NE Juniper St., Ste 20 I, Issaquah, WA 98027 Phone: Cl2.5) J'l:C-0250 F:ix: 1·+25) ·.i91-J055 I 08 East 2"' Street, Cle Elum, \VA 98922 Pfi"ne: (509167.j-7"33 Fax: !509) 674-7419 \N 1.vw. Encompa~sE.S. net "°', ~ 0 En~,QHJJ2,?,?s V December 24, 20 l 4 Steve Lee, Development Engineering l\,fanager City of Renton 1055 S Grady Way, 6th Floor Renton, WA 98057 RE: NE 24th Street 3-Lot Short Plat Street i\,fodification Request Dear Steve; We are working on a preliminary short plat dividing 2 existing residential lots into three Jot. We have been asked to provide, per code, a minimum RJW width of 53', a 26' wide paved road with 0.5' vertical curbs, 8' wide landscape strip, a 5' Vvide sidewalk, and street lights. Existing RJW width of60'. On the 30' subject side (north side) of the R/W, there is existing 18' of asphalt paving, a vertical curb, a 6.5' planter strip, a 5' sidewalk and four street trees and two spaced street lights in the planter strip-the sidewalk is butted up against the R/W. On the opposite side there is existing 16' of asphalt paving (total 34'), a vertical curb, and a 5' sidewalk (most of the way). The existing roadway is nice and provides the required more roadway than is currently required and also provides the required pedestrian improvements. The 6.5' planter strip is functioning as well. The existing street meets the required standards except that the planter strip is 6.5' rather that the code- specified 8'. Because the paving width is 2' wider on the subject side of the R/W, there is no room in the RJW for an additional 1.5' of planter strip without removing the curb and reconstructing it 1.5' into the existing roadway. We request that the frontage be allowed to remain as is without providing the additional 1.5' of planter strip. If you have questions or need additional information, please call me at 425-392-0250 or email me at trcdding@encompasses.net Sincerely, Encompass Engineering ~(~DDr,vc, Tom Redding Western Washington Division 165 NE Juniper St., Ste 20 I, Issaquah, WA 98027 Phone: (425) ]92-0250 Fax: (425) 391-3055 Exhibit A.10 Entire Document Available Uoon Request Eastern Washington Division 108 East 2"' Street, Cle Elum, WA 98922 Phone: (509) 674-7433 Fax: (509) 674-7419 SECTION 3 OFF-SITE ANALYSIS Site Address: King County Tax Parcels: Project Overview 24XX NE 24th St., Renton, WA 98059 813210-0120 and 813210-0130 This project involves the development of two vacant parcels totaling 0.58 acres into three single- family lots in the Kennydale area. These parcels are located within Northeast Section 05, Township 23 North, Range 5 East, W.M. The existing topography of these parcels generally slopes down to northwest at approximately 10% to 25%. The existing parcels are vacant and is covered with lawn and several mature trees. Per the USDA Web Soil Survey, the site is underlain with Indianola fine to medium sand. -Refer to Sec. 6 of this TIR for geotech report and infiltration test results prepared by Geo Resources. Downstream Drainage Level I downstream analysis for this project was conducted on Dec 18, 2014. The weather on the day of the site visit was cloudy and rainy with the temperature of approximately 50oF. Runoff from the existing project site apparently infiltrates into the underlying sandy soil. That that will not infiltrate would sheet flow to northwest and drains through adjacent property on the northwest and then enters into a biofiltration swale located at point A, about 70-feet downstream from the project site. From there, flow drains through the swale and at the end of the swale enters into a 15-inch pipe. Then, flow continues west through the pipe and enters into a storm drainage manhole located at point B for a total of approximately 160-feet downstream from the project site. From there, flow continues west through a 15-inch pipe and enters into a storm drainage manhole along the west side of Kennewick Ave NE located at point C for a total of approximately 200-feet downstream from the project site. From there, flow continues south through a 15-inch pipe and enters into another storm drainage manhole located the intersection of Kennewick Ave NE and NE 24th St at point D for a total of approximately 430-feet downstream from the project site. From there, flow continues west through an 18-inch pipe and enters into another storm drainage manhole located at point E for a total of approximately 650-feet downstream from the project site. From there, flow continues west through an 18-inch pipe and enters into another storm drainage manhole located at point F for a total of approximately 780- feet downstream from the project site. From there, flow continues west through a pipe and crosses the Jones Ave NE and enters into another storm drainage manhole located at point G for a total of approximately 900-feet downstream from the project site. From there, flow continues west through a pipe and apparently enters into another storm drainage manhole at point H for a total of approximately 1, 130-feet do\l\instream from the project site. From there, flow discharges to the north side of the street through an 18-inch culvert pipe at point H into a heavily wooded but rocked channel of Kennydale Creek, about 3 ' wide, 6' deep flowing northwest at point J. About 15 0 -feet beyond the NE 24th Street R/W the flows pass through a tall fence. Because of tall fences and locked gates, the stream could not b e followed any further. Apparently the stream ente rs a storm conveyance system at the I-405 sound wall another 150-feet further, about 1,430- feet downstream from the project si te. There were no apparent drainage problems along the downstream drainageway. See Oo\\.'Tl.Stream Map and Photo 's I through 5 below. ...i..;:::; Photo 1 : View of the subject properties-Sheet flow northwest Photo 2: Infiltration swale at point A Photo 3: SOMH at point B Photo 4 : 18-inch culvert pipe at point I Photo 5: Stream channel at point J r . ! I : !, j! ··, -,,1 I '; 1 'DI!, \ \ \ i_ :I I, ~ i ; I , ' I J I I I l ' ' l ' ' ' I ... ~ t ' I . ! l t \ ' \ \ '"'"~-) ) ' '1 \ I i _( ) / / DOWNSTREAM DRAINAGE MAP .. "'--... ' !\ I lt ( _,,/ /' ----. \ \,_ i' \..., •· ... \ \ \\ \ \ i . \ '· \ ------.. -............. ·--~~.\,. '"•. ~----\ ·---. \ '·-. _______ . / .. · 1 \\ ' \ i '. ·--. "'· c I I ! ~ ... ·· .. , ,._, -~ i \ ·-.. , \ Ji \ ! ·,_ l I ! I ' f /,,/ ', \ \/ \,',,,,, \ I ! ! I .. ,, l ' -,--I '· .. \. __ ~-\____ \ ",,.~-----.. __ _.... ,_ .. :·-~---~--.··,. .. tl \ ---.. -~ -----------. . ·---1 \ I ~'; .... _ ---·, ~ ·,J (-·. --._ ··-.. ·,. 1\ i 1 '·) \.,, '1 ·, ' ' ! ! I"' . ~ ( ..., i ' ,, I \ • \ ,, ' / ..i(; ' .J •' -.. :. \ '·----. ' ) 1, ~--~ ,' \. -.,_ ! --· • . I , ·, ·, ' .\ f i 1 \ ..--.,/ 11 \ I / I ;a~ ''\'' -. t I lj 1....._-....,..--... f ~ i1 ! J ; '1 J 1 .. \ I J J \ ...-r\ .' / -.. I ,' ! '1 ~-. / \ '· \ .... \ ' ' ·, ,-J 1 1 i' ·-. ., ~ ' ' f \ /. '[ '· i r~ 1 ,. I ,' ·-. J. , ____ ,. .;} i,.. ... ~ _.,..-' _... ----,. Vt / ___ ,.,-" • l t--J ! \ ~ -~ ,.a ,,-i: ~' \\\ ~-·/' -\ Jf /" "'-.i. ~ j s I-."~ •, ,, l • I ,, ', ' ' ', . ' ~-' ' \ \ ' • ,.-'1 ) ,.--' I ~ J .i\ . \"' ' l ' ' ' f ;' ! ~ i • ,1 .N ·1 \ I r , ;:, l ~ 1 1 '".._...,..1~,, / '"-._.-· \ 1 -.Renton i ~ ,I / / ,, ' • I ', ', ' ' I . E:/ ) 1, --~. ' J / / I ' I \ '·. \ \, \,_.,,., i / . i ( ' . . . ·, I --' i , •. ,' 't '; ',I L/ \ __ '. \ _ .-I r / ,i: ® .. .,..,(F) ·,, . ' ,, , I ~ 1 ~ \_ 1 0. \ l •, I i' I \ ! I I . . -' ... .-• ..... J ! " • \ ' 19\ ~ --·-----·--,_ 1' -.-· _I .·' ,111 ·, I ·, !_ \ell ,,,...--I' .. 1 f ' I I ' J ! I i . ·~-. c-acp,sr l...11 ·i i. \ \, \. l ' -. -• ' ' . ' •, . l I ---~ -.• ,_ ·,,_ ··, ,, ··, 1· ··~--. , '·. II I ---'\ -\ -\, / . \.-. ( ./' ·' "----. ·\, \\ Ii • ....,__' /! \ \ / 1 :' ./ ,.... ·..... \ \,, \ , • \ '-I ., -' i" .. ~ l I I I f l 1 \ -,.. j -· . .... f / . ~ .• j ii I 1· ,, I '-_j 1· ~ I ., ,.. I '· I I I 1 ; 0 / "' -f I 1 ( j ! '1 • ··-~ ...., '· [ I i ) /' I 'j I I I -. . . I ' • ,· ·, . i -'_··_ ! 1 / ·1 '1f1 ; ., ". j I l ,, ' I ' \, ' ' I I I I ! I / 1··-----· .. __ ·, ·~ . ' r r' i I ' . ft ·-.. --.. , ,, --·-. . . 1 :1 -----~, 1._ f. \ ./ I. -___ .. '1/ I I • -.. •• ,.. 1~L. . r ·· ----,.. ... ii J --~ ·-· ... ,., ,, · .. ,_ .. -. #$ \ ' i •' ... , :1 ___ 1' / , , ,,, \ ) z~ .. £:b..orr1 i ,, 1: ~ I ! ! l ' '! j ;I -:.. 1-1; \ I. ! /, '--~\ i' J ! 1' 1 1 1 i -;: '\ 1 ... ,1 : '1 ,i ) !:i!_. 1: \ \ '.fl \1 ,, ... 1' lj '1/_~/' I 'I l ! i,_ '·· ,A.I -I "" ' I .• +·Ii i ( I 1 1 1' l , W"I 11. -. , -i t I '1 ol i I / , ! .. , ----~ .!I -.__ ·, .. , ,, .. , 1· .I r ·1 I[" ~o , .. _ ·-... . __ .. -· ·y, ,, , ,_ ,. .. I . I L. ---· ... _ . ·-. I ·1 ', ', . i 1' I . --,. t, l j i l i i -.. \ i ' \ ··----/f ,I J I iCJ2008Km,g'~~-;at·11 \ \ II ,/ ', (3 ,... l20,l!ft --~- .• ( '11 I ' N \ 1" = 100' \ \ .. _ The information included on this ma~ has been cc:irripiied b~King County staff fr6m a varlefy of sources ani:fTssubject to change without notice i(ing County makes .~o represenlat1ons or warranties. express or implied. as to accuracy, completeness. timeliness or nghts to the use of suer. ,ntormallon This document is not intended tor use ..,. a swvey oroduet King Coufll)I J ti shall not be liable for any genera1. special indirect, ,n_cidental or consequel'lt1a, damages including, but ,,ot limited to. 1ost cevenues or 10_ st profits resulting trorn the usa or misuse of the ~ Kinn Count 111tormaVon contained on this map Any sale of this map or ,ntorrnanon on this map 1s prohibited except by wntten perm1as1on of King Coul1fy I · •• •• y Date: 12/1712014 Source King County IMAP Property information (http://www.metrokc.gov/GISliMAP1 i I I SECTION 4 FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN I I Proposed Drainage Controls Infiltration trenches will be used on the lots to provide full infiltration. Per the geotech report, the site is underlain with fine to medium sand. Full infiltration trenches were sized to provide I 00-yr infiltration. Per the attached KCRTS analysis, 24.1 LF of trench per I 000 sq-ft of impervious surface will provide I 00-year flow control. I I Encompass Engineering & Surveying Eastern Washington Division 407 Swiftwater Blvd .• Cle Elum. WA 98922 Phone (509) 674-7433 Fax (509) 674-7419 Western Washington Division 165 NE Juniper St., Suite 201, Issaquah, WA 98027 Phone (425) 382-0250 Fax (425) 391-3055 SHEET NO.--------OF_~---- CALCULATEDBY_~f~/~2-, ____ DATE 1/t,/J~ CHECKEDBY ________ DATE _____ _ SCALE---------------- t /\J FcP Trlt+ n G'fJ Wt'f't:.:tf,; s .. lJ._/ / l. '-. Rf US fz P . __ ()_ f>J NEw t "-ft n-l(top ~~ ... . ... . .... ··········I ... -P!ft., Ct€-ctfiM-/-f7 1 A/Ft L TY?J"'?,17 t)/1..\ ~~I~ 1 l?fisu LT$ -~ . .. . . . Noa."" r CPE. z '"-' El L Mr? i2 () N TJJ<; T"<:;:, . ~ . /,, 7= , NctlFJ 5/!.,JL)£.J/Z_::::-I ..... ,..eA'D 1re-::,r1Nt;_ ;: &_,..7,0 Ppw,.c.1 .,.._ :::. -iP~80 1 , oaf I w T ...,,5'(~- Fi.: G°O"'"(. Ii' h'--:f . :::. 4 T> /i.J t-c:i,&§ ::: 4~ ~+-o.•a s . =c .. ts, .o -£ 9 l~ e; .. (fat;'!) Encompass Engineering & Surveying Eastern Washington Division 407 Swiftwater Blvd., Cle Elum, WA 98922 Phone (509) 674-7433 Fax (509) 674-7419 Western Washington Division 165 NE Juniper St., Suite 201, Issaquah, WA 98027 Phone (425) 382-0250 Fax (425) 391-3055 SHEETNO -------OF_~---- CALCULATED SY __ --LJ L-J2..... ____ DATE 1/1¢.5 CHECKED BY _______ DATE----- SCALE -9 I t,~4 ,_, = l-1>1:s, "".,,.,*' 1-1-(F:---_ l 5,._., , o/1 Nc,lf ---6() 1'<,1{\i " --- TJ :PS J "fc fl-./ Y(Yt1-StJt20 ~p,Fr &7E !Mfff{L//tf,)(,/5_ ~v,.i Fif-i~ ()'St~ 4 fZl.12-rs {,tiffs HR1ii -- ' . -7. { _s_·_ -__ -__ --_-_!--:· .. _-:::::::::-. ~=i===_ ~===--::::::::::.._ ~-= c -;: Encompass Engineering & Surveying Eastern Washington Division 407 Swiftwater Blvd., Cle Elum, WA 98922 Phone (509) 674-7433 Fax (509) 674-7419 Western \Vashington Division 165 NE Juniper St., Suite 201, Lssaquah, WA 98027 Phone (425) 382-0250 Fax (425) 391-3055 JOB---------------------- SHEET NO -----------OF ________ _ CALCULATED BY---------DATE -------- CHECKED BY __________ DATE-------- SCALE ---------------------- ~11vt .. ~tV0Vfrt ...... })"ei;;! ,t /....;. , 1v F, L 'JYZt<J.. n (.j ,._ -· ---. ·--------. --" " -. "~--- \ - \ ~'--, '· ""'<----~-"--------~----~ ........... _ ·r@s·· ...... ....... v-=. ."?-3t.P 11v;:,'-lnl! i2s&. ..... 1tZEAcil y -~·· KCRTS Peaks for 5,000 sq-ft Impervious Surface Flow Frequency Analysis Time Series File:14690d.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.028 7 2/09/01 2:00 0.024 8 1/05/02 16:00 0.034 3 12/08/02 18:00 0.028 6 8/26/04 2:00 0.034 4 10/28/04 16:00 0.030 5 1/18/06 16:00 0.042 2 10/26/06 0:00 0.054 1 1/09/08 6:00 Computed Peaks -----Flow Frequency Analysis------- --Peaks Rank Return Prob (CFS) Period 0.054 1 100.00 0.990 0.042 2 25.00 0. 960 0.034 3 10.00 0.900 0.034 4 5.00 0.800 0.030 5 3.00 0.667 0.028 6 2.00 0.500 0.028 7 1. 30 0.231 0.024 8 1.10 0.091 0.050 50.00 0.980 100-yr 100-year Infiltration Trench Design of 5,000 sq-ft Impervious Surface Retention/Detention Facility Type of Facility: Gravel Infiltration Trench Facility Length: Facil.i ty Width: 72.00 5.00 360. 2.00 0.00 216. 14.90 ft--* 14.4LF/1000 sq-ft impervious ftV Facility Area: Effective Storage Depth: Stage O Elevation: Storage Volume: Vertical Permeabil.ity: Permeable Surfaces: Riser Head: Riser Diameter: Bottom sq. ft V ft v' ft cu. ft v min/in V 2.00 ft V 4. 00 inches v' Top Notch Weir: None Outflow Rating Curve: None Stage (ft) 0.00 0.02 0.12 0.22 0.32 0.42 0.52 o. 62 0.72 0.82 o. 92 1. 02 1.12 1. ?7 1. 32 1. 42 1. 52 1. 62 1. 72 1. 82 1. 92 2.00 2.10 2.20 2.30 2.40 2.50 2.60 2.70 2.80 2.90 Elevation (ft) 0.00 0.02 0.12 0.22 0.32 0.42 0.52 0.62 0.72 0.82 0.92 1. 02 1.12 1. 22 1. 32 1. 42 1. 52 1. 62 1. 72 1. 82 1. 92 2.00 2.10 2.20 2.30 2.40 2.50 2.60 2.70 2.80 2.90 (cu. Storage ft) (ac-ft) 0. 0.000 2. 0. 000 13. 24. 35. 45. 56. 67. 78. 89. 99. llO. 121. 132. 143. 153. 164. 175. 186. 197. 207. 216. 216. 216. 216. 216. 216. 216. 216. 216. 216. 0.000 0.001 0.001 0.001 0.001 0.002 0.002 0.002 0.002 0.003 0.003 0.003 0.003 0.004 0.004 0.004 0.004 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 Discharge (cfs) 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.103 0 .188 0.230 0.266 0.297 0.326 0.352 0.376 0.399 Percolation (cfs) 0.00 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 3.00 3.00 216. 3.10 3.10 216. 3.20 3.20 216. 3.30 3.30 216. 3.40 3.40 216. 3.50 3.50 216. 3.60 3.60 216. 3.70 3.70 216. 3.80 3.80 216. 3.90 3.90 216. 4.00 4.00 216. Hyd Inflow Outflow Peak Target Cale Stage 1 0.05 0.00 0.00 2.00 2 0.04 ******* 0.00 0.23 3 0.03 ******* 0.00 0.03 4 0.03 ******* 0.00 0.02 5 0.03 ******* 0.00 0.02 6 0.03 ******* 0.00 0.02 7 0.03 ******* 0.00 0.02 8 0.02 ******* 0.00 0.01 Route Time Series through Facility Inflow Time Series File:14690d.tsf Outflow Time Series File:rdout Inflow/Outflow Analysis Peak Inflow Discharge: Peak Outflow Discharge: Peak Reservoir Stage: 0.054 0.000 .2 00 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 Elev 2.00 0.23 0.03 0.02 0.02 0.02 0.02 0.01 CFS at CFS at Ft Peak Reservoir Elev: 2 DO-Ft Peak Reservoir Storage: 216. 0.005 Flow Frequency Analysis Time Series File:rdout.tsf Project Location:Sea-Tac Cu-Ft Ac-Ft 0.420 0.03 0.441 0.03 0.460 0.03 0.479 0.03 0. 497 0.03 0.515 0.03 0.532 0.03 0.548 0.03 0.564 0.03 0.579 0.03 0.594 0.03 Storage (Cu-Ft) (Ac-Ft) 216. 0.005 100-l'.r 24. 0.001 Desi!!!!; 3. 0.000 2. 0.000 2. 0.000 2. 0.000 2. 0.000 2. 0.000 6:00 on Jan 9 in Year 8 9:00 on Jan 9 in Year 8 ---Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks --Rank Return Prob (CFS) (CFS) (ft) Period 0.000 6 2/09/01 2:00 0.000 2.00 1 100.00 0.990 0.000 8 1/05/02 16: 00 0.000 0.23 2 25.00 0. 960 0.000 4 12/08/02 18:00 0.000 0.03 3 10.00 0.900 0.000 7 8/26/04 2:00 0.000 0.02 4 5.00 0.800 0.000 3 10/28/04 17:00 0.000 0.02 5 3.00 0.667 0.000 5 1/18/06 16:00 0.000 0.02 6 2.00 0.500 0.000 2 10/26/06 1:00 0.000 0.02 7 1. 30 0.231 0.000 1 1/09/08 9:00 0.000 0.01 8 1.10 0. 091 Computed Peaks 0.000 1. 41 50.00 0.980 PLAN VIEW NTS 4" PVC PERFORATED PIPE ROOF DRAIN YARD DRAIN OR CB SUMP WITH SOLID LID INFILTRATION TRENCH PLAN VIEW NTS 4-" PVC PERFORATED PIPE -LEVEL- WASHED ROCK 1 r-r l~LF PER 1,000 SQ. FT. 1--~ IMPERVIOUS SURFACE ---1 l____ A ROOF DRAIN OVERFLOW SPLASH BLOCK ~~t-5.0' MIN YARD DRAIN OR CB SUMP W/SOLID LID COMPACTED BACKFILL ~-4" PERF PIPE 1 f -f WASHED ROCK INFILTRATION TRENCH DETAIL SECTION 5 CONVEYANCE SYSTEM ANALYSIS AND DESIGN NIA-No conveyance SECTION6 SPECIAL REPORTS AND STUDIES Ph. 253-896-1011 Fx. 253-896-2633 WH Hughes Company, Inc. 14404 Issaquah-Hobart Road, Suite 104 Issaquah, Washington 98027 ( 425) 444-3367 Attn: Mr. Bill Hughes GeoResources, LLC 5007 Pacific Hwy. E, Suite 16 Fife, Washington 98424 April 23, 2015 Supplemental Letter -Infiltration Testing Proposed Short Plat NE 241" Street Renton, Washington PN: 813210-0120 & -0130 Job No. WHHughes.NE24thSt.L We previously prepared a Geotechnical Engineering Report for the site dated December 11, 2014. On March 27, 2015 we returned to the site, monitored the excavation of two test pits and performed in-situ infiltration tests in general accordance with the EPA Falling Head Percolation Test Method (KCSWDM Section 5.4.1 ). Our supplemental test pits and infiltration testing were summarized in our March 31, 2015 Addendum Report. According to the KCSWDM Section C.2.2.2, infiltration devices are not allowed in critical areas buffers or on slopes steeper than 25 percent. The manual requires that for infiltration devices on slopes steeper than 15 percent or within 50 feet of a landslide hazard area or a steep slope hazard area, must be approved by a geotechnical engineer or engineering geologist. Based on an excerpt of the proposed site plan provided by Tom Redding, Encompass Engineering and Surveying, the proposed galleries for Lot 3 will be situated in areas of slopes as steep as 22 to 25 percent, with slopes of 25 to 28 percent located above the proposed gallery. Based on topographic information reviewed on the King Count iMap website and client provided site plans, the site slopes flatten offsite to the northwest. As currently proposed, the top of the gallery was to be about 6 inches below grade. Based on the site topography, we recommend that that the gallery be deepened so that the top of the gallery is 2 feet below grade. This will lower the bottom of the infiltration gallery to about elevation 268, or about the same elevation as the flatter, northwest corner of the parcel. • Given that the soils explored in our test pits consisted of a uniform sand and that the slopes flatten downslope of the galleries, it is our opinion that the proposed infiltrations on Lot 3 and Lot 2 can be constructed in the locations proposed with minimal impacts to the existing site slopes. • •• WHHughes.NE24thSt.L(2).doc April 23, 2015 Page2 We have appreciated working for you on this project Please do not hesitate to call at your earliest convenience if you have any questions or comments. Respectfully submitted, GeoResources, LLC • KSS:DCB:kss Keith S. Schembs, LEG Principal Doc ID: WHHughes.NE24thSt.L(2).doc Attachments: Site Plan Excerpt CC: Encompass Engineering and Surveying "165 NE Juniper Street, Suite 201 Issaquah, WA 98027 Attn: Mr. Tom Redding (425) 392-0250 Dana C. Biggerstaff, PE Principal / ET HILLS G. 52 1'\'11('.) C, l{. \ f'/ { \ V ' --------,E FENCE 0 5 10 20 1,.,. • ! I SCALE 1" = 20' LOT 10 1 s· 1 EX. 6' WOOD FENCE LOT 14 1 o· 0.8' 1 162.62' ----=;=-ur,~~~,""'~[J=I--J . ---T -, -~ -. --+ I / & ·=rr _ _ S89'07']_0"W __ r v ~ -____LT_ :::;:,'-:0./_ -- . 5:?,..:·. "2 ·' ~" / // /,.,/· ,,/ k,A s / / / ,/ C..l.,:,( 2. ,1)·" / ·-J/ // ·7 r..: 7 --------// W" / ,/' -~-- / / ,/ 22&// . /~/ / .--i I ., / ____ / I -~ '":1+~-:7-<:______ _i }/ y -t .. \/1 / /----7' ~ / " ~ / I /, T ?Z ------( , c:i <ol . 'V ii FEI le:,/ / 2. ' / / .~o' / / I JC // // ( / fa9"0:?,'20"W //I./ LO /~--..., ,// I /~ ~- / J /j gtWs:i.1 _, / ;/!. I ·1 /, V , , . / ; / j / . ' / I I _/ . ' ' ' / I / , / / /~• i. 1 · ' /t/. I/ I ~LO T LINE/ L~T 13 / // . // ')Cl I -__ , 7 I / / / . ::.J / . // / , '2 'J'B WI i ± ,1 / / ·T / -Of/'./l I r4'8-U +~----j / / ~ -o· $00 , ~-IE; .0 _,/ , / // · 3.oo/ ......---T/ I --11:5.6 / / / 91.12 / / . / I I // / ( EXIS "-'I GA" I I;,_, . TRI .. ~ .. -~ Ph. 253-896-1011 Fx. 253-896-2633 WH Hughes Company, Inc. 14404 Issaquah-Hobart Road, Suite 104 Issaquah, Washington 98027 ( 425) 444-3367 Mr. Bill Hughes GeoResources, LLC 5007 Pacific Hwy. E, Suite 16 Fifo, Washington 98424 March 31, 2015 Addendum Letter -Infiltration Testing Proposed Short Plat NE 24 1h Street Renton, Washington PN: 813210 -0120 & -0130 Job No. WHHughes.NE24thSt.L This letter summarizes the result of our recent infiltration testing for the proposed short plat site located on the above referenced parcels on NE 24th Street in Renton, Washington. We previously prepared a Geotechnical Engineering Report for the site dated December 11, 2014. On March 27, 2015 the owner excavated two additional test pits in the locations of the proposed infiltration galleries. The two supplemental explorations were excavated in the northwest corner (IT1) and near the center {IT2) of the project site, as shown on the attached Site Plan, Figure 1. We performed in-situ infiltration tests, as required by the City of Renton, in general accordance with the EPA Falling Head Percolation Test Method (KCSWDM Section 5.4.1). Our tests were performed at depths of approximately 6 to 12 inches at the bottom of the two test pits. The test pits were excavated to depths of 90 and 88 inches respectively. Based on our site observations and visual classifications in accordance with the USCS, it is our opinion the sandy soils observed in the November 24, 2014 test pits are representative of soils observed, classified in our previous test pits, summarized in our December 2014 report. However, during our recent site visit, we observed the surficral soils at IT2 appeared to have been reworked and contained fill, debris, and organics. Test pit logs of the two supplemental explorations are attached as Figure 2. During the presoak time, we noted that 12 inches of water completely drained within 10 minutes, therefore the prescribed 4-hour presoak was not required. During testing, water levels were filled to 6 inches above the bottom of the hole. IT1 has a measured infiltration rates of 17.6 inches per hour while IT2 had a measured rate of 16.7 per hour. Using the simplified method outlined in Section 5.4.1 of the KCSWDM Section 5.4.1, the design engineer should apply the following corrections factors: • F1esling = 0.30 for EPA Method • Fgeometry = determined by Civil Engineer • F ,,uggmg = 0.80 for fine sands and loamy sands We have prepared this report for WH Hughes Company, Inc. and other members of the design team for use in evaluating a portion of this project. Our report, conclusions and WHHughes.NE24tf1St.lLa.doc March 31. 2015 Page 2 interpretations are based on data from our limited subsurface explorations and reconnaissance, and should not be construed as a warranty of the subsurface conditions. Variations in subsurface conditions are possible between the explorations and may also occur with time. A contingency for unanticipated conditions should be included in the budget and schedule. Sufficient monitoring, testing and consultation should be provided by our firm during construction to confirm that the conditions encountered are consistent with those indicated by the explorations, to provide recommendations for design changes should the conditions revealed during the work differ from those anticipated, and to evaluate whether installation activities comply with contract plans and specifications. Our recommendations are not intended to direct the contractor's methods, techniques, sequences or procedures, except as specifically described in our report for consideration in design. If there are any changes in the configurations or type of facilities to be constructed, the conclusions and recommendations presented in this report may not be fully applicable. If such changes are made, we should be given the opportunity to review our recommendations and provide written modifications or verifications, as appropriate . • • • We have appreciated working for you on this project. Please do not hesitate to call at your earliest convenience if you have any questions or comments. Respectfully submitted, GeoResources, LLC • KSS:BPB:kss J/ J --/j '1-{J{;~ (?W/1/t'-' Dustin Taylor, EIT j Staff Engineer in Training Keith S. Schembs, LEG Principal Doc !D: WHHughes.NE24thSt.!La.doc Attachments: Figure i ~ Site Plan Figure 2 -Test Pit Logs BRADLEY P BIGGERSTAFF Brad P. Biggerstaff, LHG Principal Approximate Site Location (rnap created Imm the King County iMap http://www5.k1ngcounty.gov/ilvlAP/i I 'I\ , ~-~ -w-~(E s GeoAesources, LLC 5007 Pacific Highway East. Suite 16 Fife, Washington 98424 Phone: 253-896· i 011 Fax: 253-896-2633 Site & Exploration Plan Proposed Short Plat NE 24'h Street Not to Scale_ . I·-. ________ R_e_n_.t_o_n~. _w_A----~--. ~ i Job: WHHughes.NE24thSt.F Nov 2014 Figure 1 ! '----------s---·-----------~--~--L.-., ~--" -----------------------------------·----- Test Pit Log IT-1 Location: NW corner of back third lot __ Depth (feet) Soil Type 0 114 Soil Description --"~~=--=~--=~------------·---------Sod over Topsoil y. 11/2 SP Orange brown fine to medium SAND with some silt to silty, trace roots (med dense, moist) 1 Vz 6V2 SW Light brown coarse SAND (loose to med dense, moist) 6112 71/2 SP Light brown medium SAND with some gravel and trace silt (med dense, moist) Test pit terminated at about 7.5 foot below existing grade. No caving observed, No groundwater seepage observed. Test Pit Log IT-2 Location: NW corner of eastern front lot Depth (feet) Soil Type Soil Description 0 1h Sod over Topsoil V2 2 SP Orange brown fine to medium SAND with some silt, trace roots (med dense, moist, reworked with some fill) 2 TV2 SP Light brown medium SAND with trace silt and roots (med dense, moist) Test pit terminated at about 7.5 feet below existing grade. No caving observed, No groundwater seepage observed. Excavated on: March 27, 201_5 __________ ~--------------------"Lo"',a=a'e=-d=-bvzc::-=D"-R'-'T--I GeoResources, LLC 5007 Pacific Highway East, Suite 16 Fife, Washington 98424 Phone: 253-896-1011 Fax: 253-896-2633 Test Pit Logs Proposed Short Plat NE 241h Street Renton, WA ~-------------~-----~------< [ March 2015 ( Job: WHHughes.NE24thSt.F Figure 2 Ph 253-896-1011 Fx 253-896-2633 WH Hughes Company, Inc. 14404 Issaquah-Hobart Road, Suite 104 Issaquah, Washington 98027 (425) 444-3367 Mr. Bill Hughes GeoResources, LLC 5007 Pacific Hwy E., Ste. 16 Fife, Washington 98424 December 22, 2014 Geotechnical Engineering Report Proposed Short Plat NE 24'" Street Renton, Washington PN: 813210 -0120 & -0130 Job No. WHHughes.NE24thSt.RG INTRODUCTION & SCOPE This report presents the results of our subsurface explorations, literature review, and engineering analysis and provides geotechnical design recommendations for the proposed short plat to be constructed on NE 24th Street in Renton, Washington, as shown on Figure 1. The site is currently undeveloped. The short plat will consist of three residences, two that occupy the bottom two thirds of each parcel, and the third occupies the top one third of each parcel. The short plat will be accessed via three new driveways, two of the proposed driveways will extend north from NE 241" Street to the residences on the southern parcels, while the third driveway will extend between the two southern parcels back to the north lot. We anticipate that the residences will be 2-story, wood-framed structures supported on conventional spread and continuous concrete foundations. The remainder of the site will be covered with grass lawn and landscaping. Current site conditions and topography is included as Figure 2. The purpose of our services was to evaluate the surface and subsurface conditions at the site as a basis for developing and providing geotechnical engineering and stormwater management recommendations for the proposed development. Specifically, our scope of services for the project included the following: 1. Visiting the site and conducting a geologic reconnaissance to assess the site's soil, groundwater and slope conditions; 2. Exploring the subsurface conditions by excavating four test pits across the site; 3. Addressing the City of Renton Critical Areas Ordinance for potential geological hazards; 4. Providing geotechnical design recommendations for foundation, floor slab, and pavement; and 5. Providing infiltration rates for the stormwater facility, as appropriate. WHHughes.NW24thSt.RG December 22, 2014 Page2 SITE CONDITIONS Surface Conditions The undeveloped parcels are located in an area of existing residential development. Both parcels are generally rectangular in shape, measure about 81 feet wide (east to west) by 155 feet deep (north to south) and encompass about 0.58 acres total. The site is bounded by existing residences on the west, north, and east and by NE 241 h Street on the south. Site grades generally slope down from NE 241h Street to the northwest. Current grades range from about 13 to 15 percent. Total vertical relief across the site is on the order of 30 feet. The approximate site topography, and contour lines obtained from the King County iMap website is shown on the attached Site & Exploration Plan, Figure 2. The site is currently undeveloped and is mostly covered with grass lawn and a few scattered trees. A fence separates the parcel into a front and rear yard area. Site Soils The USDA Natural Resource Conservation Service (NRCS) Web Soil Survey for King County maps the soils underlying the site to be the Indianola Loamy Sand {lnC) soils. The Indianola soils are derived from sandy glacial outwash and form on slopes of 6 to 15 percent. These soils are listed as having a "moderate" erosion hazard and are listed in hydrologic soils group A. A copy of the NRCS Soil Survey for the site area is attached as Figure 3. Geologic Conditions The Washington Interactive Geologic Map, Division of Geology and Earth Resources -Washington's Geological Survey maps the site as being underlain by a sequence of recessional outwash (Qgo) that was deposited during the most recent Vashon Stade of the Fraser Glaciation, approximately 12,000 to 15,000 years ago. The Recessional outwash consists of poorly stratified sand and gravel that was deROSited ~Y meltwater streams and rivers emanating from the retreating glacial ice mass. The outwash is considered normally consolidated. An excerpt from the referenced map is included as Figure 4. Subsurface Conditions We evaluated subsurtace conditions on November 24, 2014 by excavating a series of four test pits with a small track-mounted excavator working for Geo Resources, LLC. The test pits extended to depths ranging from 7 to 7Y2 feet below the existing ground surtace. The test pits were located in the field by our representative by pacing from existing site features. The approximate test pit locations are indicated on the attached Site Plan as Figure 2 and summarized below in Table 1. TABLE 1 APPROXIMATE LOCATIONS, ELEVATIONS, AND DEPTHS OF EXPLORATIONS Test Pit Surface Termination Termination Functional Location Elevation Depth Elevation Number (feet) (feet! (feetl TP-1 SW corner of proposed east front lot -302 7¥.e 294¥.e TP-2 SW comer of proposed west front lot -292 7 285 TP-3 South of fence, between two front lots -290 7 283 TP-4 North of Qate to back lot -277 7 270 Elevation datum: King County iMap A geologist from our office continuously monitored the excavations, maintained WHHughes.NW24thSt.RG December 22, 2014 Page 3 logs of the subsurface condition_s encountered in each test pit, obtained representative soil samples, and observed pertinent site features. Representative soil samples obtained from the test pits were placed in sealed plastic bags and taken to our laboratory for further examination and testing, as deemed appropriate. Subsurface Conditions Our test pits encountered uniform subsurface conditions that generally confirmed the mapped stratigraphy. Our test pits encountered approximately 2 to 3 inches of topsoil/duff mantling a loose orange/brown fine to medium sand with some silt and roots/organics. Underlying these surficial soils, our test pits encountered a light brown medium course sand with a trace silt, the we interpret to be the mapped recessional outwash. The outwash was encountered to the full depth explored in all of our test pits. The subsurface conditions encountered in each test pit are described below in Table 2. TABLE2 APPROXIMATE THICKNESSES, DEPTHS, AND ELEVATIONS OF SOIL LAYERS ENCOUNTERED IN EXPLORATIONS Thickness of silty Depth to Elevation of Test Pit Thickness of Medium Dense Medium Dense Number Topsoil fine Sand Outwash Sand Outwash Sand (feet) (Weathered Outwash) (Outwash) (Outwash) (feet) /feet\ (feetl TP-1 Yz 4 4Y2 29711, TP-2 11, 1 1Y2 290Y, TP-3 % 114 2 288 TP-4 14 314 3Yz 27311, Elevation datum: Kina Countv iMap The soils encountered were visually classified in accordance with the Unified Soil Classification System (USCS) described on Figure 5. The test pit logs are included as Figures 6. Groundwater Conditions No groundwater seepage was encountered in our test pits at the time of digging. Based on the nature of the near surface soils, we anticipate fluctuations in the local groundwater levels will occur in response to precipitation patterns, off-site construction activities, and site utilization. CRITICAL AREA The City of Renton Critical Areas Ordinance {Ordinance 5137), Section II, Chapter B, lists the various critical areas covered by Ordinance 5137, including: 1. Lands to Which These Regulations Apply: The following critical areas, classified in subsections H.1 through M.1 of this Section, are regulated by this section: a. Aquifer Protection Areas. b. Areas of Special Flood Hazard. c. Sensitive Slopes, twenty five percent (25%) to forty percent (40%) and Protected Slopes, forty percent {40%) or greater. d. Medium, High, and Very High Landslide Hazard Areas. WHHughes.NW24thSt.RG December 22, 2014 Page4 e. High Erosion Hazards. f. High Seismic Hazards. g. Medium and High Coal Mine Hazards. h. Volcanic Hazard Areas. i. Critical Habitats. j. Streams and Lakes. The Geologic Hazards defined by Ordinance 5137 are described in Section II, Chapter J, and include: Steep Slopes a. Steep Slopes: i. Steep Slope Delineation Procedure: The boundaries of a regulated steep sensitive or protected slope are determined to be in the location identified on the City of Renton's Steep Slope Atlas. An applicant's qualified professional may substi1ute boundaries independently derived from survey data for the City's consideration in determining the boundaries of sensi1ive or protected steep slopes. All topographic maps shall utilize two (2) foot contour intervals or the standard utilized in the City of Renton Steep Slope Atlas. ii. Steep Slope Types: (a) Sensitive Slopes. (b) Protected Slopes. The site slopes typically range from 13 to 15 percent across the site. In our opinion, the slopes do not meet the definition of a steep slope area. Landslide Hazards b. Landslide Hazards: i. Low Landslide Hazard (LL): Areas with slopes less than fifteen percent (15%). ii. Medium Landslide Hazard (LM): Areas with slopes between fifteen percent (15%) and forty percent (40%) and underlain by soils that consist largely of sand, gravel or glacial till. iii. High Landslide Hazards (LH): Areas with slopes greater than forty (40%), and areas with slopes between fifteen percent (15%) and forty percent (40%) and underlain by soils consisting largely of silt and clay. iv. Very High Landslide Hazards (LV): Areas of known mappable landslide deposits. No evidence of historic or active landslide activity was observed during or site visit, nor were any areas of landslide activity or mass wasting deposits shown on or within the vicinity of the site by the Washington Interactive Geologic Map. Given the mapped and observed site slopes, we would interpret the site to be a low landslide hazard area. Erosion Hazards c. Erosion Hazards: i. Low Erosion Hazard (EL): Areas with soils characterized by the Natural Resource Conservation Service (formerly U.S. Soil Conservation Service) as having slight or moderate erosion potential, and that slope less than fifteen percent (15%). WHHughes.NW24thSt.RG Decernber22,2014 Page 5 ii. High Erosion Hazard (EH): Areas with soils characterized by the Natural Resource Conservation Service (formerly U.S. Soil Conservation Service) as having severe or very severe erosion potential, and that slope more steeply than fifteen percent {15%). The NRCS Web Soil maps the soils underlying the site to be the Indianola loamy sand (lnC) soils. The Indianola soils are listed as having a "moderate" erosion hazard. Given the site slopes and mapped/encountered soil types, it is our opinion that the site has a Low Erosion Hazard. Seismic Hazards d. Seismic Hazards: i. Low Seismic Hazard (SL): Areas underlain by dense soils or bedrock. These soils generally have site coefficients of types S1 or S2, as defined in the Uniform Building Code. ii. High Seismic Hazard (SH): Areas underlain by soft or loose, saturated soils. These soils generally have site coefficients of types S3 or S4, as defined in the Uniform Building Code. Based on our observation and the subsurface units mapped at the site, we interpret the structural site conditions to correspond to a seismic Site Class "D" in accordance with Table 1613.5.2 in the 2012 IBC (International Building Code) documents. This is based on the likely range of equivalent SPT (Standard Penetration Test) blow counts for the soil types observed in the site area. These conditions were assumed to be representative for the conditions based on our experience in the vicinity of the site. Liquefaction is a phenomenon where there is a reduction or complete loss of soil strength due to an increase in pore water pressure. The increase in pore water pressure is induced by seismic vibrations. Liquefaction mainly affects geologically recent deposits of loose, fine-grained sands that are below the groundwater table. It is our opinion that the risk for liquefaction to occur at this site during an earthquake is negligible. Coal Mine Hazards e. Coal Mine Hazards: i. Low Coal Mine Hazards (CL): Areas with no known mine workings and no predicted subsidence. While no mines are known in these areas, undocumented mining is known to have occurred. ii. Medium Coal Mine Hazards (CM): Areas where mine workings are deeper than two hundred feet (200) for steeply dipping seams, or deeper than fifteen (15) times the thickness of the seam or workings for gently dipping seams. These areas may be affected by subsidence. iii. High Coal Mine Hazard (CH): Areas with abandoned and improperly sealed mine openings and areas underlain by mine workings shallower than two hundred feet (200) in depth for steeply dipping seams, or shallower than fifteen (15) times the thickness of the seam or workings for gently dipping seams. These areas may be affected by collapse or other subsidence. According to the published geologic maps, there is not known mine workings on or within the immediate vicinity of the site. Therefore, the site has low coal mine hazard rating. WHHughes.NW24thSt.RG December 22, 2014 Page 6 Volcanic Hazards f. Volcanic Hazards: Volcanic hazard areas are those areas subject to a potential for inundation from post lahar sedimentation along the lower Green River as identified in Plate II, Map D, in the report U.S. Department of the Interior, U.S. Geological Survey (Revised 1998). Volcano Hazards from Mount Rainier, Washington. Open-File Report 98-428. According to the Volcano hazards from Mount Rainier, Washington by Hoblitt, R. P.; Wilder, J. S.; Driedger, C. L.; Scott, K. M.; Pringle, P. T.; Vallance, J. W. (USGS Open- File Report: 98-428, revised 1998) the site is not listed within the Lower White and Green River lahar floodways. CONCLUSIONS AND RECOMMENDATIONS Based on the soils encountered in our explorations, laboratory analyses, and our engineering analysis, it is our opinion that the construction of the proposed short plat is feasible from a geotechnical engineering standpoint. Site Preparation and Grading All structural areas on the site to be graded should be stripped of vegetation, organic surface soils, and other deleterious materials. Organic topsoil will not be suitable for use as structural fill, but may be used for limited depths in non-structural areas. Based on the encountered subsurface conditions, stripping depths range from 3 to 12 inches. Where placement of fill material is required, the stripped/exposed subgrade areas should be compacted to a firm and unyielding surface prior to placement of any fill. Excavations for debris removal should be backfilled with structural fill compacted to the densities described in the "Structural Fill" section of this report. The exposed subgrade soil should be proof-rolled with heavy rubber-tired equipment during dry weather or probed with a 1/2-inch-diameter steel rod during wet weather conditions. Any soft, loose or otherwise unsuitable areas delineated during proof- rolling or probing should be recompacted, if practical, or over-excavated and replaced with structural fill. Structural Fill Structural fill should be placed in horizontal lifts of appropriate thickness to allow adequate and uniform compaction of each lift. Fill should be compacted to at least 95 percent of MOD (maximum dry density as determined in accordance with ASTM D-1557). The appropriate lift thickness will depend on the fill characteristics and compaction equipment use, but is typically limited to 8 inches. The suitability of material for use as structural fill will depend on the gradation and moisture content of the soil. As the amount of fines (material passing US No. 200 sieve} increases, soil becomes increasingly sensitive to small changes in moisture content and adequate compaction becomes more difficult to achieve. During wet weather, we recommend use of well-graded sand and gravel with less than 5 percent (by weight) passing the US No. 200 sieve based on that fraction passing the 3/4-inch sieve, such as "Gravel Backfill for Walls' (9-03.12(2)). If prolonged dry weather prevails during the earthwork and foundation installation phase of construction, higher fines content (up to 10 to 12 percent) will be acceptable. Material placed for structural fill should be free of debris, organic matter, trash and cobbles greater than 6-inches in diameter. The moisture content of the fill material should be adjusted as necessary for proper compaction. WHHughes.NW24thSt.RG December 22, 2014 Page 7 Suitability of On-Site Materials as Fill During dry weather construction, any non-organic on-site soil may be considered for use as structural fill; provided it meets the criteria described above in the "Structural Fill" section and can be compacted as recommended. If the soil material is over-optimum in moisture content when excavated, it will be necessary to aerate or dry the soil prior to placement as structural fill. The native outwash sand has a low amount of fines content and will be suitable to use as fill during a wide range of moisture conditions. However, we do expect that the soil will become difficult to reuse as structural fill during extended periods of wet weather or when the soil is work at 3 percent or more above optimum moisture content. We recommend that completed graded-areas be restricted from traffic or protected prior to wet weather conditions. The graded areas may be protected by paving, placing asphalt-treated base, a layer of free-draining material such as pit run sand and gravel or clean crushed rock material containing less than 5 percent fines, or some combination of the above. Foundation Support Based on the subsurface soil conditions encountered in our test pits, we anticipate that the residences will be supported on the native outwash soils. We recommend a minimum width of 18 inches for isolated footings and at least 12 inches for single story or 16 inches multi-story structures for continuous wall footings. All footing elements should be embedded at least 18 inches below grade for frost protection. Footings founded as described above can be designed using an allowable soil bearing capacity of 2,000 psf (pounds per square foot) for combined dead and long-term live loads. The weight of the footing and any overlying backfill may be neglected. The allowable bearing value may be increased by one-third for transient loads such as those induced by seismic events or wind loads. Lateral loads may be resisted by friction on the base of footings and floor slabs and as passive pressure on the sides of footings. We recommend that an allowable coefficient of friction of 0.30 be used to calculate friction between the concrete and the underlying native outwash. Passive pressure may be determined using an allowable equivalent fluid density of 300 pct (pounds per cubic foot). Factors of safety have been applied to these values. We estimate that settlements of footings designed and constructed as recommended will be less than 1 inch, for the anticipated load conditions, with differential settlements between comparably loaded footings approach total settlements. Most of the settlements should occur essentially as loads are being applied. However, disturbance of the foundation subgrade during construction could result in larger settlements than predicted. We recommend that all foundations be provided with footing drains. Floor Slab Support Slab-on-grade floors, where constructed, should be supported on the native outwash or properly placed and compacted structural fill. We recommend that floor slabs be directly underlain by a minimum 4-inch thickness capillary break material such as pea gravel, or Gravel Backfill for Drains (WSDOT 9-03.1214). The capillary break material should be placed in one lift and compacted to an unyielding condition. A synthetic vapor barrier is recommended to control moisture migration through the slabs. This is of particular importance where the foundation elements are underlain by the silty till, or where moisture migration through the slab is an issue, such as where adhesives are used to anchor carpet or tile to the slab. WHHughes.NW24thSt.RG December 22, 2014 Page 9 We trust this is sufficient for your current needs. Should you have any questions, or require additional information, please contact us at your earliest convenience. Respectfully submitted, GeoResources, LLC KSS:DCB:kss Keith S. Schembs, LEG Principal DoclD: WHHughes.NW24thSt.RG Attachments: Figure 1: Site Vicinity Map Figure 2: Site and Exploration Map Figure 3: USDA Soil Map Figure 4: USGS Geologic Map Figure 5: Unified Soil Classification System Figure 5: Test Pit Logs Dana C. Biggerstaff, PE Senior Geotechnical Engineer N l1Sf$t i _.!.NE .x>ltt s-r _ -. "f"·--~--- ', _, 1' \ 1 I o~; ke Washington Approximate Site Location (map created from the King County iMap http://www5.kingcounty.gov/iMAP/) GeoResources, LLC 5007 Pacific Highway East, Suite 16 Fife, Washington 98424 Phone: 253-896-1 011 Fax: 253-896-2633 Site Location Map Proposed Short Plat NE 241h Street Renton, WA Job: WHHughes.NE24thSt.F Nov 2014 Not to Scare Figure 1 Approximate Site Location (map created from the King County iMap http://www5.kirgcounty.gov/iMAP/) GeoResources,LLC 5007 Pacific Highway East, Suite 16 Fife, Washington 98424 Phone: 253-896-1011 Fax: 253-896-2633 Site & Exploration Plan Proposed Short Plat NE 241h Street Renton, WA Job: WHHughes.NE24thSt.F Nov 2014 Not to Scare Figure 2 ApproximateSite Location (Soiis Map created fcom NRCS Web Soil Survey http://websoilsurvey.sc.egov.usda.gov) i Soil Soil Name Parent Material' i Tvpe --I lnC , L__~--- Indianola Loamy Sand Sandy Glacial Outw2sh GeoResources, LLC 5007 Pacific Highway East, Suite 16 Fife, Washington 98424 Phone: 253-896-1011 Fax: 253-896-2633 --------------------- Slopes I Erosion Hazard 6-15 I Moderate NRCS Soils Map Proposed Short Plat NE 241h Street Renton, WA Job: WHHughes.NE24thSt.F I Nov 2014 Hydrologic ! Soils Group i A I Not to Scale I Figure 3 ,, -·'. • ' ' {. ~' • • < ' • • < .. Qg.-:, Approximate Site Location (excerpt of the Washington Interactive Geologic Map https://fortress.wa.gov/dnr/geology/) D Qgo -Continental Glacial Outwash, Fraser Age GeoResources, LLC 5007 Pacific Highway East, Suite 16 Fife, Washington 98424 Phone: 253-896-1011 Fax: 253-896-2633 USGS Geologic Map Proposed Short Plat NE 24'h Street Renton, WA Job: WHHughes.NE24thSt.F Nov 2014 Not to Scale Figure 4 SOIL CLASSIFICATION SYSTEM MAJOR DIVISIONS GROUP GROUP NAME SYMBOL GRAVEL CLEAN GW WELL-GRADED GRAVEL, FINE TO COARSE GRAVEL GRAVEL COARSE GP POORLY-GRADED GRAVEL GRAINED More than 50% SOILS Of Coarse Fraction GRAVR GM SILTY GRAVEL Retained on No. 4Sieve WITH FINES GC CLAVEY GRAVEL More than 50% SAND ' CLEAN SAND SW WELL-GRADED SAND, FINE TO COARSE SAND Retained on No. 200 Sieve SP POORLY-GRADED SAND More than 50% Of Coarse Fraction SAND SM SILTY SAND Passes WITH FINES No. 4 Sieve SC CLAYEY SAND SILT AND CLAY INORGANIC ML SILT FINE GRAINED CL CLAY SOILS Liquid Lim it Less than 50 ORGANIC OL ORGANIC SILT, ORGANIC CLAY SILT AND CLAY INORGANIC MH SILT OF HIGH PLASTICITY, ELASTIC SILT More 1han 50% Passes CH CLAY OF HIGH PLASTICITY, FAT CLAY No. 200 Sieve Liquid Limit 50 or more ORGANIC OH ORGANIC CLAY, ORGANIC SILT HIGHLY ORGANIC SOILS PT PEAT NOTES: SOIL MOISTURE MODIFIERS: 1-Field classification is based on visual examination of soil in general accordance with ASTM D2488-90. Dry-Absence of moisture, dry to the touch Moist-Damp, but no visible water 2. Soil classification using laboratory tests is based on ASTM D2487-90. Wet-Visible free water or saturated, usually soil is obtained from below water table 3. Description of soil densi1y or consistency are based on interpretation of blow count data, visual appearance of soils, and Or test data. GeoResources, LLC Soil Classification System 5007 Pacific Highway East, Suite 16 Proposed Short Plat Fife, Washington 98424 NE 24'" Street Phone: 253-896-1 011 Renton, WA Fax: 253-896-2633 Job: WHHughes.NE24thSt.F I Nov 2014 I Figure 5 Depth (feet) 0 -Y:a Y:a -4Y2 4Yz -6Y:a 6Yz -7Y:a Depth (feet) 0 -Y:a 1 Y:a 1Y2 7 Depth (feet) 0 -% % -2 2 7 Depth (feet) 0 -14 \I, -1 Y2 1Yz -2 2 -3Y, 311, -7 Soil Type - SP SW SP Test Pit Log TP-1 Location: SW corner of eastern front lot Soil Description Sod over Topsoil Light orange brown fine to medium SAND with some silt to silty, trace roots (med dense, moist) Light brown coarse SAND, with some gravel (loose to med dense, moist) Light brown medium SAND with trace silt (med dense, moist) Test pit terminated at about 7 foot below existing grade. Slight caving observed from 4 to 6 ft, No groundwater seepage observed Test Pit Log TP-2 Location: SW corner of western front lot Soil Type Soil Description -Sod over Topsoil SP Light orange brown fine to medium SAND with som.e silt to silty, trace roots (med dense, moist) SP Light brown medium SAND with trace silt (med dense, moist) Soil Type SP SP Soil Type - SP - SP SP Test pit terminated at about 7 feet below existing grade. No caving observed, No groundwater seepage observed Test Pit Log TP-3 Location: South of fence, between two front lots Soil Description Sod over Topsoil Orange brown fine to medium SAND with trace to some silt, trace roots (med dense, moist) Light brown medium SAND with trace silt (med dense, moist) Test pit terminated at about 7 foot below existing grade. No caving observed, No groundwater seepage observed Test Pit Log TP-4 Location: North of gate to back third lot Soil Description Sod over Topsoil Orange brown fine to medium SAND with some silt to silty, trace roots (med dense, moist) Relict Topsoil Light orange brown fine to medium SAND with trace to some silt, trace roots (med dense, moist) Light brown medium SAND with trace silt (med dense, moist) Test pit terminated at about 7 feet below existing grade. No caving observed, No groundwater seepage observed Excavated on: Nov 24, 2014 Lonned bv: KSS GeoResources, LLC 5007 Pacific Highway East, Suite 16 Fife, Washington 98424 Phone: 253-896-1011 Fax: 253-896-2633 Test Pit Logs Proposed Short Plat NE 241h Street Renton, WA Job: WHHughes.NE24thSt.F I Nov 2014 I Figure 6 SECTION? OTHER PERMITS SECTION 8 ESC ANALYSIS AND DESIGN Encompass Engineering & Surveying Eastern Washington Di,:ision 407 Swiftwater Blvd., Cle Elum. WA 98922 Phone (509) 674-7433 Fax (509) 674-7419 Western Washington Division 165 NE Juniper St .• Suite 201, Issaquah, WA 98027 Phone (425) 382-0250 Fax (425) 391-3055 SHEET NO -----------OF ________ _ CALCULATED BY---------DATE -------- CHECKED BY __________ DATE-------- SCALE ---------------------- -'" --·~---. -"""' --. -· vezf}I) Tr!' IL-:. eat? zl{)/V SECTION 9 BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT Site Improvement Bond Quantity Worksheet S15 Web date: 04/03/2015 tQ King County Department of Permitting & Environmental Review 35030 SE Douglas Street, Suite 210 Snoqualmie, Washington 98065-9266 206-296-6600 TTY Relay 711 Project Name: NE 24th 3-Lot Short Plat Location: Clearing greater than or equal to 5,000 board feet of timber? ______ yes If yes, Forest Practice Permit Number: (RCW 76.09) Page 1 of9 _x __ no Site Improvement Bond Quantity Worksheet 2015.xls For alternate formats, call 206-296-6600. Date: 5/21/2015 Project No.: Activity No.: Note: All prices include labor, equipment, materials, overhead and profit Prices are from RS Means data adjusted for the Seattle area or from local sources if not included in the RS Means database. Unit prices updated: 3/2/2015 Version: 3/2/2015 Report Date: 5/21/2015 Site Improvement Bond Quantity Worksheet S15 Webdate: 0410312015 Reference# EROSION/SEDIMENT CONTROL Number Backfill & compaction-embankment ESC-1 Check dams, 4" minus rock ESC-2 SWDM 5.4.6.3 Crushed surfacing 1 1/4" minus ESC-3 WSDOT 9-03.9(3) Ditching ESC-4 Excavation-bulk ESC-5 Fence, silt ESC-6 SWDM 5.4.3.1 Fence, Temoorarv (NGPE) ESC-7 Hydroseeding ESC-8 SWDM 5.4.2.4 Jute Mesh ESC-9 SWDM 5.4.2.2 Mulch, by hand, straw, 3" deep ESC-10 SWDM 5.4.2.1 Mulch, by machine, straw, 2" deep ESC-11 SWDM 5.4.2.1 Piping, temporary, CPP, 6" ESC-12 Piping, temporary, CPP, 8" ESC-13 Piping, temporarv, CPP, 12" ESC-14 Plastic covering, 6mm thick, sandbaaned ESC-15 SWDM 5.4.2.3 Rip Rap, machine placed; slopes ESC-16 WSDOT 9-13.1(2) Rock Construction Entrance, 50'x15'x1' ESC-17 SWDM 5.4.4.1 Rock Construction Entrance, 100'x15'x1' ESC-18 SWDM 5.4.4.1 Sediment pond riser assembly ESC-19 SWDM 5.4.5.2 Sediment trap, 5' high berm ESC-20 SWDM 5.4.5.1 Sed. trap, 5' high, riprapped spillway berm section ESC-21 SWDM 5.4.5.1 Seedino, by hand ESC-22 SWDM 5.4.2.4 Sodding, 1" deep, level ground ESC-23 SWDM 5.4.2.5 Sodding, 1" deep, sloped ground ESC-24 SWDM 5.4.2.5 TESC Supervisor ESC-25 Water truck, dust control ESC-26 SWDM 5.4.7 WRITE-IN-ITEMS •••• lsee naae 91 Page 2 of 9 Site Improvement Bond Quantity Worksheet 2015.xls Unit Price Unit Quantity $ 6.00 CY $ 80.00 Each $ 95.00 CY $ 9.00 CY $ 2.00 CY 150 $ 1.50 LF $ 1.50 LF 470 $ 0.80 SY $ 3.50 SY $ 2.50 SY $ 2.00 SY 500 $ 12.00 LF $ 14.00 LF $ 18.00 LF $ 4.00 SY $ 45.00 CY $ 1,800.00 Each 1 $ 3,200.00 Each $ 2,200.00 Each $ 19.00 LF $ 70.00 LF $ 1.00 SY $ 8.00 SY $ 10.00 SY $ 110.00 HR $ 140.00 HR Each ESC SUBTOTAL: 30% CONTINGENCY & MOBILIZATION: ESCTOTAL: COLUMN: #of Applications Cost 1 300 1 705 1 1000 1 1800 $ 3,805.00 $ 1,141.50 $ 4,946.50 A Unit prices updated: 312/2015 Version: 3/2/2015 Report Date: 5/21/2015 Site Improvement Bond Quantity Worksheet .. Existing Future Public Right-of-Way Right of Way & Drainage Facilities Unit Price Unit Quant. Cost Quant. Cost Quant. GENERAL ITEMS No. Backfill & Compaction-embankment GI -1 $ 6.00 CY Backfill & Compaction-trench GI -2 $ 9.00 CY Clear/Remove Brush, by hand Gl-3 $ 1.00 SY Clearim:i/Grubbinq/Tree Removal Gl-4 $10,000.00 Acre Excavation -bulk GI -5 $ 2.00 CY Excavation -Trench GI -6 $ 5.00 CY Fencina, cedar, 6' hiah GI -7 $ 20.00 LF Fencina, chain link, vimd coated, 6' hiah GI -8 $ 20.00 LF Fencinq, chain link, Qate, vinvl coated, 2 GI -9 $ 1,400.00 Each Fencinq, solit rail, 3' hioh Gl-10 $ 15.00 LF Fill & comoact -common barrow GI -11 $ 25.00 CY Fill & comoact -aravel base GI -12 $ 27.00 CY Fill & comoact -screened topsoil GI -13 $ 39.00 CY Gabion, 12" deep, stone filled mesh GI· 14 $ 65.00 SY Gabion, 18" deeo, stone filled mesh GI -15 $ 90.00 SY Gabion, 36" deep, stone filled mesh GI-16 $ 150.00 SY Gradina, fine, bv hand Gl-17 $ 2.50 SY Gradina, fine, with arader GI -18 $ 2.00 SY Monuments, 3' Iona GI -19 $ 250.00 Each Sensitive Areas Sian GI· 20 $ 7.00 Each SoddinQ, 1" deeo, sloped oround Gl-21 $ 8.00 SY Survevina, line & orade GI -22 $ 850.00 Dav Survevina, lot location/lines GI· 23 $ 1,800.00 Acre 0.58 Traffic control crew f 2 flanners ) GI· 24 $ 120.00 HR Trail, 4" chipped wood GI -25 $ 8.00 SY Trail, 4" crushed cinder GI -26 $ 9.00 SY Trail, 4" top course GI -27 $ 12.00 SY Wall, retainino, concrete GI -28 $ 55.00 SF Wall, rockery G/-29 $ 15.00 SF Page 3 of 9 SUBTOTAL .. KCC 27A authorizes only one bond reduction. Site Improvement Bond Quantity Worksheet 2015.xls Web date: 04/03/2015 Private Improvements Casi 1,044.00 1,044.00 Unit prices updated 03/02/2015 Version: 03/02/2015 Report Date: 5/21/2015 Site Improvement Bond Quantity Worksheet Existing Future Public Right..af-way Right of Way & Drainaae Facilities Unit Price Unit Quant. I Cost Quant. I Cost Quant. ROAD IMPROVEMENT No. AC Grindina, 4' wide machine< 1000sv RI -1 $ 30.00 SY AC Grindina, 4' wide machine 1000-20001 RI -2 $ 16.00 SY AC Grindina, 4' wide machine > 20D0sy RI -3 $ 10.00 SY AC Removal/Disposal RI -4 $ 35.00 SY Barricade, tvne Ill (Permanent) RI -6 $ 56.00 LF Curb & Gutter, rolled RI -7 $ 17.00 LF Curb & Gutter, vertical RI -8 $ 12.50 LF 35 437.50 Curb and Gutter, demolition and disposal RI -9 $ 18.00 LF 35 630.00 Curb, extruded asphalt RI-10 $ 5.50 LF Curb, extruded concrete RI· 11 $ 7.00 LF Sawcut, asohalt, 3" depth RI-12 $ 1.85 LF 100 185.00 Sawcut, concrete, oer 1" depth RI -13 $ 3.00 LF Sealant, asahalt RI -14 $ 2.00 LF 100 200.00 Shoulder, AC, I see AC road unit price) RI -15 $ -SY Shoulder, aravel, 4" thick RI-16 $ 15.00 SY Sidewalk, 4" thick RI-17 $ 38.00 SY 30 1,140.00 Sidewalk, 4" thick, demolition and disoos: RI -18 $ 32.00 SY Sidewalk, 5" thick RI-19 $ 41.00 SY 30 1,230.00 Sidewalk, 5" thick, demolition and dispos, RI-20 $ 40.00 SY Sian, handicari RI-21 $ 85.00 Each Stripina, per stall RI -22 $ 7.00 Each Stripino, thermoplastic, ( for crosswalk ) RI -23 $ 3.00 SF Slriping, 4" reflectorized line RI -24 $ 0.50 LF Page 4 of 9 SUBTOTAL 3,822.50 *KCC 27A authorizes only one bond reduction. Site Improvement Bond Quantity Worksheet 2015.xls Web date: 04/03/201S Private Improvements -· Cost Unit prices updated: 03/02/2015 Version: 03/02/2015 Report Date: 5/21/2015 Site Improvement Bond Quantity Worksheet Web date: 04/03/2015 I Unit Price ROAD SURFACING No. Additional 2.5" Crushed SuriacinQ RS-1 $ 3.60 HMA 1/2" Overrav, 1.5" RS-2 $ 14.00 HMA 1 /2" Overrav 2" RS-3 $ 18.00 HMA Road, 2". 4" rock, First 2500 SY RS-4 $ 28.00 HMA Road, 2", 4" rock, Qty. over 2500 S' RS-5 $ 21.00 HMA Road, 3", 9 112" Rock, First 2500 S' RS-6 $ 35.00 HMA Road, 3", 9 112" Rock, Otv Over 251 RS-7 $ 42.00 Not Used RS-8 Not Used RS-9 HMA Road. 6" Oeoth, First2500 SY RS -10 $ 33.10 HMA Road, 6" Depth, Otv. Over 2500 SY RS -11 $ 30.00 HMA 3/4" or 1", 4" Depth RS-12 $ 20.00 Gravel Road, 4" rock, First 2500 SY RS-13 $ 15.00 Gravel Road, 4" rock, Qtv. over 2500 SY RS-14 $ 10.00 PCC Road (Add Under Write-Ins w/Desir RS-15 Thickened Edge RS -17 $ 8.60 Page 5 of9 SUBTOTAL "KCC 27 A authorizes only one bond reduction. Site Improvement Bond Quantity Worksheet 2015.xls Unit SY SY SY SY SY SY SY SY SY SY SY SY LF Existing Future Public Private Right•of.way Right of Way Improvements & Drainage Facilities Quant. Cost Quant. l Cost Quant. Cost (4" Rock -2.5 base & 1.5" to course 91/2" Rock-8" base & 1.5" too course\ 20 560.00 180 560.00 5,040.00 5,040.00 Unit prices updated: 03/02/2015 Version: 03/02/2015 Report Date: 5/2112015 Site Improvement Bond Quantity Worksheet Web date: 04/03/2015 I Unit Price Unit DRAINAGE (CPP = Corrugated Plastic Pipe, N12 or Equivalent) Access Road, R/0 D -1 $ 21.00 SY Bollards -fixed D-2 $ 240.74 Each Bollards -removable D-3 $ 452.34 Each * <CBs include frame and lid) CB Tvpe I D-4 $ 1,500.00 Each CB T""e IL D-5 $ 1,750.00 Each CB Tvne II, 48" diameter D-6 $ 2,300.00 Each for additional depth over 4' D-7 $ 480.00 FT CB Tune II, 54" diameter D-8 $ 2,500.00 Each for additional depth over 4' D-9 $ 495.00 FT CB Tvpe II, 60" diameter 0-10 $ 2,800.00 Each for additional depth over 4' 0 -11 $ 600.00 FT CB Type II, 72" diameter 0-12 $ 3,600.00 Each for additional depth over 4' 0-13 $ 850.00 FT Throuah-curb Inlet Framework (Add) 0 -14 $ 400.00 Each Cleanout, PVC, 4" D-15 $ 150.00 Each Cleanout, PVC, 6" D-16 $ 170.00 Each Cleanout, PVC, 8" 0-17 $ 200.00 Each Culvert, PVC, 4" D-18 $ 10.00 LF Culvert, PVC, 6" 0-19 $ 13.00 LF Culvert, PVC, 8" 0-20 $ 15.00 LF Culvert, PVC, 12" D-21 $ 23.00 LF Culvert, CMP, 8" D -22 $ 19.00 LF Culvert, CMP, 12" D-23 $ 29.00 LF Culvert, CMP, 15" D-24 $ 35.00 LF Culvert, CMP, 18" D-25 $ 41.00 LF Culvert, CMP, 24" D • 26 $ 56.00 LF Culvert, CMP, 30" D-27 $ 78.00 LF Culvert, CMP, 36" D-28 $ 130.00 LF Culvert, CMP, 48 1 ' D -29 $ 190.00 LF Culvert, CMP, 60" D -30 $ 270.00 LF Culvert, CMP, 72" D -31 $ 350.00 LF Page6 of9 SUBTOTAL '*KCC 27A authorizes only one bond reduction. Site Improvement Bond Quantity Worksheet 2015.xls Existing Future Public Private Right-of-way Right of Way Improvements & Drainaae Facilities Quant. I Cost Quant. I Cost Quant. I Cos! For Culvert prices, Averaae of 4' cover was assumed. Assume perforated PVC is same orice as solid oioe. 3 1 138 . ' 4,500.00 170.00 2,070.00 6,740.00 Unit prices updated: 03102/2015 Version: 03/02/2015 Report Date: 5121 /2015 Site Improvement Bond Quantity Worksheet Existing Future Public Right.of-way Right of Way DRAINAGE CONTINUED & Drainage Facilities No. Unit Price Unit Quant Cost Quant. Cost Quant. Culvert, Concrete, 8" D-32 $ 25.00 LF Culvert, Concrete, 12" D-33 $ 36.00 LF Culvert, Concrete, 15" D-34 $ 42.00 LF Culvert, Concrete, 18" D-35 $ 48.00 LF Culvert, Concrete, 24" D-36 $ 78.00 LF Culvert, Concrete, 30" D-37 $ 125.00 LF Culvert, Concrete, 36H D-38 $ 150.00 LF Culvert, Concrete, 42" D-39 $ 175.00 LF Culvert, Concrete, 48" 0-40 $ 205.00 LF Culvert, CPP, 6" 0-41 s 14.00 LF Culvert, CPP, 8" 0-42 $ 16.00 LF Culvert, CPP, 12" 0-43 $ 24.00 LF Culvert, CPP, 15" 0-44 $ 35.00 LF Culvert, CPP, 18" 0-45 $ 41.00 LF Culvert, CPP, 24" 0-46 $ 56.00 LF Culvert, CPP, 30" 0-47 $ 78.00 LF Culvert, CPP, 36" 0-48 $ 130.00 LF Ditchina 0-49 s 9.50 CY Flow Dispersal Trench (1,436 base+) D-50 $ 28.00 LF French Drain /3' depth) D-51 $ 26.00 LF Geotextile, laid in trench, oolvpropvlene D-52 $ 3.00 SY Mid-tank Access Riser, 48" dia, 6' deep 0-54 $ 2,000.00 Each Pond Overflow Spillwav D-55 $ 16.00 SY Restrictor/Oil Separator, 12" D-56 $ 1,150.00 Each Restrictor/Oil Separator, 15" D-57 $ 1,350.00 Each Restrictor/Oil Separator, 18" D-58 $ 1,700.00 Each Riorap, placed D-59 $ 42.00 CY Tank End Reducer (36" diamelerl D-60 $ 1,200.00 Each Trash Rack, 12" D-61 $ 350.00 Each Trash Rack, 15" D-62 $ 410.00 Each Trash Rack, 18" D-63 $ 480.00 Each Trash Rack, 21" D-64 $ 550.00 Each Page 7 of9 SUBTOTAL *KCC 27A authorizes only one bond reduction. Site Improvement Bond Quantity Worksheet 2015.xls Web date· 04/03/2015 Private Improvements Cost Unit prices updated: 03/02/2015 Version: 03/02/2015 Report Date: 5/2112015 Site Improvement Bond Quantity Worksheet Web date: 04/03/2015 I Unil Price Unit PARKING LOT SURFACING No. 2" AC, 2" too course rock & 4" borrow PL-1 $ 21.00 SY 2" AC, 1.5" too course & 2.5" base coun PL -2 $ 28.00 SY 4" select borrow PL -3 $ 5.00 SY 1.5" too course rock & 2.5" base course PL-4 $ 14.00 SY UTILITY POLES & STREET LIGHTING Utilitv Pole(s) Relocation I UP-1 Lump Sum Street Licht Poles w/Luminaires I UP-2 Each WRITE-IN-ITEMS (Such as detention/water qualitv vaults.) No. Relocated Street Licht Wl-1 $ 2,500.00 Each Wl-2 SY Wl-3 CY Infiltration Trench Wl-4 $ 50.00 LF Wl-5 FT Wl-6 Wl-7 Wl-8 Wl-9 Wl-10 SUBTOTAL SUBTOTAL (SUM ALL PAGES): 30% CONTINGENCY & MOBILIZATION: GRANDTOTAL: COLUMN: Page 8 of9 *KCC 27 A authorizes only one bond reduction. Site Improvement Bond Quantity Worksheet 2015,xls Existing Future Public Private Right-of-way Right of Way Improvements & Drainaae Facilities Quant. Price Quant. I Cost Quanl. Cost Not To Be Used For Roads Or Shoulders NA NA NA NA NA NA NA NA Utility pole relocation costs must be accompanied bv Franchise Utility's Cost Estimate 1 2500 2,500.00 6,882.50 2,064.75 8,947.25 B C 23 1,150.00 1,150.00 13.974.00 4.192.20 18,166.20 D Unit prices updated: 03/02/2015 Version: 03/02/2015 Report Date: 5/21/2015 Site Improvement Bond Quantity Worksheet 01/12/15 Original bond computations prepared by: Name:------------------------------------- PE Registration Number: ------------------------------ Firm Name: ----------------------------------- Address: £ ,2;,., lt>-r I Date: Tel#: ------------ Project#: ROAD IMPROVEMENTS & DRAINAGE FACILITIES FINANCIAL GUARANTEE REQUIREMENTS Stabilization/Erosion Sediment Control (ESC) Existing Right-of-Way lmprovments Future Public Right-of-Way Drainage Facilities (Pond/Bioswale/Vaults,etc) Private Improvements Calculated Quantity Completed Total Right-of-Way and/or Site Restoration PERFORMANCE BOND* AMOUNT (A) $ 4tS4{6. f;O (B) $ ~, • '2 t; (C,) $ (C,) $.----- (D) s ,a.,Gt.zo (A+B) S /3.B'J~. 7~ Performance Bond* Amount (A+B+C,)xl.5 = Total l(T) $ 20, e,'lo , G3 Maintenance/Defect Bond* Total BOND* AMOUNT REQUIRED AT RECORDING OR TEMP OCCUPANCY*** NAME OF PERSON PREPARING BOND* REDUCTION: ------------------- "'NOTE: The word "Bond" as used in this document means a financial guarantee acceptable to the City of Renton. **NOTE: Right-of-way and site restoration bonds to be combined when both are required. PUBLIC ROAD & DRAINAGE MAINTENANCE/DEFECT BOND* (B+C+Public Portion of C,) x 0.2 =$ ______ _ DATE: -------- The restoration requirement shall include the total cost for all TESC as a minimum, not a maximum. In addition, corrective work, both on-and off-site needs to be included. Quantities shall reflect worse case scenarios, not just minimum requirements. For example, if a salmon id stream may be damaged, some estimated costs for restoration needs to be reflected in this amount. Required Bond* Amounts Are Subject to Review ond Modifications by COR. - l SECTION 10 OPERATIONS AND MAINTENANCE MANUAL C.2.2.6 MAINTENANCE INSTRUCTIONS FOR FULL INFILTRATION If the full infiltration flow control BMP is proposed for a project, the following 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.1.3.3 (p. C-18). 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; DDES may require additional instructions based on site- specific conditions. Also, as the County gains more experience with the maintenance and operation of these BMPs, future updates to the instructions will be posted on King County's Surface Water Design Manual website. Q TEXT OF INSTRUCTIONS Your property contains a stormwater management flow control BMP (best management practice) called "full infiltration," which was installed to mitigate the stormwater quantity and quality impacts of some or all of the impervious surfaces on your property. Full infiltration is a method of soaking runoff from impervious area (such as paved areas and roofs) into the ground. If properly installed and maintained, full infiltration can manage runoff so that a majority of precipitation events are absorbed. Infiltration devices, such as gravel filled trenches, drywells, and ground surface depressions, facilitate this process by putting runoff in direct contact with the soil and holding the runoff long enough to soak most of it into the ground. To be successful, the soil condition around the infiltration device must be reliably able to soak water into the ground for a reasonable number of years. The infiltration devices used on your property include the following as indicated on the flow control BMP site plan: D gravel filled trenches, D drywells, 0 ground surface depressions. The size, placement, and composition of these devices as depicted by the flow control BMP site plan and design details must be maintained and may not be changed without written approval either from the King County Water and Land Resources Division or through a future development permit from King County. Infiltration devices must be inspected annually and after major storm events to identify and repair any physical defects. Maintenance and operation of the system should focus on ensuring the system's viability by preventing sediment-laden flows from entering the device. Excessive sedimentation will result in a plugged or non-functioning facility. If the infiltration device has a catch basin, sediment accumulation must be removed on a yearly basis or more frequently if necessary. Prolonged ponding around or atop a device may indicate a plugged facility. If the device becomes plugged, it must be replaced. Keeping the areas that drain to infiltration devices well swept and clean will enhance the longevity of these devices. ~or roofs, frequent cleaning of gutters will reduce sediment loads to these devices. 11 En~eQlTIJ?~.?S V TECHNICAL INFORMATION REPORT for NE 24'h 3-Lot Short Plat LUA14-001654, SHPL-A O" April 6, 2015 '-.• ~ '\'.evised 4/24/15 ""L, Revised 5/13/15 f> Encompass Engineering Joh No. 14690 Prepared For Bill Hughes 14401 Issaquah-Hobart RD Issaquah, WA 98027 Western Washington Division 165 NE Juniper St., Ste 20 I, Issaquah, WA 98027 Phone: (425) 392-0250 Fax: (425) 391-3055 www.EncompassES.net Eastern Washington Division 108 East 2"' Street, Cle Elum, WA 98922 Phone: (509) 674-7433 Fax: (509) 674-74 l 9 TABLE OF CONTENTS SECTION I: PROJECT OVERVIEW SECTION II: CONDITIONS AND REQUIREMENTS SUMMARY SECTION III: OFF-SITE ANALYSIS SECTION IV: FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN SECTION V: CONVEYANCE SYSTEM ANALYSIS AND DESIGN SECTION VI: SPECIAL REPORTS AND STUDIES SECTION VII: OTHER PERMITS SECTION VIII: ESC ANALYSIS AND DESIGN SECTION IX: BOND QUANTITIES, FACILITY SUMMARIES, AND ; DECLARATION OF COVENANT SECTION X: OPERATIONS AND MAINTENANCE MANUAL -. SECTION 1 PROJECT OVERVIEW Site Address: King County Tax Parcels: Project Overview 24XX NE 24th St., Renton, WA 98059 813210-0120 and 813210-0130 This project involves the development of two vacant parcels totaling 0.58 acres into three single- family lots in the Kennydale area. These parcels are located within Northeast Section 05, Township 23 North, Range 5 East, W.M. The existing topography of these parcels generally slopes down to northwest at approximately I0%to 25%. The existing parcels are vacant and is covered with lawn and several mature trees. Per the USDA Web Soil Survey, the site is underlain with Indianola fine to medium sand. -Refer to Sec. 6 of this TIR for geotech report and infiltration test results prepared by Geo Resources. Proposed Drainage Controls Stormwater will be controlled on the joint driveway with the plat infrastructure construction and in the future with individual lot infiltration trenches, to be constructed with future residential building permits. A design in included in this TIR including a detail of the infiltration trench and a linear feet callout for each 1,000 sq-ft of impervious surface to be constructed. 2009 KC (Renton) SWDM Core Requirements Section 1.2.1 Core Requirement #1: Discharge at the natural location The site drainage will continue to infiltrate into the ground. Section 1.2.2 Core Requirement #2: Offsite Analysis An offsite drainage analysis is provided in this Preliminary TIR. Section 1.2.3 Core Requirement #3: Flow Control Individual infiltration trenches will be used on each lot for flow control. Section 1.2.4 Core Requirement #4: Conveyance System The conveyance analysis will be provide in the final TIR as needed. Section 1.2.5 Core Requirement #5: Erosion and Sediment Control A temporary erosion control plan will provide BMP's to be implemented during construction. Section 1.2.6 Core Requirement #6: Maintenance and Operations A maintenance and operations manual is in the TIR for int onsite infiltration. Section 1.2. 7 Core Requirement #7: Financial Guarantees and Liability The developer will arrange for any financial guarantees and liabilities required by the permit. Section 1.2.8 Core Requirement #8: Water Quality Because there will be less than 5,000 sq-ft of PGIS, water quality measures will not be needed. 2009 KC SWDM Special Requirements Section 1.3.1 NIA Special Requirement #1: Other Adopted Area-Specific Requirements Section 1.3 .2 Special Requirement #2: Floodplain/Floodway Delineation NI A there are no FEMA floodplains/floodways in the area Section 1.3.3 Special Requirement #3: Flood Protection Facilities NIA Section 1.3.4 Special Requirement #4: Source Control Source control is not required for this SFR project. Section 1.3 .5 Special Requirement #5: Oil Control Oil control is not required for this SFR project. Section 1.3.6 Special Requirement #6: Aquifer Protection Area Even though the project in in APA Zone 2, because ther.e will be less than 5,000 sq-ft of PGIS, liners or or other restrictions relating to soil meeting max/min infiltration rates and/or cation exchange criteria do not apply that might for a larger project. ~Alff"Illl!E REPLACE 1REES -(6} 2" CALIPER DECIDUOUS OR 5• HIGH CONIFER TREES REQUIRED PLAT OF SUriSET HILLS \IOL 169, PC 52 LOT ,1 • L l'H 3210-0110 EX. 5• CYCLONE fENCE 1830 NE 2TH sr APPROX LOCATlON Dt SEl'£R SlUB EX. GUR8/5' SIIJEWALK/6.5" PLAN"!ER STA!P 70 REMA!N EX CB RIM-285.72 INV•283.72 (8"PVC-N£) INV-.282.02 (B"AOS-S) I E:x. "NATER .\tETER CUR 1S30 ;I£ 24TH ST w ex ORI\CWAY EX srORM IMJ'4HOLE RjM,,,286.45 11'4V,.280.85 (1rAOS-E) ~2B~'i'Q_ -----so --s --s I ~ • ~ . ·-· ......... , ....... ' --· ............ ·-. -·. a ~ 10 w BIJ:010-0100 LOI 10 / / I 8(. 23X / / "'"'" / / )"-// " / /" "' ,,I, / / 'v / • • 9"07:ZO''w 48.00' / APPROX. LOCATION OF cU1tJRE LOT 2/3 3" \WlE INFlLlRATION lRENCHES (14.+ LF TAENCH/1.000 SO. FT. IMPERVIOUS \SURf"ACE) -NO Flll All.OWEO IN THESE AREAS \ 'L B1J2l0-Q<4Q Ex. s· WOOD FENCE LOT , ~ ,_ -162.,g· i +---- 1, LOT 3 V \ i 9.6tcr SO. FT TUNE LOT IJ r'I H ,mw-mw / ,i 111 LOT 1 7.02J so. FT. I, I 1,' -'-t-lOCJ'-6" PVC O 2.00:C I -SEE: C.O.R STI). PLAN 405 ,~ I.;; FCF: BEDDING SPECS. I ~ I ~ I~ .... r '° I' ~ ' I ' 21: ,.'.!'i ro· PRIVATE I . i ~,: """l' r [AS[MENT I ?,:: 2-5' ORAJNAGE ] 15? --4-J :Egn~~~E~~~~~~ rw I ' 1) 11 APPRO LOCATION : ~ r EX. 8" 0 PER CITY RECORDS I "' I 10" ELECTRIC EASEMENT , -R~ N~ 9~02~2:_ 1+: NEW DRl'JEWAY 's'6 8 • SO I --1-L..,,',!, 5 ' I-2.5' ORAINAGE & unun EA MENT I REC. NO. 946 19n, W. 1 ~OUT iE-264.96±: 10' IUnLITY EASEMENT REcJ ~ ~~977 l APPROX. LOCATION EX. SEWER STIJB -SA"M)JT AND RESTORE F'A\E'MENT PER C.O.R. SIDS R 3J4J90-2281 CBI 1, TYPE J W/ D0WNTURNED ELBOWS (ALL P RIIF.301.50 INV•298.00 (OVERFLOW) \NV..297.-nli {fNFlLTRATION UNE) 3: __l_____ APPROX. LOCA nON OF ' EX. 8" WATER !6" JOINT !-+-----,~-~:~ss{;~~~~ FDR LOT 2\3 ACCESS ex ORIVEWAY REPLACE SIC m NEW ORJI -SEE OETII.!. WATER MANHOL Fm,,j~JOl.4-7 TOP OF VALVE~ INV,.297.47 (12 EX. STORM MANliOLE RIMaa."lo2.09 INV•298.99 (T2"A0S-E&w EX. STORM M RIM=JOJ.05 lrW-291.JS ( Pl.AT CF STONE CASTLE VOL 200. PGS S9-61 LOT 27 r L ll0i955-0270 INV,,,291.Jl (1 fl 8( Site Plan 1" = 40' I I R-8 R-1 ZONING MAP BOOK PLANNING -TECHNICAL SERVICES PRINTED DATE: 10/02/2013 This do::umenl is a graphic represmtation, not !J.lil"anteed to survey accuracy, 1r1d is based en the bes1 infonnaticn availatie as of the date shown. This map is intended fa aty dsplay mroosesonlv. Community & Economic Development C4E 32 T24N R5E E 112 RC RC R-1 R-8 - RC R-8 Vicinity Map E4E 08 T23N R5E E 1/2 0 420 r-._-----840 I Fe! D4E 1:B,780 05 T2JN RSE E 112 Page12ofB0 City Limii:15 D iCORJ Commercial/Office/Residential O (R-4) Residential 4du.l.ac CJ RENTOO D (CV) CEtnter Vl~ll!le D {R-8) ResidenHa! Bdu/ac CPoten!/a/ Aooexafo1 Area CJ (IH) Industrial Heavy D (RC) Resairt!! Conserva1ion Zoning Designathrn D (IL} lnd:isbfal light O (RM-F} Residential Multi-Family D (CA) Commen::ia/Al1erial D OMJ Industrial Medium D (RM-T) Resi. Multi-Family Tradifonil D (GD) Center OownfDwn D {R-1) Re9idenUal 1du/ac D (RM-UJ Resi. Mull.i-F$1Jly Urba, Center CJ (CN) Comrnercfal/lleighbortJood D (R-10) Resident/at 10dulac O (RP.ti) Residential Manufactufl!d Homes D (CO) Commercial Offoo D (R-14) RllsldentiaJ 14du/ae D (UC-N1) Urba:i Center North 1 D {UC-N2) Urban Center North 2 N t SECTION 2 CONDITIONS AND REQUIREMENTS SUMMARY DEPARTMENT OF COMMUNITY AND ECONOMIC DEVELOPMENT City of ADMINISTRATIVE SHORT PLAT REPORT & DECISION A. SUMMARY AND PURPOSE OF REQUEST REPORT DATE: Project Name: Project Number: Project Manager: Owner: Applicant: Contact: Project Location: Project Summary: Exist. Bldg. Area SF: Site Area: March 6, 2015 NE 24th Street Short Plat LUA14-001654, SHPL-A Jill Ding, Senior Planner John Cowan, 1830 NE 24 1h Street, Renton, WA 98056 Bill Hughes, 14401 Issaquah-Hobart Road, Issaquah, WA 98027 Tom Redding, Encompass Engineering & Surveying, 165 NE Juniper Street, Suite 201, Issaquah, WA 98027 1904 and 1908 NE 24th Street Subdivision of an existing 2S,400 square foot (0.58 acre) project site zoned R-8 (Residential-8 dwelling units per acre) into three lots for the future construction of three single family residences. The project site consists of two vacant parcels on the north side of NE 24th Street (parcel nos. 8132100120 and 8132100130). An 18-foot wide private driveway is proposed on the eastern portion of proposed Lot 2 to provide access to proposed Lot 3. A variance was requested from the Fire Dept. to reduce the paving width required for the private driveway access to Lot 3 from 20 feet to 16 feet. Access to Lots 1 and 2 would be provided via residential driveways off of NE 24th Street. A street modification request has been submitted to allow the existing frontage improvements to remain along NE 24th Street. Sensitive slopes (grades between 25 and 40 percent), high landslide hazard areas, moderate landslide hazard areas, and Aquifer Protection Area 2 are mapped on the project site. N/A Proposed New Bldg. Area (footprint}: Proposed New Bldg. Area (gross}: Total Building Area GSF: Unknown N/A N/A -----------~ SHPL Report 14-001654 v2 City of Renton Deportment of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision LUA14-001654, SH PL-A Report of Marcil 6, 2015 Page 2 of 21 B. EXHIBITS: Short Plat Report Exhibit A.1: Staff Report Exhibit A.2: Neighborhood Detail Map Exhibit A.3: Short Plat Plan (dated December 24, 2014) Exhibit A.4: Conceptual Drainage Control, Generalized Utility and Grading Plan (dated December 15, 2014) Exhibit A.5: landscape Plan (dated December 2014) Exhibit A.6: Tree Cutting/land Clearing Plan (December 15, 2014) Exhibit A.7: Tree Retention Worksheet Exhibit A.8: Geotechnical Engineering Report, prepared by GeoResources, llC (dated 12/22/2014) Exhibit A.9: Preliminary Technical Information Report, prepared by Encompass Engineering & Surveying, dated December 29, 2014 Exhibit A.10: Street Modification Request Exhibit A.11: Street Modification Approval letter C. GENERAL INFORMATION: 1. Owner(s) of Record: John Cowan 1830 NE 24th Street Renton, WA 98056 2. Zoning Designation: Residential -8 dwelling units per acre (R-8) 3. Comprehensive Plan Land Use Designation: Residential Single Family (RSF) 4. Existing Site Use: Vacant 5. Neighborhood Characteristics: a. North: Single-family residential (R-8) b. East: Single-family residential (R-8) c. South: Single{amily residential (R-8} d. West: Single-family residential (R-8} 6. Access; NE 24th Street 7. Site Area: 25,400 sf D. HISTORICAL/BACKGROUND: Action Comprehensive Plan SHPL Reoort 14-001654 vz land Use File No. N/A Ordinance No. 5100 Date 11/01/2004 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Report of March 6, 2015 Zoning Annexation Interim Zoning N/A N/A N/A E. APPLICABLE SECTIONS OF THE RENTON MUNICIPAL CODE: 1. Chapter 2 Land Use Districts 5099 1818 5724 a. Section 4-2-020: Purpose and Intent of Zoning Districts b. Section 4-2-070: Zoning Use Table c. Section 4-2-110: Residential Development Standards d. Section 4-2-115: Residential Design and Open Space Standard 2. Chapter 3 Environmental Regulations and Overlay Districts a. Section 4-3-050: Critica I Area Regulations 3. Chapter 4 Property Development Standards a. Section 4-4-030: Development Guidelines and Regulations b. Section 4-4-070: Landscaping c. Section 4-4-130: Tree Retention and Land Clearing Regulations 4. Chapter 6 Streets and Utility Standards a. Section 4-6-060: Street Standards 5. Chapter 7 Subdivision Regulations a. Section 4-7-070: Detailed Procedures for Short Subdivisions Page 3 of 21 11/01/2004 03/17/1960 09/22/2014 b. Section 4-7-120: Compatibility with Existing Land Use and Plan -General Requirements and Minimum Standards c. Section 4-7-150: Streets -General Requirements and Minimum Standards d. Section 4-7-170: Residential Lots -General Requirements and Minimum Standards 5. Chapter 11 Definitions F. APPLICABLE SECTIONS OF THE COMPREHENSIVE PLAN: 1. Land Use Element: Residential Single Family 2. Community Design Element: Established Residential Neighborhoods and New and Infill Development G. DEPARTMENT ANALYSIS: 1. Project Description/Background The applicant has proposed to subdivide a 0.58 acre (25,400 square foot) site located within the Residential -8 dwelling units per acre (R-8) zone. The proposal would create 3 lots intended for the development of detached single-family residences. The project site is currently vacant. After the deduction of the 1,763 square foot private access easement, the proposal for 3 lots on the project site would result in a net density of 5.6 dwelling units per acre. Proposed Lot 1 would total 7,023 square feet in area, Lot 2 would total 7,004 square feet in area, and Lot 3 would total 9,610 square feet in area. SHPL l/epo1t 14-001654 v2 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plat Report & Decision WA14-001654, SHPL-A Page 4 of 21 City Council adopted Ordinance 5724 to provide interim zoning standards for the R-8 zone. The legislation and interim standards became effective at the time of Council approval on September 22, 2014, The NE 24th Street Short Plat application was determined a complete application on January 8, 2015, after the adopted of the interim zoning standards, and therefore, is vested to the interim zoning standards (Ordinance 5724) as well as the standards adopted under Ordinance 5702. Access for Lots 1 and 2 would be provided via new driveways off of NE 24th Street. Access to Lot 3 is proposed via a 16-foot wide private access easement over the east side of Lot 2. Existing frontage improvements, including paving, curb and gutter, landscaping, and sidewalks exist along the project site's NE 24th Street frontage. A street modification request was submitted with the short plat application to allow the existing frontage improvements to remain. Sensitive slopes (slopes with grades between 25 percent and 40 percent) and a high landslide hazard area are mapped on the project site. The existing ground surface generally slopes to the northwest with an elevation change of approximately 30 feet. A total of 7 significant trees have been identified on the project site and of these trees, 2 are proposed to be retained. The trees proposed for retention are located on the southwest corner of Lot 1 and the southeast corner of Lot 2. 2. Environmental Review Except when located on lands covered by water or sensitive areas, short plats are exempt from SEPA Environmental Review pursuant to WAC 197-11-800(6)(a). 3. Compliance with ERC Conditions N/A 4. Staff Review Comments Representatives from various city departments have reviewed the application materials to identify and address issues raised by the proposed development. These comments are contained in the official file, and the essence of the comments have been incorporated into the appropriate sections of this report and the Departmental Recommendation at the end of this report. 4. Consistency with Short Plat Criteria SHORT PLAT REVIEW CRITERIA: Approval of a short plat is based upon several factors. The following short plat criteria have been established to assist decision-makers in the review of the plat. (" Compliant; Note 1: Partially compliant; Note 2: Not compliant; Note 3: Compliance not yet demonstrated) r;J...IP/ RPnnrt 1,1-nnu~c;.1 11? City of Renton Depa11ment of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision LUA14-001654, SHPL-A - Report of March 6, 2015 Page 5 of 21 1. CONFORMANCE WITH THE COMPREHENSIVE PLAN: The site has the Comprehensive Land Use designation of Residential Single Family (RSF). Land designated RSF is intended to be used for high quality detached, single-family residential development organized into neighborhoods at urban densities. It is intended that larger subdivisions, infill development, and rehabilitation of existing housing be carefully designed to enhance and improve the quality of single family living environments. The proposal is consistent with the following Comprehensive Plan Land Use and Community Design Element policies, if all conditions of approval are met, unless noted otherwise: ./ Policy LU-158. Net development densities should fall within a range of 4.0 to 8.0 dwelling units per acre in Residential Single Family Neighborhoods . ./ Policy CD-14. Infill development, defined as new short plats of nine or fewer lots, should be encouraged in order to add variety, updated housing stock, and new vitality to neighborhoods . ./ Policy CD-15. Infill development should be reflective of the existing character of established neighborhoods even when designed using different architectural styles, and/or responding to more urban setbacks, height or lot requirements. Infill development should draw on elements of existing development such as placement of structures, vegetation, and location of entries and walkways, to reflect the site planning and scale of existing areas. 2. COMPLIANCE WITH THE UNDERLYING ZONING DESIGNATION: Objectives and policies of the Comprehensive Land Use Plan RSF designation are implemented by Residential 8 zoning (R-8). RMC 4-2-llOA provides development standards for development within the R-8 zoning classification. The proposal is consistent with the following development standards if all conditions of approval are met, unless noted otherwise: ./ Density: The allowed density range in the R-8 zone is a minimum of 4.0 to a maximum of 8.0 dwelling units per acre. Net density is calculated after the deduction of sensitive areas, areas intended for public right-of-way, and private access easements. Staff Comment: For the purposes of calculating net density the 1,763 square foot private access easement is required to be deducted from the gross site area of 25,400 square feet, resulting in a net area of 23,637 square feet (O.S4 acres). Based an the proposal far 3 lots, the net density would be 5. 6 dwelling units per net acre, which is within the allowed density range far the R-8 zone . ./ Lot Dimensions: Proposed Lots Lot Size Width Depth 7,000 SF minimum 60 feet minimum 90 feet minimum (70 feet for corner Jots) Lot 1 7,023 sf 71.50 feet 99.24 feet Lot 2 7,004 sf 91.12 feet 96.24 feet Lot 3 9,610 sf 60.00 feet 162.62 feet Note 3 Setbacks: The required setbacks in the R-8 zone per the Interim Zoning Ordinance 5724 are as follows: front yard is 25 feet, side yard (or shared driveway) is 7.5 feet, side yard SHPL Report 14-001654 v2 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plat Re part & Decision LUA14-001654, SHPL-A Page 6 of 21 along the street or access easement is 17.5 feet and the rear yard is 25 feet. Staff Comment: A 16-foot wide private access easement is proposed along the eastern side of Lot 2 to provide access to Lot 3. The front yard areas of proposed Lots 1 and 2 would be oriented to the south towards NE 24th Street; the front yard of Lot 3 would be oriented to the east. As proposed the new lots would provide adequate area for compliance with the required setbacks. Setbacks would be verified at the time of building permit review. Note 3 Building Standards: The Interim R-8 zoning requirements, per Ordinance 5724, for maximum building height is 30 feet. The maximum building coverage is 40 percent. Staff Comment: Building height and lot coverage for the new single family residences would be verified at the time of building permit review. Note 1 Landscaping: The City's landscape regulations (RMC 4-4-070) require all short plats to provide a 10-foot landscape strip along all public street frontages. Additional 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, are to be located in this area when present. Spacing standards shall be as stipulated by the Department of Community and Economic Development, provided there shall be a minimum of one street tree planted per address. Any additional undeveloped right-of-way areas shall be landscaped unless otherwise determined by the Administrator. Where there is insufficient right-of-way space or no public frontage, street trees are required in the front yard subject to approval of the Administrator. A minimum of two trees are to be located in the front yard prior to final inspection. Staff Comment: A conceptual landscape plan (Exhibit A.5} was submitted as part of the proposed land use application. The conceptual landscape plan (Exhibit A.5} shows a 10- foot wide landscaped strip along NE 24th Street. A planting detail was included showing 3 Western Red Cedar trees, 5 Vine Maple trees, Dayli/ies, Hans a Japanese Rose, Sword Fern, Pacific Wax Myrtle, Variegated Dogwood, Dwarf Muga Pine, Maiden Grass, and Kinnickinnick. A street modifkation request (Exhibit A.10} was submitted with the short pfat application allowing the applicant to retain the existing 6.5-foot landscape strip between the curb and sidewalk. The existing 6.5-foot landscape strip has 4 street trees. Due to the proposed locations af the driveways for the new lots, the applicant is proposing to replace or relocate 3 of the existing street trees (one tree would remain in its current location}. If the driveway curb cut for Lot 2 was consolidated with the proposed access easement to the west (providing access to Lot 3) anly 1 existing street tree would need to be relocated or replaced (see further discussion below under access}. To ensure retention of the existing mature street trees, staff recommends o condition of approval that o minimum of two existing street trees are retained. No trees were proposed within the front yard area of new Lot 3. Staff recommends, as o condition of opprova, that a detailed landscape plan be submitted at the time of Construction Permit application for review and approval by the Current Planning Project Manager. The de toiled landscape plan shall include two trees within the front yard area of Lot 3 and show the relocation or replacement of one street tree along NE 24'h Street. SHPL Rennrt 14-nn1r;c;4. 1,J City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plat Report & Decision LUA14-00l654, SHPL-A Page 7 of 21 The 10-foot landscaped strip and street trees shall be installed prior to final short plat approval and the street/front yard trees shall be installed prior to final building inspection . ./" Tree Retention: The City's adopted Tree Retention and Land Clearing Regulations require the retention of 30 percent of trees in a residential development. Staff Comment: A Tree Cutting/Land Clearing Plan (Exhibit A.6} and a Tree Retention Worksheet (Exhibit A. 7) were submitted with the short plat application materials. There are a total of 7 significant trees located on the project site. A total of 2 trees are proposed to be retained. To comply with the Tree Retention requirements, 2 trees are required to be retained or replaced. The proposal to retain 2 trees would comply with this requirement. Staff recommends as a condition of approval that a final Tree Retention plan in compliance with the City's adopted Tree Retention and Land Clearing Regulations be submitted at the time of Construction Permit application for review and approval by the Current Planning Project Manager. Note 3 Parking: Parking regulations require that a minimum of two parking spaces be provided for each detached dwelling. Driveway cuts are required to be a minimum of 5 feet from property lines and new driveways may be a maximum of 16 feet in width at the property line. Staff Comment: As proposed, each lot would have adequate area ta provide two off- street parking spaces. Compliance with the parking requirements would be verified at the time of building permit review. Compliance with driveway standards would be verified at the time of building permit review. Critical Areas: A high landslide hazard area and sensitive slopes (with a grade between 25 and 40 percent} are mapped on the project site. High landslide hazard areas and sensitive slopes are regulated under the City's Critical Areas Regulations (RMC 4-3-050}. Staff Comment: A Geotechnical Engineering Report prepared by GeoResources, LLC, dated December 22, 2014 (Exhibit A.BJ was submitted with the project application. According to the report the slopes on the project site range from 13 to 15 percent and are underlain with Indianola Loamy Sand. As the onsite slopes have grades less than 25 percent, the report (Exhibit A.BJ concludes that they would not meet the definition of sensitive slopes per the City's Critical Areas Regulations (RMC 4-3-050). In addition, the report also concludes that the presence of sandy soils onsite with grades between 13 to 15 percent do not meet the criteria for a high landslide hazard area and would instead meet the criteria for a low landslide hazard area. The report included recommendations for site preparation and grading, structural fi/1, foundation support, and floor slab support. Stoff recommends as a condition of approval that project construction be required to comply with the recommendations provided in the Geotechnical Engineering Report prepared by GeoResources, LLC, dated December 22, 2014. 3. DESIGN STANDARDS: Residential Design and Open Space Standards (RMC 4-2-115) are applicable in the R-8 zone. The Standards implement policies established in the Land Use and Community Design Elements of the Comprehensive Plan. Compliance with Site Design Standards must be demonstrated prior to approval of the subdivision. Compliance with Residential Design SHPL Report 14-00.1654 v2 City of Renton Deportment of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision LUAl4-00l654, SHPL-A Report of March 6, 2015 Page 8 of 21 Standards would be verified prior to issuance of building permits. The proposal is consistent with the following design standards, unless noted otherwise: Lot Configuration: One of the following is required: 1. Lot width variation of 10 feet (10' J minimum of one per four (4) abutting street-fronting lots, or 2. Minimum of four (4) lot sizes (minimum of four hundred (400) gross square feet size difference), or 3. A front yard setback variation of at least five feet (5') minimum for at least every four (4) abutting street fronting lots. Staff Comment: As proposed the short plat would comply with requirement number 1. Proposed Lot 1 would have a lot width of 71.50 feet and Lot 2 would have a lot width of 91.12feet. The difference in width between the street fronting lots (Lots 1 and 2) would exceed 10 feet. Note 3 Garages: One of the following is required; the garage is: 1. Recessed from the front of the house and/or front porch at least eight feet (8'), or 2. Located so that the roof extends at least five feet (5') (not including eaves) beyond the front of the garage for at least the width of the garage plus the porch/stoop area, or 3. Alley accessed, or 4. Located so that the entry does not face a public and/or private street or an access easement, or 5. Sized so that it represents no greater than fifty percent (50%) of the width of the front facade at ground level, or 6. Detached. The portion of the garage wider than twenty six-feet (26') across the front shall be set back at least two feet (2'). Staff Comment: Compliance for this standard would be verified at the time of building permit review. Note 3 Primary Entry: One of the following is required: 1. Stoop: minimum size four feet by six feet (4' x 6') and minimum height twelve inches (12") above grade, or 2. Porch: minimum size five feet (5') deep and minimum height twelve inches (12") above grade. Exception: in cases where accessibility (ADA) is a priority, an accessible route may be taken from a front driveway. Staff Comment: Lot 2 shall be required to provide vehicular access to the home from the access easement. However, it should be noted that the primary entry of the home should face NE 241h Street. To ensure the home maintains this orientation, staff recommends a condition of approval, that the primary entry features be located on the far;ade facing NE 'iHPf RPnnrT 1d-nnu:;r:;,1 lf? City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Report of March 6, 2015 Page 9 of 21 24th Street. Compliance for this standard would be verified at the time of building permit review. Note3 Fa~ade Modulation: One of the following is required: 1. An offset of at least one story that is at least ten feet (10') wide and two feet (2') in depth on facades visible from the street, or 2. At least two feet (2') offset of second story from first story on one street facing facade. Staff Comment: Compliance for this standard would be verified at the time of building permit review. Note 3 Windows and Doors: Windows and doors shall constitute twenty-five percent (25%) of all facades facing street frontage or public spaces. Staff Comment: Lot 2 shall be required to provide vehicular access to the home from the access easement. However, it should be noted that the windows and doors of the home should face NE 24th Street. To ensure the hame maintains this arientatian, staff recommends a condition af approval, that the windows and doors features be located on the fm;ade facing NE 24th Street. Compliance for this standard would be verified at the time of building permit review. N/A Scale, Bulk, and Character: N/ A Note 3 Roofs: One of the following is required for all development: 1. Hip or gabled with at least a six to twelve (6:12) pitch for the prominent form of the roof (dormers, etc., may have lesser pitch), or 2. Shed roof. Additionally, for subdivisions greater than nine (9) lots: A variety of roof forms appropriate to the style of the home shall be used. Staff Comment: Compliance for this standard would be verified at the time of building permit review. Note3 Eaves: Both of the following are required: 1. Eaves projecting from the roof of the entire building at least twelve inches (12") with horizontal fascia or fascia gutter at least five inches (5") deep on the face of all eaves, and 2. Rakes on gable ends must extend a minimum of two inches (2") from the surface of exterior siding materials. Staff Comment: Compliance for this standard would be verified at the time of building permit review. Note 3 Architectural Detailing: If one siding material is used on any side of the dwelling that is two stories or greater in height, a horizontal band that measures at least eight inches (8") is required between the first and second story. Additionally, one of the following is required: 1. Three and one half inch (3 1/2") minimum trim surrounds all windows and SHPL Report 14-001654 v2 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Report of March 6, 2015 Page 10 of 21 details all doors, or 2. A combination of shutters and three and one half inches (31/2") minimum trim details all windows, and three and one half inches (3 1/2") minimum trim details all doors. Staff Comment: Compliance for this standard would be verified at the time of building permit review. Note 3 Materials and Color: For subdivisions and short plats, abutting homes shall be of differing color. Color palettes for all new dwellings, coded to the home elevations, shall be submitted for approval. Additionally, one of the following is required: 1. A minimum of two (2) colors is used on the home (body with different color trim is acceptable), or 2. A minimum of two (2) differing siding materials (horizontal siding and shingles, siding and masonry or masonry-like material, etc.) is used on the home. One alternative siding material must comprise a minimum of thirty percent (30%) of the street facing facade. If masonry siding is used, it shall wrap the corners no less than twenty four inches (24"). Staff Comment: Compliance for this standard would be verified at the time of building permit review. 4. COMPLIANCE WITH SUBDIVISION REGULATIONS: RMC 4-7 Provides review criteria for proposed subdivisions. The proposed project is consistent with the following subdivision regulations if all conditions of approval are complied with: Note 1 Access: Alley access is the preferred street pattern in the R-8 zone, unless the development proposed is a short plat. As the proposed project is a short plat, it is exempt from the alley access requirements. There are two existing curb cuts, one is located on the southeast corner of Lot 1 and the other is located on the southwest corner of Lot 2. As part of the proposed short plat, the locations of the curb cuts are proposed to be relocated. Staff recommends, as a condition of approval, that the unused curb cuts be removed and replaced with curb and gutter, landscaping, and sidewalk. Revised frontage improvement plans showing the removal of the unused curb cuts and the replacement with curb and gutter, landscaping, and sidewalk shall be submitted at the time of Utility Construction Permit review for review and approval by the City's Plan Reviewer. Installation of the improvements shall be completed prior to final short plat approval. Access to Lots 1 and 2 is proposed via residential driveways off of NE 24th Street. Access to proposed Lot 3 would be provided via a new 18-foot wide private access easement located along the eastern portion of proposed Lot 2 with 16 feet of pavement. Per RMC 4-4-0801. 7.a joint use driveways should be encouraged to reduce the number of curb cuts along public street frontages, therefore, Lot 2 should also be required to take access off of the proposed access easement. Staff recommends as a condition of approval that access to Lot 2 be provided via the proposed access easement on the eastern portion of Lot 2. A note requiring the access to Lot 2 to be provided from the access easement shall SHPL RPnnrt ·14-nn1fiC,4 117 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision LUA14·001654, SHPL·A Report of March 6, 2015 Page 11 of 21 ,/ ,/ ,/ be recorded on the face of the final short plat map. A shared private driveway may be permitted for access up to a maximum of four (4) lots. Up to three (3) of the lots may use the driveway as primary access for emergencies. The private access easement shall be a minimum width of 16 feet with a maximum of 12 feet paved driveway, unless 20 feet is required by the Fire Department for emergency access. The applicant submitted a variance request to the Fire Department requesting a reduction in the 20-foot emergency access pavement requirement down to 16 feet with a fire sprinkler system to be installed within the future residence on Lot 3. The Fire Department has reviewed the requested variance and has approved the reduction in pavement width from 20 feet to 16 feet subject to the condition that the future residence on Lot 3 be equipped with a fire sprinkler system. Staff recommends as a condition of approval that a note be recorded on the final short plat map stating that the future residence to be constructed on Lot 3 shall be equipped with a fire sprinkler system. The minimum separation of access from the adjacent property line is five feet. The proposed access as shown in the plans provides the required five feet separation. Streets: NE 24th Street fronting the proposed project site is classified as a residential access street and has an existing right-of-way width of 57 feet. Per the street standards (RMC 4-6-060), the minimum right-of-way width required on a residential access street is 53 feet with 26 feet of paving, 0.5-foot curb, 8-foot landscape planter, 5-foot sidewalk, and street lighting. The existing right-of-way width is adequate, no additional dedication is required. Frontage improvements including paving, curb and gutter, 6.5-foot landscape strip, and sidewalk exist along the project frontage. The applicant submitted a modification to the street standards to allow the existing frontage improvements to remain. The requested Modification complies with the criteria outlined in RMC 4-9-250D per the approval letter dated February 12, 2015 (Exhibit A.11). Blocks: No new blocks would be created as a result of the proposed subdivision. The proposed short plat would be consistent with development patterns in the surrounding area. Lots: The size, shape, orientation, and arrangement of the proposed lots comply with the requirements of the Subdivision Regulations and the Development Standards of the R-8 zone, interim zoning standards (Ord. 5724) and allow for reasonable infill of developable land. All of the proposed lots meet the requirements for minimum lot size, depth, and width. All of the proposed lots are rectangular in shape. The front yard areas of Lots 1 and 2 would be oriented to the south toward NE 24 1h Street and the front yard of Lot 3 would be oriented to the east. Note 1 Topography and Vegetation: Sensitive slopes (with grades between 25 and 40 percent) and a high landslide hazard area are mapped on the project site, According to the submitted Geotechnical Engineering Report (Exhibit A.8), the existing ground surface generally slopes to the northwest with grades ranging from 13 to 15 percent. The submitted geotechnical report concludes that the onsite slopes and soil conditions would not meet the criteria for sensitive slopes and high landslide areas. A total of seven SHPL Report 14-001654 v2 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Page 12 of 21 significant trees have been identified on the project site and of these trees two are proposed to be retained. See previous discussion above under Tree Retention, and Critical Areas. 5, AVAILABILITY AND IMPACT ON PUBLIC SERVICES: Police: Police staff indicates that there would be minimal impact on police services as a result of the proposed subdivision and sufficient resources exist to furnish services to the proposed development. Fire: The fire flow requirement for a single family home is 1,000 gpm minimum for dwellings up to 3,600 square feet (including garage and basements). If the dwelling exceeds 3,600 square feet, a minimum of 1,500 gpm fire flow would be required. A minimum of one fire hydrant is required within 300-feet of the proposed buildings and two hydrants if the fire flow goes up to 1,500 gpm. It appears there is adequate fire flow in this area. There is an existing hydrant fronting the project site, which can deliver 1,000 gpm. Fire department apparatus access roadways are required to be minimum 20-feet wide fully paved. Fire access roadways shall be constructed to support a 30-ton vehicle with 322-psi point loading. Access is required within 150-feet of all points on the buildings. A 20-foot paved emergency access would be required to service proposed Lot 3. The applicant has requested a variance to the 20-foot pavement width requirement. The applicant is proposing a 16-foot paved driveway and the installation of a fire sprinkler system within the future residence to be constructed on new Lot 3. The Fire Department has approved the variance request. See previous discussion above under Access. A Fire Impact Fee for the future houses would be payable at the time of building permit issuance. The current Fire Impact Fee is $479.28; the fee in effect at the time of building permit application would be applied to this project. Schools: The Renton School District has indicated that it can accommodate the impact of additional students expected to come from the proposed project at Kennydale Elementary School, McKnight Middle School, and Hazen High School. Students attending Kennydale Elementary would walk to school heading west along the existing sidewalk on the north side of NE 24th Street to Jones Avenue NE where they would turn north and walk along the existing sidewalk along the east side of Jones to school. Students attending McKnight Middle School would walk to the east along the existing sidewalk on the north side of NE 24th Street to Edmonds Avenue NE where they would turn south and walk along the existing sidewalk to McKnight Middle School. Students attending Hazen High School would be bussed to school from the existing stop located approximately 0.09 miles to the east at the intersection of NE 24th Street and Aberdeen Avenue NE. To get to this bus stop, students would walk to the east along the existing sidewalk along NE 24th Street. The current Renton School District Impact Fee is $5,541.00. The Renton School Impact Fee would be payable at the time of building permit issuance; the fee in effect at the time of building permit application would be applied to this project. City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plat Report & Decision WA14-001654, SHPL-A Page 13 of 21 ./ Parks: A Park Impact Fee would be required for the future houses. The current Park Impact Fee is $1,441.29. The fee in effect at the time of building permit application is applicable to this project and is payable at the time of building permit issuance. Note 3 Stormwater: A Preliminary Technical Information Report (TIR) prepared by Encompass Engineering and Surveying (Exhibit A.9) and a geotechnical report prepared by GeoResources LLC (Exhibit A.8) were submitted with the project application. The geotech report (Exhibit A.8) states that the onsite soils are medium sand and are suitable for infiltration of stormwater. The submitted TIR (Exhibit A.9) states that the existing surface water runoff infiltrates into the existing soils. Runoff that does not infiltrate would sheet flow to the northwest onto the adjacent property and eventually into a biofiltration swale located 70 feet to the northwest of the project site. Surface flows continue through the swale and enters a piped storm system, which eventually discharges to Kennydale Creek and continues on to the 1-405 storm system. No drainage problems were identified. Infiltration trenches are proposed onsite to control surface water runoff generated by the proposed development. Infiltration trenches must be setback at least 15 feet from buildings with crawl space or basement. Runoff from roadways, driveways, and parking areas shall pass through a yard drain or catch basin fitted with a down-turned elbow, prior to entering the infiltration trench (see Figure C.2.2.B, p. C46). The elbow is intended to trap spilled material in the catch basin sump so that the spilled material can be cleaned up more easily by the homeowner. The preliminary grading plans (Exhibit A.4) show fill on a portion of the infiltration facilities. Having tractors or dozers go over these areas decreases their infiltration rate. Staff recommends, as a condition of approval, that no fill be allowed within the natural infiltration areas and compaction of the proposed infiltration areas shall not be permitted. An additional infiltration rate test will be required using the falling head permeability test for each infiltration area on each lot. There currently is not a rate provided in the submitted geotechnical report (Exhibit A.8). An additional pit test is required for Lot 3's infiltration area. These infiltration areas are very important because they are proposing full infiltration. Infiltration is not allowed for slopes greater than 1S%. Lot 3's test pit exploration should be conducted at the lowest elevation which is near the property line. The depth of exploration should be a minimum of 6 feet. Presence of high ground water in the testing, by a geotechnical engineer, may require additional mitigation elements, including storage and pumping during the construction utility review process. The special requirement #6 regarding Aquifer Protection Area should be included in the drainage report submitted with the utility construction permit. The site falls in the Aquifer Protection Area zone 2. Drainage plans and a final drainage report based on the City adopted 2009 Surface Water Design Manual Amendment and the 2009 King County Surface Water Drainage is required to be submitted with the Construction permit. All stormwater requirements as per the 2009 Surface Water Design Manual Amendment and the 2009 l<ing County Surface Water Drainage Manual is required to be provided by the project. Surface water system development fee is $1,350.00 per new lot. Fees are payable prior to issuance of the construction permit. SHPL Report 14-001654 v2 City of Renton Deportment of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Report of March 6, 2015 Page 14 of 21 / Water Service: The proposed development is within the City's water service area and in the Highlands 435-hydraulic zone. There is an existing 12-inch water main (see City water project plan no. W-1134) in NE 24th St. The 12-inch line can deliver 3,600 gallons per minute (gpm). The static water pressure is about 58 psi at elevation of 300 feet. There is an existing fire hydrant in front the property which can deliver 1,000 gallons per minute. The proposal will be required to install a 1-inch minimum domestic water service line and meter to each lot and may be required to install an additional fire hydrant within 300 feet of each lot, if required by Renton Fire Prevention Department for single family dwelling exceeding 3,600 sq. ft. of gross area. A redevelopment credit is applicable to an abandoned .3/4-inch meter that used to serve a house at 1908 NE 24th St that has been demolished in 2011. The development is subject to the water system development charge of$ 3,090.00 for the proposed lots. These fees are collected at the time a construction permit is issued and the rate prevalent at time of construction permit will be applicable. / Sanitary Sewer Service: The site is located in the city of Renton sewer service area. There is an 8-inch sewer main in NE 24TH Street. There are two existing sewer stubs for two existing lots. A 6-inch sewer extension from the existing 8-inch main at NE 24TH Street is required to provide access to proposed Lot .3. The development is subject to a wastewater system development charge (SOC) fee. The SOC fee for sewer is based on the size of the new domestic water to serve the new home on each lot. The sewer fee for a %-inch or 1-inch meter install is $2,135.00. The applicant is required to pay SOC fee for existing and proposed lots. The West Kennydale Interceptor Special Assessment District fee (SAD) will be applicable on this project. The SAD fee would be $1,050.00 per lot. / Transportation: See previous discussion above under Access and Streets. A Transportation Impact Fee for the new houses would be payable at the time of building permit issuance; the fee in effect at the time of building permit application would be applied to this project. The Transportation Impact Fee is $2,214.44. H. FINDINGS: Having reviewed the written record in the matter, the City now enters the following: 1. Request: The applicant is requesting approval of a 3-lot short plat on a 25,400 square foot site. The project would have a net density of 5.6 dwelling units per acre. 2. Application: The subject property is located at 1904 and 1908 NE 24th Street. 3. Comprehensive Plan: The subject property is designated as Residential Single Family (RSF) in the Comprehensive Plan. The proposed project would satisfy the objectives and policies of the Land Use and Community Design of the Comprehensive Plan, if all conditions are complied with. 4. Zoning: The proposed project site is zoned Residential -8 dwelling units per net acre (R-8) and is subject to the interim zoning standards as adopted under Ordinance 5724. The project City of Renton Deportment of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Page 15 of 21 as proposed would satisfy the R-8 standards and regulations as well as the interim zoning standards, if all conditions are complied with. 5. Subdivision Regulations: The project as proposed would satisfy the requirements of RMC 4-7, Subdivision Regulations if all conditions are complied with. 6. Existing Land Uses: The subject property is currently vacant. 7. Setbacks: Building setbacks for the future houses on the new lots would be verified at the time of building permit review. 8. System Development Charges: The surface water service development fee is $1,350.00 per single-family lot. System development fee (SOC) for sewer is based on the size of the new domestic water to serve the houses on each lot. Sewer SDC fee for %-inch or 1-inch meter install is $2,135.00. Water SDC fee for %-inch or 1-inch meter install is $3,090.00. 9. Public Services: The proposed short plat has been reviewed by various City Departments. There are adequate public services and facilities to accommodate the proposed short plat. Transportation, Fire, and Park Impact fees are applicable for the future houses on the new lots. Impact fees are assessed at the time of building permit application and are payable at the time of building permit issuance. 10. Public Utilities: Water, sewer, and storm drainage would be provided by the City of Renton. 11. Schools: The Renton School District has indicated that adequate school facilities are available at Kennydale Elementary, McKnight Middle, and Hazen High Schools. A Renton School District Impact Fee would be assessed at the time of building permit application and would be payable at the time of building permit issuance. 12. Safe Routes to Schools: Students would walk to Kennydale Elementary and McKnight Middle Schools. Renton School District bus service is available to Hazen High School. There are safe walking routes to Kennydale Elementary and McKnight Middle schools as well as to the existing bus stop located at NE 24th Street and Aberdeen Avenue NE. 13. Topography/Critical Areas: Sensitive Slopes (slopes with grades between 25 and 40 percent), a high landslide hazard area, and Aquifer Protection Area 2 are mapped on the project site. According to the submitted geotech report (Exhibit A.8), the existing ground surface generally slopes to the northwest with grades ranging between 13 and 15 percent. According to the geotech report the onsite slopes do not meet the City's criteria for Sensitive Slopes or High Landslide Hazard Areas, and instead should be classified as Low Landslide Hazard Areas as they meet the Low Landslide Hazard Area criteria. I. CONCLUSIONS: 1. The subject site is located in the Residential Single Family Comprehensive Plan designation and complies with the goals and policies established with this designation. 2. The subject site is located in the Residential -8 dwelling units per acre (R-8) zoning designation and is subject to interim zoning adopted under Ordinance 5724 and complies with the zoning and development standards established with these designations provided the applicant complies with City Code and conditions of approval. SHPL Report 14-001654 v2 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Page 16 of 21 3. The proposed 3-lot short plat complies with the subdivision regulations as established by City Code and state law provided all advisory notes and conditions are complied with. 4. The proposed 3-lot short plat complies with the street standards, as established by City Code, provided the project complies with all advisory notes and conditions of approval contained herein. 5. Slopes with grades between 15 and 25 percent and a medium landslide hazard area are mapped on the project site. Sensitive Slopes (slopes with grades between 25 and 40 percent), a high landslide hazard area, and Aquifer Protection Area 2 are mapped on the project site. According to the submitted geotech report (Exhibit A.8), the existing ground surface generally slopes to the northwest with grades ranging between 13 and 15 percent. According to the geotech report the onsite slopes do not meet the City's criteria for Sensitive Slopes or High Landslide Hazard Areas, and instead should be classified as Low Landslide Hazard Areas as they meet the Low Landslide Hazard Area criteria. The proposed 3-lot short plat complies with the critical areas regulations as established by City Code provided the applicant complies with the conditions of approval. 6. There are safe walking routes to the schools and school bus stop. 7. There are adequate public services and facilities to accommodate the proposed short plat. J. DECISION: The NE 24'h Street Short Plat and street modification (Exhibit A.11), File No. LUA14-001624, SHPL- A, is approved and is subject to the following conditions: 1. A detailed landscape plan shall be submitted at the time of Construction Permit application for review and approval by the Current Planning Project Manager. The detailed landscape plan shall include, but is not limited to, two trees within the front yard area of Lot 3 and show the relocation or replacement of one street tree along NE 24th Street. The 10-foot landscaped strip shall be installed prior to final short plat recording and the street/front yard trees shall be installed prior to final building occupancy. 2. A final Tree Retention plan in compliance with the City's adopted Tree Retention and Land Clearing Regulations shall be submitted at the time of Construction Permit application for review and approval by the Current Planning Project Manager. 3. Project construction shall be required to comply with the recommendations provided in the Geotechnical Engineering Report prepared by GeoResources, LLC, dated December 22, 2014. 4. Revised frontage improvement plans showing the removal of the unused curb cuts and the replacement with curb and gutter, landscaping, and sidewalk shall be submitted at the time of Utility Construction Permit review for review and approval by the City's Plan Reviewer. Installation of the improvements shall be completed prior to final short plat approval. 5. Access to Lot 2 shall be provided via the proposed access easement on the eastern portion of Lot 2. A note requiring the access to Lot 2 to be provided from the access easement shall be recorded on the face of the final short plat map. 6. A fire sprinkler system shall be required within the future residence to be constructed on new Lot 3. A note to this effect shall be recorded on the final short plat map. <::/.-IP! Pann,·+ 1/l nnlt::L.il ,,? City of Renton Deportment of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plat Report & Decision LUA14-001654, SHPL·A Page 17 of 21 7. No fill shall be allowed within the natural infiltration areas and compaction of the proposed infiltration areas shall not be permitted. 8. A minimum of two existing mature street trees shall be retained. The updated tree retention plan identifying retention of two street trees shall be submitted at the time of Construction Permit application for review and approval by the Current Planning Project Manager. 9. Primary entry features and windows and doors shall be located on the fa~ade facing NE 241 h St. Compliance with these standards shall be show on the building permit application for Lot 2. DATE OF DECISION ON LAND USE ACTION: SIGNATURE: Jennifer Henning, Plannin{J,Director TRANSMITTED this 5th day af March, 2015 to the Owner/Applicant/Contact: Owner: John Cowan 1830 NE 24" Street Renton, WA 98056 Applicant: Bill Hughes 14404 lssaquah-Habort Raad Issaquah, WA 98027 TRANSMITTED this 5th day of March, 2015 to the Parties of Record: Polly And Carl Brooks 2414 Kennewick Place NE Renton, WA 98056 Matthew and Patti Mark 2420 Kennewick Place NE Renton, WA 98056 Steve and Veronica Dinkins 2413 Kennewick Place NE Renton, WA 98056 Robert DuWors 2508 Kennewick Place NE Renton, WA 98056 TRANSMITTED this 5th day of March, 2015 to the following: Jennifer Henning, Planning Director Steve Lee, Development Engineering Manager Jan Conklin, Development Services Vanessa Dolbee, Current Planning Manager Fire Marshal SHPL Report 14-00.1654 v2 J/?,/2015 Date Contact: Tom Redding Encompass Engineering & Surveying 165 NE Juniper Street, Suite 201 Issaquah, WA 98027 lames Dixon 2517 Kennewick Avenue NE Renton, WA 98056 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Administrative Short Plat Report & Decision WA14-001654, SHPL-A Page 18 of 21 K. LAND USE ACTION APPEALS, REQUEST FOR RECONSIDERATION, & EXPIRATION: The administrative land use decision will become final if the decision is not appealed within 14 days of the decision date. APPEAL: This administrative land use decision will become final if not appealed in writing to the Hearing Examiner on or before 5:00 PM on March 20, 2015. An appeal of the decision must be filed within the 14-day appeal period (RCW 43.21.C.075(3); WAC 197-11-680), together with the required fee to the Hearing Examiner, City of Renton, 1055 South Grady Way, Renton, WA 98057. RMC 4-8- 110.B governs appeals to the Hearing Examiner and additional information regarding the appeal process may be obtained from the City Clerk's Office, (425) 430-6510. EXPIRATION: The administrative short plat decision will expire two (2) years from the date of decision. A single one (1) year extension may be requested pursuant to RMC 4-7-070.M. RECONSIDERATION: Within 14 days of the decision date, any party may request that the decision be reopened by the approval body. The approval body may modify his decision if material evidence, not readily discoverable prior to the original decision, is found or if he finds there was misrepresentation of fact. After review of the reconsideration request, if the approval body finds sufficient evidence to amend the original decision, there will be no further extension of the appeal period. Any person wishing to take further action must file a formal appeal within the 14-day appeal time frame. THE APPEARANCE OF FAIRNESS DOCTRINE: provides that no ex pa rte (private one-on-one) communications may occur concerning the land use decision. The Doctrine applies not only to the initial decision, but to Appeals to the Hearing Examiner as well. All communications after the decision/approval date must be made in writing through the Hearing Examiner. All communications are public record and this permits all interested parties to know the contents of the communication and would allow them to openly rebut the evidence in writing. Any violation of this doctrine could result in the invalidation of the appeal by the Court. ADVISORY NOTES TO APPLICANT The following notes are supplemental information provided in conjunction with the administrative land use action. Because these notes are provided as information only, they are not subject to the appeal process for the land use actions. Planning: 1. Construction activities shall be restricted to the hours of 7:00 am to 8:00 pm, Monday through Friday. Work on Saturdays shall be between the hours of 9:00 am and 8:00 pm. No work shall be permitted on Sundays. 2. RMC 4-4-030C.2 limits haul hours between the hours of 8:30 am and 3:30 pm, Monday through Friday unless otherwise approved by the Department of Community and Economic Development. Technical Services: 1. Note the City of Renton land use action number and land record number, LUA14-001654 and LND 20 0616, respectively, on the final short plat submittal. The type size used for the land record number should be smaller than that used for the land use action number. 2. Provide short plat and lot closure calculations. 3. Note discrepancies between bearings and distances of record and those measured or calculated, if SHPL Report 14-001654 v2 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Administrative Short Plot Report & Decision LUA14-001654, SHPL-A Report of March 6, 2015 Page 19 of 21 any. 4. Note addresses from the attached on the final short plat drawing. 5. Do note encroachments, if any. 6. Do include a "LEGEND" block for the short plat drawing, detailing any symbols used thereon. Include symbols for the 8' wood fence, 5' cyclone fence, 4' wood fence, rockery, etc. 7. Remove the various patterns (dots) noted in the street (NE 24TH STREET), the existing driveway, the existing gated tract road and the proposed 16-foot paved driveway. 8. Remove the building setback lines from all three lots. Setbacks are determined when permits are issued. 9. Remove all references to trees, currently shown on all three lots, from the short plat submittal. 10. Note all easements, covenants and agreements of record on the drawing. 11. Note any relevant researched resources on the short plat submittal. 12. Note that the correct page reference for the plat of Sunset Hills (noted for lots surrounding the subject short plat site on the drawing sheet) is PGS 5155, not "PG 52". 13. Remove the zoning, proposed net density, max allowable density, critical areas and critical areas buffer information and the proposed public street dedication information from the final short plat submittal. Also remove the "PROPERTY OWNER" AND "ENGINEER/SURVEYOR" blocks. 14. Add a north arrow to the "VICINITY MAP". 15. The City of Renton Administrator, Public Works Department, is the only city official who signs the final Short plat submittal. Provide an appropriate approval block and signature line for said administrator. Pertinent King County approval blocks also need to be noted on the submittal. 16. All vested owner(s) of the subject final short plat site need to sign the final short plat drawing. Include notary blocks as needed. 17. Include a declaration block on the drawing, titled "OWNERS' DECLARATION" not "CERTIFICATION" or other. 18. Because the subject property falls within Zone 2 of the City of Renton Aquifer Protection Area, the Aquifer Protection Notice needs to be noted on the drawing. AQUIFER PROTECTION NOTICE The lots created herein fall within Zone 2 of Renton's aquifer protection area and are subject to the requirements of the City of Renton Ordinance #4367. This city's sole source of drinking water is supplied \ from a shallow aquifer under the city surface. There is no natural barrier between the water table and ground surface. Extreme care should be exercised when handling of any liquid substance other than water to protect from contact with the ground surface. It is the responsibility of the homeowners to protect the city's drinking water. 19. Note that if there are easements, restrictive covenants or agreements to others (City of Renton, etc.) as part of this subdivision, they can be recorded concurrently with the final short plat. The final short plat drawing and the associated document(s) are to be given to the Project Manager as a package. The recording number(s) for the associated document(s) are to be referenced on the final short plat drawing. Provide spaces for the recording numbers thereof. 20. The new easements for ingress, egress, utilities (private?) and the 5' private sewer easement, shown for the benefit of future owners of proposed Lot 3, each need a note defining the rights associated with the easement at issue. Since these new "proposed" easements shown aren't "granted and conveyed" until the benefited and/or burdened lots are conveyed to others, add the following language on the face of the short plat drawing: SHPL Report 14-001654 v2 City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 DECLARATION OF COVENANT: Administrative Short Plat Report & Decision LUA14-001654, SHPL-A Page 20 of 21 The owners of the land embraced within this short plat, in return for the benefit to accrue from this subdivision, by signing hereon covenant and agree to convey the beneficial interest in the new private easements shown on this short plat to any and all future purchasers of the lots, or of any subdivisions thereof. This covenant shall run with the land as shown on this short plat. The preceding statement obligates the seller of the lots created to "expressly grant and convey" the lots "together with and/or subject to" any new private easements delineated on the short plat in the conveying document. 21. A private ingress, egress and utility easement requires a "New Private Easement for Ingress, Egress and Utilities Maintenance Agreement" statement. 22. The width of the proposed driveway easement changes as it crosses the 10 Utility Easement adjacent to NE 24th Street northern right of way margin but that width is not shown. 23. The easement lines shown along the property line between the two lots don't exist as the lots are excepted from the CC&RS, Water: 1. There is an existing 12-inch water main (see City water project plan no. W-1134) in NE 24th St. The 12-inch line can deliver 3,600 gallons per minute (gpm). 2. The static water pressure is -about 58 psi at elevation of 300 feet. 3. There is an existing fire hydrant in front the property which can deliver 1,000 gallons per minute. 4. Separate domestic water meters, minimum 1-inch, are required to serve each single family lot. 5. Installation of an additional fire hydrant within 300 feet of each lot if required by Renton Fire Prevention Department for single family dwelling exceeding 3,600 sq-ft of gross area. 6. Subject to payment of applicable water system development charges and water meter installation fees for the new lots. A redevelopment credit is applicable to an abandoned 3/4-inch meter that used to serve a house at 1908 NE 24th Street that has been demolished in 2011. Sewer: 1. Sewer service is provided by the City of Renton. 2. There is an 8-inch sewer main in NE 24TH Street. 3. There are two existing sewer stubs for two existing lots. 4. Applicant must tap a 6" sewer pipe to 8" main at NE 24TH Street and extend it through the new proposed lot. 5. The building footprint cannot intrude within the sewer easement. Surface Water: 1. Infiltration trenches must be setback at least 15 feet from buildings with crawl space or basement. 2 .. Runoff from roadways, driveways, and parking areas shall pass through a yard drain or catch basin fitted with a down-turned elbow prior to entering the infiltration trench (see Figure C.2.2.B, p. (46). The elbow is intended to trap spilled material in the catch basin sump so that the spilled material can be cleaned up more easily by the homeowner. 3. Special requirement# 6 Aquifer protection. City of Renton Department of Community & Economic Development NE 24TH STREET SHORT PLAT Report of March 6, 2015 Transportation /Streets: Administrative Short Plot Report & Decision lUA14-001654, SHPL-A Page 21 of 21 1. All meter boxes installed in concrete or paved driveways shall be cast iron equal to Olympic Foundary. 2. All electrical, phone, and cable services and lines serving the proposed development must be underground. The construction of these franchise utilities must be inspected and approved by a City of Renton inspector prior to recording the plat. 4. Traffic Impact Fees -Transportation Impact Fee is applicable on single family houses based on the applicable rate at the time of building permit, and payment is due at the time of issuance of the building permit. Fire: 1. The Fire Impact Fees are applicable at the rate of $495.10 per single family unit. This fee is paid at time of building permit. 2. The fire flow requirement for a single family home is 1,000 gpm minimum for dwellings up to 3,600 square feet (including garage and basements). If the dwelling exceeds 3,600 square feet, a minimum of 1,500 gpm fire flow would be required. A minimum of one fire hydrant is required within 300-feet of the proposed buildings and two hydrants if the fire flow goes up to 1,500 gpm. 3. Fire department apparatus access roadway is required to be minimum 20 feet wide fully paved. Applicant has requested a variance to reduce the 20 foot wide roadway to 16 feet on the condition that the home on Lot 3 be equipped with an approved automatic fire sprinkler system. The fire department has no objection to this varrance request. SHPL Repo1t 14-001654 v2 ~~·r ! . . :n '. ,r; •\.'i>I ~f,J!! '-(!JS1'!;414 7?',J~Q<oPS- :,,·,;;«- '"4L '·,~~, :-,~5 l . ."JAD5 AS "!(!-'.Y.:!lSJ'J;.,(100()7 _,f::Y' ~'112 :-;~e,1 ;.;S{", ,,. ,;-·,., //1]0!:Uil:l\ !l ~!UI ,".-~ ''··',!l .' H \.! .)~ 1,G :0011 > ',.-;'l •a ;.;;n/ )f,4i "' ,;,za '(.7) l:'l.·H u,·:,n1 ::~!!21 :·,1.:, 1121 o.;l -;'-OT 1 -; LOT 2 ;;,THI '.Jl'.~J :-; I.~. !. ;-J, ,lo' ,,r -~. HI u..;' " . ~ i; I;; ,..----·-·-~ ,{ti.~P '-!J l:JI ")(l~ ' ,c.<:-· ,r_,:.,,;;l}:c;,,.'-1. ·< ;1 ~~-;!I ,. ... ,; ''" ?~JU . ,x,6() ;, t< ~~-o·,.,~ -~ CJJ.H 02.U{J.j~IPL i"a(!iJ015 1 Al 5,;~'.li ~ }lH.3 "r.,a.,a oi"' ...-~---f~::i----"-"'-'r-,,,.,,---t"""'"-"'" -' j ~ f ~f{l'l$P !.UAG b~;,,...,,..,,.,. ... .,.t ,01.1~. ., -'.! '., l'.'1H (,t:JO ·o: .11 ,.,.,l ·~ ~ -""'· -~,,. ."~. ~<:l r;,110 ti LDT) ~~-·. ,;I~·-~"': ,, 1,.: ' j__. "-"'-.'"' --::-"':"~· ---.-.---r~r":l~~t---:--:---,---b" ··::~·:::;:d· r~: ,·-.· .. ·•'I --.-, .. ,, rm SP Ll/,0,.-11 (lll6-.5tiPL ).!)12,:;,r..1;1)i;~t,,j! JJ .. , :n '1. ' ·.i; '0 z a , ;~ C) u '' ,, H· 1 · .I Hli w. ~· t " a ' C " < u ,, 0 ]N " 0 • 0 ".I 0 J ~ ,I "' ;,J ~ Q w " ~ "' '° N ! ,ri 0 d ~ ~ • C; :'5 cJ "' ~ , .. 3 .. ~ i. __ r ___ ~_J __ _J __________ _ ·TN 3DtBJ\'d }3~31NOW ____ J ---- ·1- I l I I I I I· ' ! I i I I I ' J ,f _ L. __ . I J . ~-"J ' ,, I I J .o---L-- t " • • e C, £~ z ta: !~ '-:l • Exhibit A.3 ~i "" :~ .. ,r;~ t,1:' ,~ ~§ t';> ' • _,_ ------------------n ----· ----•~ ---• ---••----~-~-----~-- Exhibit A.4 ~ -~ ,~.:.-~·.:.,".='.:',:\.-"!"::;'@ :'.IW>< i ""'"' -J.~ u. s,,o~~i, l l~-----0 H'lf1d All111n/3DVNl'lf1JG .U9J.OO!iln 11Wll3d 1V1d lHQHS 101-f: Hltl 3N ·"· ''''''·"" ~,. ',>, ''"""' -· '""' '"~"""' '""'"'' •. , ,~, -·-·~.._., .. ~,. '"~·'' "·" ~ ...... '""'"~"""""· "'~' ·=~'"""' "'''' -·-"--"' r:J sseciUR:Y:5U3 1 I :;.·.- ii' I tt c'""--- ; ii Ii"': · ,,I t ~-~ ~~~~ : ~ i~~; dJ• e_ +----~;1; I ·, ,1''-j----- 1 ,i ' ' ' ---i~ ., '" ~~ @If ,. !l ,. ,u '.IJ li. ,_: (~ < ') ! : '' j f ,]!ldllJ ii '' I \ i_ I i i! ~ . '' ,-, - ··! i; '.i ' ), ,. ,-, . ,. . 1? ) i, ;r.: I· I \.S ~ • I ' -:,_ i,\J ···-'i ,\: ·h ·1:; ,,,'.''j(,/ ,,'. :;} ;f. ., '' ;,·; :-:r,.~ ;." ;' -,. i-::: ,, I 'f /: :i ,,· I ·' :: ... ·; :,. , . I . I;? i I ·-i~~ :111: i. ,, · 1L .... ,;:1' '); . ' " ' . ' : i '1 t ·.; .i ExhL~it A 5 N.W. 114 OF N.E. 114 OF SECTION 05, T. 23 N., R. 05 E., W.M CITY OF RENTON, STATE OF WASHINGTON v---/-'"._!__,VI ___ _;_ ___ , ___ -----·-,·· :------{fi-:=\ : : )Xr -------,:t,·~ _r=·,_ ----fr,---V : I 1 I , / I / i,, , (: I / / / , 1 I I : I // // j-1 / l I t · I 1 / I /LOT .3 ! , 1 _J ' 1 1 ~;+r. I // 9,610SQ f"l c·-. •' -.. : 1· .. :.i I I / .. ' ·J ••I I // -••• _, // ::! 1 I / / I f.-1-/ // J-I / / I I T""' I_ / 1 1 I "ii// /V --7 -----1 1 : I / -.:·-1 ,.,,, / I I I .,,,, --i ' ,, / I , / )< ·,/ •• ~ o© I® 0 SICNIFICA>IT TREES ro SE REMOVEJ. s~~ 'REL Rl lE>I 110>1 PLA>I BY £~CINl~i,5 = i I / I / I / : v//f=-1 m ~ I "· -'"5'GNIF"1~"-"IT TRCE" ·~fl T Ii I 1 I I, LOT -, 7.021 so n I X ·1__ -r-1 I ;, I ! ' I I I l_Ol 2 I 8,161 SQ fl I (/,004 SQ FT NfT) ' I il I I . ' <I :1 REP•, A'.:[ME"T IRE[ [6) "01AL f-+---6' WOOD FE,.CE ltn 1 l ·. : I • 1.· · .. -+ 1B" SHAI'<[() ()R1vfWAY EASFMENT (11-<G~tss, EGRlSS AND UIILlllE~ :II 11 / L. .· // tr-~I I ! I ---'1:>H-~----10· PROPOSED P1wEO DR1vrwAY , , , . , / ~ 1 -~ I .1. ___ H"I" Ml~ 0>1-S1lf I AN(lSCAP[ AL 0~() ~ _ _ · ' ,: ~I I STRffT rno~-AGES , ' I I I ~LANT MATERIAL PER PLA"T SCHED~LC ON THIS SHEET EXIS"NG SIDtWAL,.; JRl~[w,, y _\: [Qq:;9.:.. . .,; .. : 0. ~·~:::.. . . : : : ~~p :~_l-~-_:_g1s~~NiE~T~S:tE~ iRtE [s'.HtR,,Y) z \ _.. ·. .. HISTING 1Rf'.ES ~Ct REMAIN (TYP.) (D LAND.SC. APE PLAN SCAlE 1"--IO' O" ~ o ,a ~-------t -------~~"s-------~XISTl"'C LAY/'1 ·o RE,,.A•N , /\( t_, 'if° / . .' ('.\ 1 ,Vt,,''t,1 1 · ! \. l'V'1, V\("-),:' /"; , I ,, , '"'-,-,,\ NEW DRIVCWAY ,..__, r·---, (:-.'·~r r~, .,_/e,_'~\\1.~~L ~ '.l\ .. --... i!-,-1~,_,r:~ ,.--c..,-., PLANT SCHEDULE SOTN<IC'L..._.,S "°""°""""" TREES 1, ... ---...-WOIO,_..,,M"""""""" ·--.,....,,,_... .. --.. ......... c, .. ,, ,,,,.~, '" '"'""'~"'"'~"""''~··· '"' ~'..:: . ..:."~~;"""'""' SHRL.eS ... M~~·S, ... dU,o "" ............ ... ·-Mn..-. ... ..,.. ........ ,.. '"'""'"'-~--. """"""'" ...... GllO</NDCOVERS A«.l•d•-•w•o~ ':<;.:,;;- i ,,.,1~ ,,.. '""'°""""""''•''""''"' ,.,...,,,..,..,. .... , .. '"°'C"""'"-'"'"-'it'·'""""' """'"''"" ,,~ '"''"""-""'"'' '°"""...,"""' ,,~ '""'c"""'·''""'' -~-.. -,... , .. ,c., ..... .......... , .. ~ '"" ···~·'""-'-"'·'""""' "'''--""""" "''"'' .. "''"""""""' " -ti - !~ ..... ~--Jr'li/ 4-·/J • ._,.)( :. .. ;:,_ ... :, ·'~-T'.)/;. ?-c '!("-/;., '00'',,. ' ,, ,r,t -· !"". -"'°"·''-'..c'.' Call before you Dl9, 1-aoo-424--5555 IN COMPLIANC< WrTH CITY OF RE'ITO~ STANDARDS BY ~ ·----Date BY: o.ite._ av: c,,,i,, " Date~---- --- " -~ ~ 0' tl ~ Ji <I ~i §-,1 : .. _t > 0 "' V.-,::~ ~3;'.! ~~~ tit'.;~ :.i.:c.:::o.. c "' ~ N '" z ;z :s11 ""I g; 0 i6 ~ ,-) LA-1 City of Renton TREE RETENTION WORKSHEET 1. Total number of trees over 6" in diameter1 on project site: 1. ___ 7 ___ trees 2. Deductions: Certain trees are excluded from the retention calculation: . .Trees that are dead, diseased or dangerous2 -~o __ trees Trees in proposed public streets O trees Trees in proposed private access easements/tracts o trees Trees in critical areas 3 and buffers O trees Total number of excluded trees: 3. Subtract line 2 from fine 1: 2. 3. o trees ------- --~? __ trees 4. Next, to determine the number of trees that must be retained 4 , multiply line 3 by: 0.3 in zones RC, R-1, R-4, or R-8 0.1 in all other residential zones 0.05 in all commercial and industrial zones 4. __ 2.1 _____ trees 5. List the number of 6" or larger trees that you are proposing 5 to retain 4 : 5. ___ z_(,___ trees ,8 \ 6. Subtract line 5 from line 4 for trees to be replaced: 6. trees ---(!f line 6 is less tt1an zero, stop here. No replacement trees are required). 7. Multiply line 6 by 12" for number of required replacement inches: 7. _A_(;, __ inches 8. Proposed size of trees to meet additional planting requirement: 1 ' (Minimum 2'' caliper trees required) 8. 1,; inches --''------ per tree 9. Divide line 7 by line 8 tor number of replacement trees 6: (if remainder is .5 or greater, round up !o tlie next w~10Je number} 1 Measured at chest height. 9. __ G ____ trees 2 Dead, diseased or dangerous trees must be certlfled as such by a forester, rngislered landscape architect, or cert'rfied arboris!, and approved by the City. J Cri1ical Areas, such ::is wetlands, streams, floodplains and protected slopes, are defined in Section 4-3-050 of lhe Renton Municipal Code (AMC) 1 Count only those trees to be retained outside of crilical areas and buffers. 3 · The City may require modification of ttie tree retention plan to ensure retention of lhe maximum number of 1rees per AMC 4-4-130H7a 6 Inches of street trees, inches of trees added to critical 2reasibuffers. and inches of trees retainaa on si!e !hat are less than 6" but are greater than 2" can be used to meet the tree replacement requirement H: ICE TJ\Dm a \forms Temp I a(e,~\S elf-He! p Handouts \P/a 11 r; in g\ Tree Retention \.Vorks heet Uoc J::!/08 Exhibit A. 7 Plt 253-896-1011 Fx 253-896-2633 WH Hughes Company, Inc. GeoResources, LLC 5007 Pacific Hwy E., Ste. 16 Fife, Washington 98424 December 22, 2014 14404 Issaquah-Hobart Raad, Suite 104 Issaquah, Washington 98027 (425) 444-3367 Mr. Bill Hughes Geotechnical Engineering Report Proposed Short Plat NE 24th Street Renton, Washington PN: 813210-0120 &-0130 Job No. WHHughes.NE24thSt.RG INTRODUCTION & SCOPE This report presents the results of our subsurface explorations, literature review, and engineering analysis and provides geotechnical design recommendations for the proposed short plat to be constructed on NE 24th Street in Renton, Washington, as shown on Figure 1. The site is currently undeveloped. The short plat will consist of three residences, two that occupy the bottom two thirds of each parcel, and the third occupies the top one third of each parcel. The short plat will be accessed via three new driveways, two oi the proposed driveways will extend north from NE 241' Street to the residences on the southern parcels, while the third driveway will extend between the two southern parcels back to the north lot. We anticipate that the residences will be 2-story, wood-framed structures supported on conventional spread and continuous concrete foundations. The remainder of the site will be covered with grass lawn and landscaping. Current site conditions and topography is included as Figure 2. The purpose of our services was to evaluate the surface and subsurface conditions at the site as a basis for developing and providing geotechnical engineering and stormwater management recommendations for the proposed development. Specifically, our scope of services for the project included the following: 1. Visiting the site and conducting a geologic reconnaissance to assess the site's soil, groundwater and slope conditions; 2. Exploring the subsurface conditions by excavating four test pits across the site; 3. Addressing the City of Renton Critical Areas Ordinance for potential geological hazards; 4 Providing geotechnical design recommendations for foundation, floor slab, and pavement; and 5. Providing infiltration rates for the stormwater facility, as appropr(ate:- Entire Document Available I lnr,n !=lorn t<>d Exhibit A.8 1 • ' En.~.QIYl!?iI?s V PRELI1\IIINARY TECFlNICAL INFOR.!vIATION REPORT for NE 24'h 3-Lot Short Plat 24XX NE 24th St. Renton, WA 98059 December 29, 2014 Encompass Engineering Job No. l 4690 Prepared For Hill Hughes 14401 Issaquah-Hobart RD [ssaquah, WA 98027 Exhibit A.9 Entire Document Available Upon Reauest Western W"shingtnn Division Eastern Washington Oil"isioa 165 NE Juniper St., Sre201, Issaquah, WA •JRfJ27 Phone: (·1251 W.?-02511 F:.1x: 1·!25) 19)-j()SS 108 East 2"' Street, Cle Elum, \VA 93922 Ph"ne: (509l674-7~J3 F:n: (509) 674-7419 w,-vw. Encompa::isES. r:et ··""'· ~ 0 En.~,QH1Jr?,~,?S V December 24, 20 l 4 Steve Lee, Development Engineering Manager City of Renton 1055 S Grady Way, 6th Floor Renton, WA 98057 RE: NE 24th Street 3-Lot Short Plat Street Modification Request Dear Steve; We are working on a preliminary short plat dividing 2 existing residential lots into three lot. We have been asked to provide, per code, a minimum R/W width of 53', a 26' wide paved road with 0.5' vertical curbs, 8' wide landscape strip, a 5' v,ide sidewalk, and street lights. Existing R/W width of 60 '. On the 30' subject side (north side) of the R/W, there is existing 18' of asphalt paving, a vertical curb, a 6.5' planter strip, a 5' sidewalk and four street trees and two spaced street lights in the planter strip--the sidewalk is butted up against the R/W. On the opposite side there is existing 16' of asphalt paving (total 34'), a vertical curb, and a 5' sidewalk (most of the way). The existing roadway is nice and provides the required more roadway than is currently required and also provides the required pedestrian improvements. The 6.5' planter strip is functioning as well. The existing street meets the required standards except that the planter strip is 6.5' rather that the code- specified 8'. Because the paving width is 2' wider on the subject side of the R/W, there is no room in the R/W for an additional 1.5' of planter strip without removing the curb and reconstructing it 1.5' into the existing roadway. We request that the frontage be allowed to remain as is without providing the additional 1.5' of planter strip. lfyou have questions or need additional information, please call me at 425-392-0250 or email me at trcdding(m.encornpasses,net Sincerely, Encompass Engineering ~~~l)l)r1vc, Tom Redding Western W~shington Division 165 NE Juniper St., Ste 20 I, Issaquah, WA 98027 Phone: (425) ]92-0250 Fax: (425) 391-3055 Exhibit A.10 Entire Document Available Upon Reauest E"stern Washington Division I 08 East 2"d Street, Cle Elum, WA 98922 Phone: (509) 674-7433 Fax: (509) 674-74 l 9 SECTION 3 OFF-SITE ANALYSIS Site Address: King County Tax Parcels: Project Overview 24XX NE 24th St., Renton, WA 98059 813210-0120 and 813210-0130 This project involves the development of two vacant parcels totaling 0.58 acres into three single- family lots in the Kennydale area. These parcels are located within Northeast Section 05, Township 23 North, Range 5 East, W.M. The existing topography of these parcels generally slopes down to northwest at approximately 10% to 25%. The existing parcels are vacant and is covered with lawn and several mature trees. Per the USDA Web Soil Survey, the site is underlain with Indianola fine to medium sand. -Refer to Sec. 6 of this TIR for geotech report and infiltration test results prepared by Geo Resources. Downstream Drainage Level I downstream analysis for this project was conducted on Dec 18, 2014. The weather on the day of the site visit was cloudy and rainy with the temperature of approximately 50oF. Runoff from the existing project site apparently infiltrates into the underlying sandy soil. That that will not infiltrate would sheet flow to northwest and drains through adjacent property on the northwest and then enters into a biofiltration swale located at point A, about 70-feet downstream from the project site. From there, flow drains through the swale and at the end of the swale enters into a 15-inch pipe. Then, flow continues west through the pipe and enters into a storm drainage manhole located at point B for a total of approximately 160-feet downstream from the project site. From there, flow continues west through a 15-inch pipe and enters into a storm drainage manhole along the west side of Kennewick Ave NE located at point C for a total of approximately 200-feet downstream from the project site. From there, flow continues south through a 15-inch pipe and enters into another storm drainage manhole located the intersection of Kennewick Ave NE and NE 24th St at point D for a total of approximately 430-feet downstream from the project site. From there, flow continues west through an 18-inch pipe and enters into another storm drainage manhole located at point E for a total of approximately 650-feet downstream from the project site. From there, flow continues west through an 18-inch pipe and enters into another storm drainage manhole located at point F for a total of approximately 780- feet downstream from the project site. From there, flow continues west through a pipe and crosses the Jones Ave NE and enters into another storm drainage manhole located at point G for a total of approximately 900-feet downstream from the project site. From there, flow continues west through a pipe and apparently enters into another storm drainage manhole at point H for a total of approximately I, 130-feet downstream from the project site. From there, flow discharges to the north side of the street through an 18-inch culvert pipe at point H into a heavily wooded but rocked chmmel of Kennydale Cree k, about 3' wide, 6' deep flowing northwest at point J. About 150-feet beyond the NE 24th Street R/W the flows pass through a tall fence. B ecause of tall fences and locked gates, the s tream could not be followed any further. Apparently the stream enters a storm conveyance system at the I-405 sound v.rall another 150-feet further, about 1,430- feet downstream from the project site. Th ere were no apparent drainage problems along the downstream drainageway. See Downstream Map and Photo's I through 5 below. ..-.c;:: Photo 1 : View of the subject properties-Sheet flow northwest Photo 2: Infiltration swale at point A Photo 3 : SDMH at point B Photo 4 : 18-i nch culvert pipe at point I Photo 5 : Stream channel at point J I ,_ ' / l t I -l, t \i!i.1 1 1 . "' ( ' \_ .! \I l. ! ! i i I I '1 Ii t _, / ( j I __ I '. \ '·.. \ ' \ \ i_ I ... I~ I i .I ,' I\ \ (" t~,, ,' ' ·-.. ,l... i ·1 I ' I I I I i \ I '· . I I C . I J . ,I I ,,/ ,.-. / { I i DOWNSTREAM DRAINAGE MAP ) / ·' ! {.- /,/ /' .... ___ -- '.,\ -\.\_ \ \ I l, '1 j '> I It '· ... ...,__ --............ \ \ \ ' '·'- ·-----..... , i \ \ ' .----.-... '! --·-\_ :~-------_/I i '\ I u.1·· -.,_ ·-t, \,_ .. ·, __ _ r I \ / I 1,) __ __.... ~ . -----~ ~\' .. ~-==~~----.: :~-=~-~~=:_____ -~-.. :·-__ I --.~- ··--..,, \ ·--.\ \. \ -i, !l ·, .. i /' .\\_! ':! I ,, \ \ .. ,\,, ' II '\,,, .... ) \\ I I, \ I, \, ' \ ....; l ' \ \_ .--,-!,. I I ---... _ . f ]_ ~} ......... __________ .. \ -'( ':i I, l ' .. l i /~\\ \ .. -1' '1 \,_ ,.-( ---,-~ II!~\ I lij ', ·' "! ', '· \ I I ~ , 1, I ' \ I ••. .•' \ 'tj 1.\". l ·, \, ,/ ''1 -.. ·,',•,, l ~~ I j ) ! \ \ -.. _____ i1 I i / ,I fl;:\, \ \__ ··1 \ "-.\ \ '; I I,,,\,\,!,:~ ,r } ,' -,l '-__ I _/·•._ i l ·, ', \ ! -__,_._. .! i \ _., •. ---·, _i ' \ ... '· .·j. .,. .• ,i \ .. t _.-'"' • I -1-" ! t. \ \ ·---· -. ) 1'l. / .--"' C\C ~ f \ \ '·,. . --· !! J / \'-..J p,,.. I ·-'1 ', /" ,, II J S -,_\',ii ..,. ~I \ f I ~ , 1 -If·.\\\ ~~---', \ 'j i ~ i;' ~-l-1, ... ,-,:, ·r,..'· ._.-:i '\ \ R~nton · ' • I '· ., I ' . '\ , ___ . ..., , " , ... " \ -. \_ -··r -! .. ' \ -' ', ·,, '"--~ l ,l ;e,/.. ~ \ l..f v·· /1!:'t. \ \ ' • '· " i <el '~'lJI'·~~ _! _ .. --___ , ·-I?\ /--__ \ \!:;I' \ ) • ,,, 't ,.--\\;?J. /. , 1, , C a«c&: *I l ~ i '""°-;,------I ·--,_,;; , ·-l r --, -. r •---4 ': ___ ) ' , ! --..... ...., ....... ,.,. ·-1 l } ) I / ... ----'\ ; ,...-\ ... -.1 ( ./~ i/··---. JI 1 , l , ' . .cl 1! : ~ \ I J ~-/ . ' ~ ! \ ~ c·· I :! \ 11_ ..... ,_\ --! r'/: ' / ,,/ • '; ·1 •• ---_. I "" i ! '!' ·---'-.. __ , i'~ i ' i , --. , ·, , ,· I ·, i· f l t ·---;. I 'j 1 . i I 1/ f., ______ \. •. \, ii~ '1 J If ) I!! l . i "·-.__ ' 1' ,I ' ,1 .··· .,...-·-I ! • I --. • I . ' -· I I ! I i -• · •. , -.. ', ', ', ' ~ \ ,' I .----~----: .,. i i t .--i --. \ \ . ·~·-~-.. -· ~ \, ! \ ! . !'.:' I ' ) . ' . ,, -~ ' ' l ' ... i 1 ,! , i ·1 1 ,, \ ' } .;J ->;( MO t'T ! I / I_ f I i!11 'I 1' ,. ....... i 11 , 'l I / ·-1·1 '1] I I ! I ' \ ! ~-r,_ ' W ,! 1 , . •' ; l! JI _I: . I \. \ \ ~· ··1 \ :, It i i / .. ,/· +Ii-', '· I I_ I 1 /r' '1· W"I 1, ., • '·· / I I I -_,l I' ,· : -.. ~ ·, ----. ~ ,..._ ---,,, .., \ ,, ~. ,· .r r' I I 11 0 .. -· . ~ ·, ' .. "' I i ! , r. ----·-I, ' \ \_ ,' . I !1,i 'I '11 ) \ _-·· i;'_II 1 I i .. · ,1 J;[; I 20(J;l!l l(m,g C.oo_n.t·t \ i, 11 __ / __ ________ -~ D 20.f!ft -· The informa1ion included on this map has been complied by King County staff from a varleiy of sources and is subject lo change without notice l(jng County makes no represenlations or warranties, express or implied. as tc accuracy, completeness. timeliness. 0r ~ghts to the use at sucn ,ntormatlon This dooument 1s not intended for use as a survey product King County j shall not be liable for any general. special indirect, ,ncidenta1 or consequent1a1 damages 1ncJuding, but •101 lirrnted to. 1ost ·evenues or lost orofits resulting from the use or misuse of the 1 ,ntonnation contained on this map Any sale of this map or 1nforma~on on this ma;:; 1s orohlb1ted except by whtten perm1ss1on of King County I Date: 1211712014 Source King County iMAP Property <ntormalion (tlUp:l/www.metrokc.gov/G!SliMAP1 i ( ·1, .// r' !I r I( ,' i, ·! 1, J I, ( \ ! _, ! i \. ", ' C, { 1. ( I ' I. ' '1 ) , ...... ' /_ .. · / ( ii _r i /. .! ,' // .· _.-· • l ' ,' ' .-· 11: -~ ... -"-----· )~ N 1" = 100' \ \ "1 King County I I SECTION 4 FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN ' ' l Proposed Drainage Controls Infiltration trenches will be used on the lots to provide full infiltration. Per the geotech report, the site is underlain with fine to medium sand. Full infiltration trenches were sized to provide 100-yr infiltration. Per the attached KCRTS analysis, 24. I LF of trench per I 000 sq-ft of impervious surface will provide I 00-year flow control. I I l Encompass Engineering & Surveying Eastern Washington Division 407 Swiftwater Blvd .. Cle Elum. WA 98922 Phone (509) 674-7433 Fax (509) 674-74!9 Western \Vashington Division SHEET NO--------OF-,-,-~--- CALCULATED BY _ ____,f_,lc___2--____ DATE 1/t,j; ~ 165 NE Juniper St., Suite 201, lssaquah, WA 98027 Phone (425) 382-0250 Fax (425) 391-3055 CHECKED BY--------DATE _____ _ SCALE---------------- ------- tf\JFct=Wrl-nGlfJ ll1£r--c.,1-H;s w,c,-L R~ ()'S I} 1> e "' N£w t "'-\ f ll-n-v Io u ---~~ .. . . I ············· ..... -72!n..-.. ,l!--~G tAJF'1LrI?A-1)4N ~$_T,-t. l~Sv l-T~: ..... ... . .. 0)()17-":> r ~E . Z. '"-' FtLl>'2e1 i)p,u T7i 'j {":> 7 1 , , r-. i NC.ff I} 0-1~d/Z__ ::::= I · .. ,..e~ r/-G·-:;r,"'f ~ -f2~30. · 'rj;lil,;.c.,,.,,... = · tP+§O · \ 'o'11 IV f .. ,-t,5'('RJ Encompass Engineering & Surveying Eastern Washington Division 407 Swifrwater Blvd., Cle Elum, WA 98922 Phone (509) 674-7433 Fax (509) 674-7419 Western Washington Division 165 NE Juniper St., Suite 20 I, Issaquah, WA 98027 Phone (425) 382-0250 Fax (425) 391-3055 SHEETNQ ------~ QF_~---- CALCULATED BY __ -_._! '-=J2-=------DATE 1/'¢ s CHECKED BY _______ DATE----- SCALE 'L1:>eS1 t.aN* '.L ":/ fZ-. . . 6l) "4c .. •1'1. .. Tu l)E~OM11.JE-ft D~7l"'LN Lo/!(f}~{)SF 6r I ivirert.\/1c7vs. tfp_ l){2-rr1Cr'Lj A tJ'?SI'tc (I../ -Pc_9(L .. s (}t20 ::Sf-Fr P'F IMfffrL//tofd5 .. ~vfl r?'tL.~ u~ 1 i(, ~ · · ILL 1c.rs c.u11 s . N RDI- --r -,.,. 'v.> ~ Encompass Engineering & Surveying Eastern \Vashington Division 407 Swiftwater Blvd., Cle Elum, WA 98922 Phone (509) 674-7433 Fax (509) 674-7419 Western Washington Division 165 1'E Juniper St, Suite 20 I, Lssaquah, WA 98027 Phone (425) 382-0250 Fax (425) 391-3055 SHEET NO.-----------OF ________ _ CALCULATED BY---------DATE -------- CHECKED BY __________ DATE-------- SCALE ---------------------- .Jl;i1~1 .. ~L~kf . ]')~'z/ ,t ~. -._.. \ .··~ .. "'· ~ ..... -. ., __ ~_ /6 l )(,. I • c .... /9D -------------------- ---~----...... ..... - --z,. 3 t-/.=- 1"'-'F t c..lnt!. 'i2 s fl.... 7Yl.£Aelt KCRTS Peaks for 5,000 sq-ft Impervious Surface Flow Frequency Analysis Time Series File:14690d.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks Rank Return Prob (CFS) (CFS) Period 0.028 7 2/09/01 2:00 0.054 1 100.00 0.990 0.024 8 1/05/02 16:00 0.042 2 25.00 0. 960 0.034 3 12/08/02 18:00 0.034 3 10.00 0.900 0.028 6 8/26/04 2:00 0.034 4 5.00 0.800 0.034 4 10/28/04 16:00 0.030 5 3.00 0.667 0.030 5 1/18/06 16:00 0.028 6 2.00 0.500 0.042 2 10/26/06 0:00 0.028 7 1. 30 0.231 0.054 1 1/09/08 6:00 0.024 8 1.10 0.091 Computed Peaks 0.050 50.00 0.980 100-yr 100-year Infiltration Trench Design of 5,000 sq-ft Impervious Surface Retention/Detention Facility Type of Facility: Gravel Infiltration Trench Facility Length: Facility Width: 72.00 5.00 360. 2.00 0.00 216. 14.90 ft---+ 14.4LF/1000 sq-ft impervious ftv'" Facility Area: Effective Storage Depth: Stage O Elevation: Storage Volume: Vertical Permeability: Permeable Surfaces: Riser Head: Riser Diameter: Bottom sq. ft V ft V ft cu. ft V min/in V 2.00 ft V 4. 00 inches v' Top Notch Weir: None Outflow Rating Curve: None Stage (ft) 0.00 0.02 0.12 0.22 0.32 0.42 0.52 0.62 0.72 0.82 0.92 1. 02 1.12 1.?7 1. 32 1. 42 1. 52 1. 62 1. 72 1. 82 1. 92 2.00 2.10 2.20 2.30 2.40 2.50 2.60 2.70 2.80 2.90 Elevation ( ft) 0.00 0.02 0.12 0.22 0.32 0.42 0.52 0.62 0.72 0.82 0.92 1. 02 1.12 1. 22 1. 32 1. 42 1. 52 1. 62 1. 72 1. 82 1. 92 2.00 2.10 2.20 2.30 2.40 2.50 2.60 2.70 2.80 2.90 (cu. Storage ft) (ac-ft) 0. 0.000 2. 0.000 13. 24. 35. 45. 5 6. 67. 78. 89. 99. 110. 121. 132. 143. 153. 164. 175. 18 6. 197. 207. 216. 216. 216. 216. 216. 216. 216. 216. 216. 216. 0.000 0.001 0.001 0.001 0.001 0.002 0.002 0.002 0.002 0.003 0.003 0.003 0.003 0.004 0.004 0.004 0.004 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 Discharge (cfs) 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.103 0.188 0.230 0.266 0 .297 0.326 0.352 0.376 0.399 Percolation (cfs) 0.00 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 Hyd 1 2 3 4 5 6 7 8 3.00 3.10 3.20 3.30 3.40 3.50 3.60 3.70 3.80 3.90 4.00 3.00 3.10 3.20 3.30 3.40 3.50 3.60 3.70 3.80 3.90 4.00 Inflow Outflow Target 0.05 0.00 0.04 ******* 0.03 ******* 0.03 ******* 0.03 ******* 0.03 ******* 0.03 ******* 0.02 ******* Cale 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 216. 216. 216. 216. 216. 216. 216. 216. 216. 216. 216. Peak Stage 2.00 0.23 0.03 0.02 0.02 0.02 0.02 0.01 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 0.005 Elev 2.00 0.23 0.03 0.02 0.02 0.02 0.02 0.01 Route Time Series through Facility Inflow Time Series File:14690d.tsf Outflow Time Series File:rdout Inflow/Outflow Analysis Peak Inflow Discharge: Peak Outflow Discharge: Peak Reservoir Stage: Peak Reservoir Elev: Peak Reservoir Storage: 0.054 CFS at 0.000 CFS at 2 00 Ft 2 QQ Ft 216. Cu-Ft 0.005 Ac-Ft Flow Frequency Analysis Time Series File:rdout.tsf Project Location:Sea-Tac 0.420 0.441 0. 460 0.479 0. 497 0.515 0.532 0.548 0. 564 0.579 0.594 Storage 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 (Cu-Ft) (Ac-Ft) 216. 0.005 24. 0.001 3. 0.000 2. 0.000 2. 0.000 2. 0.000 2. 0.000 2. 0.000 100-yr Design 6:00 on Jan 9:00 on Jan 9 in Year 8 9 in Year 8 ---Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks --Rank Return Prob (CFS) (CFS) (ft) Period 0.000 6 2/09/01 2:00 0.000 2.00 1 100.00 0.990 0.000 8 1/05/02 16:00 0.000 0.23 2 25.00 0. 960 0.000 4 12/08/02 18:00 0.000 0.03 3 10.00 0.900 0.000 7 8/26/04 2:00 0.000 0.02 4 5.00 0.800 0.000 3 10/28/04 17:00 0.000 0.02 5 3.00 0.667 0.000 5 1/18/06 16:00 0.000 0.02 6 2.00 0.500 0.000 2 10/26/06 1:00 0.000 0.02 7 1.30 0.231 0.000 1 1/09/08 9:00 0.000 0.01 8 1.10 0.091 Computed Peaks 0.000 1. 41 50.00 0.980 f PLAN VIEW NTS 4" PVC PERFORATED PIPE V l,r-ROOF DRAIN YARD DRAIN OR CB SUMP WITH SOLID LID INFILTRATION TRENCH PLAN VIEW NTS ROOF DRAIN 4" PVC PERFORATED PIPE OVERFLOW SPLASH BLOCK WASHED ROCK , r-r 1-----'--=~LF PER 1,000 SQ. FT._---1 IMPERVIOUS SURFACE L_A ~~-:---5.0' MIN YARD DRAIN OR CB SUMP W/SOLID LID COMPACTED BACKFILL 4" PERF PIPE ,r -r WASHED ROCK INFILTRATION TRENCH DETAIL SECTION 5 CONVEYANCE SYSTEM ANALYSIS AND DESIGN NIA-No conveyance SECTION 6 SPECIAL REPORTS AND STUDIES Ph. 253-896-1011 Fx. 253-896-2633 WH Hughes Company, Inc. 14404 Issaquah-Hobart Road, Suite 104 Issaquah, Washington 98027 ( 425) 444-3367 Attn: Mr. Bill Hughes GeoResources, LLC 5007 Pacific Hwy. E, Suite 16 Fife, Washington 98424 April 23, 2015 Supplemental Letter -Infiltration Testing Proposed Short Plat NE 241" Street Renton, Washington PN: 813210 -0120 & -0130 Job No. WHHughes.NE24thSt.L We previously prepared a Geotechnical Engineering Report for the site dated December 11, 2014. On March 27, 2015 we returned to the site, monitored the excavation of two test pits and pertormed in-situ infiltration tests in general accordance with the EPA Falling Head Percolation Test Method (KCSWDM Section 5.4.1 }. Our supplemental test pits and infiltration testing were summarized in our March 31, 2015 Addendum Report. According to the KCSWDM Section C.2.2.2, infiltration devices are not allowed in critical areas buffers or on slopes steeper than 25 percent. The manual requires that for infiltration devices on slopes steeper than 15 percent or within 50 feet of a landslide hazard area or a steep slope hazard area, must be approved by a geotechnical engineer or engineering geologist. Based on an excerpt of the proposed site plan provided by Tom Redding, Encompass Engineering and Surveying, the proposed galleries for Lot 3 will be situated in areas of slopes as steep as 22 to 25 percent, with slopes of 25 to 28 percent located above the proposed gallery. Based on topographic information reviewed on the King Count iMap website and client provided site plans, the site slopes flatten offsite to the northwest. As currently proposed, the top of the gallery was to be about 6 inches below grade. Based on the site topography, we recommend that that the gallery be deepened so that the top of the gallery is 2 feet below grade. This will lower the bottom of the infiltration gallery to about elevation 268 or about the same elevation as the flatter, northwest corner of the parcel. ~ Given that the soils explored in our test pits consisted of a uniform sand and that the slopes flatten downslope of the galleries, it is our opinion that the proposed infiltrations on Lot 3 and Lot 2 can be constructed in the locations proposed with minimal impacts to the existing site slopes. • •• WrlHughes.NE24thSt.L(2).dac April 23, 2015 Page2 We have appreciated working for you on this project. Please do not hesitate to call at your earliest convenience if you have any questions or comments. Respectfully submitted, GeoResources, LLC KSS:DCB:kss KEITH scon SCHEMBS Keith S. Schembs, LEG Principal Doc ID: WHHughes.NE24thSt.L(2).doc Attachments: Site Plan Excerpt CC: Encompass Engineering and Surveying 165 NE Juniper Street, Suite 201 Issaquah, WA 98027 Attn: Mr. Tom Redding (425) 392-0250 Dana C. Biggerstaff, PE Principal 1f'Jf'.'.1v, / I 0 5 10 20 In~ I I --SCALE 1" = 20' EX. 6' WOOD FENCE LOT 14 162.62' ET HILLS G. 52 / 1 o· LOT 10 "W . . . 589"07'1...0 -·--=-'-JL-., ' -y . . 1.5 , · _ , / / _, i =rr -..::: -. .· ./ / ./ ,§> •. I ./' ,,,.-/ / __ _ -~ TT' R.: .2:,E / / . / .,, ~l.J_ __ ,,..c. __ , ________ ~--~-'.)t-,,;, / / / ---, 1· / ,., • j • -, / / / o..,., Z •\/ 0/~.· •' L, / / ,/ . /w/ '/ /1/ 7>: ~ 1 1 / ~ t' /'I· /L01:/~Jy . / / . . . . / I ZZ<v/ / .z . • . . VI '}W'fl --~ . / ' I • .,, ,' . / ' ) ' //' ///; y /J ,/ / ' ', / / / /, /'.: ./ /. . // ··:1 // / /Y7~LD lyi,N~~--~- / ,Zg / ~..£ .. wl, -~ / / '/ 500'2 ""-;_ IE=~.O± 1 .,, oo· ·· I • . ' 3 · . . ·' 89"07":zO W / ,E FENCE L0T1~ /1/ · a9·07:2o·w I / , 0' I ,'8,0 '/ i . ; 11 r I •/ / -"·'~ .-"' ---w-ecs , I I / /// // .1· o.s , /I . ' ' . i;: . FEI T . . 1 .. ::::H 'EXIS -/ •• J LCJ GA ./. 11:,,i.TR/ -- Ph. 253-896-1011 Fx. 253-896-2633 WH Hughes Company, Inc. 14404 Issaquah-Hobart Road, Suite 104 Issaquah, Washington 98027 ( 425) 444-3367 Mr. Bill Hughes GeoResources, LLC 5007 Pacific Hwy. E, Suite 16 Fife, Washington 98424 March 31, 2015 Addendum Letter· Infiltration Testing Proposed Short Plat NE 24th Street Renton, Washington PN: 813210 -0120 & ·0130 Job No. WHHughes.NE24thSt.L This letter summarizes the result of our recent infiltration testing for the proposed short plat site located on the above referenced parcels on NE 241h Street in Renton, Washington. We previously prepared a Geotechnical Engineering Report for the site dated December 11, 2014. On March 27, 2015 the owner excavated two additional test pits in the locations of the proposed infiltration galleries. The two supplemental explorations were excavated in the northwest corner (IT1) and near the center (IT2) of the project site, as shown on the attached Site Plan, Figure 1. We performed in-situ infiltration tests, as required by the City of Renton, in general accordance with the EPA Falling Head Percolation Test Method (KCSWDM Section 5.4.1). Our tests were performed at depths of approximately 6 to 12 inches at the bottom of the two test pits. The test pits were excavated to depths of 90 and 88 inches respectively. Based on our site observations and visual classifications in accordance with the USCS, it is our opinion the sandy soils observed in the November 24, 2014 test pits are representative of soils observed, classified in our previous test pits, summarized in our December 2014 report. However, during our recent site visit, we observed the surficial soils at IT2 appeared to have been reworked and contained fill, debris, and organics. Test pit logs of the two supplemental explorations are attached as Figure 2. During the presoak time, we noted that 12 inches of water completely drained within 10 minutes, therefore the prescribed 4-hour presoak was not required. During testing, water levels were filled to 6 inches above the bottom of the hole. IT1 has a measured infiltration rates of 17.6 inches per hour while IT2 had a measured rate of 16. 7 per hour. Using the simplified method outlined in Section 5.4.1 of the KCSWDM Section 5.4. 1, the design engineer should apply the following corrections factors: • F1e,ting = 0.30 for EPA Method • Fgeomet"' = determined by Civil Engineer • Fp1ugglng = 0.80 for fine sands and loamy sands We have prepared this report for WH Hughes Company, Inc. and other members of the design team for use in evaluating a portion of this project. Our report, conclusions and WHHughes.NE24thSt.lLa.doc March 31. 2015 Page 2 interpretations are based on data from our limited subsurface explorations and reconnaissance, and should not be construed as a warranty of the subsurface conditions. Variations in subsurface conditions are possible between the explorations and may also occur with time. A contingency for unanticipated conditions should be included in the budget and schedule. Sufficient monitoring, testing and consultation should be provided by our firm during construction to confirm that the conditions encountered are consistent with those indicated by the explorations, to provide recommendations for design changes should the conditions revealed during the work differ from those anticipated, and to evaluate whether installation activities comply with contract plans and specifications. Our recommendations are not intended to direct the contractor's methods, techniques, sequences or procedures, except as specifically described in our report for consideration in design. If there are any changes in the configurations or type of facilities to be constructed, the conclusions and recommendations presented in this report may not be fully applicable. If such changes are made, we should be given the opportunity to review our recommendations and provide written modifications or verifications, as appropriate . • • • We have appreciated working for you on this project. Please do not hesitate to call at your earliest convenience if you have any questions or comments. Respectfully submitted, GeoResources, LLC t/1 I --/ µ )VJ;~(7fr~ Dustin Taylor, EIT Staff Engineer in Training • y ,._ /i/zo1s KSS:BPB:kss KBTH SCOTI SCHEMBS Keith S. Schembs, LEG Principal Doc JD: WHHughes.NE24thSt.1La.doc Attachments: Figure 1 -Site Plan Figure 2 -Test Pit Logs BRADLEY P BIGGERSTAFF Brad P. Biggerstaff, LHG Principal I Approximate Site Location (rr,o.p created lrom the King County iMap http://ww1N5.kingcounty.gov/iMA?/) ~ i "'*'f " ---------------------- 1 GeoResources, LLC 5007 Pacific Highway East, Suite 16 Fife, Washington 98424 Phone: 253-896-1011 Fax: 253-896-2633 Site & Exploration Plan Proposed Short Plat NE 24'h Street Renton, WA Job: WHHughes.NE24thStF Nov 2014 ____________ _L_ _______ ~·------·-·-----·- Not to s_~~~ r-Figure~J Depth (feet) 0 % % 1 i/2 1Y, 6Y2 6V2 7V2 Depth (feet) 0 Y, Y, 2 2 7Y2 Soil Type SP SW SP Test Pit Log IT-1 Location: NW corner of back third lot Soil Description ----------------------------- Sod over Tops oil Orange brown fine to medium SAND with some silt to silty, trace roots (med dense. moist) Light brown coarse SAND (loose to med dense, moist) Light brown medium SAND with some gravel and trace silt (med dense, moist) Test pit terminated at about 7.5 foot below existing grade. No caving observed, No groundwater seepage observed. Test Pit Log IT-2 Location: NW corner of eastern front lot Soil Type Soil Description Sod over Topsoil SP Orange brown fine to medium SAND with some silt, trace roots (med dense, moist, reworked with some fill) SP Light brown medium SAND with trace silt and roots (med dense, moist) Test pit terminated at about 7.5 feet below existing grade. No caving observed, No groundwater seepage observed. Excavated on: March 27, 2015 Lonned bv: ORT GeoResources, LLC 5007 Pacific Highway East, Suite 16 Fife, Washington 98424 Phone: 253-896-1011 Fax: 253-896-2633 I ' Test Pit Logs Proposed Short Plat NE 24 1h Street Renton, WA J March2015 / --~-----~ Job: WHHughes.NE24thSt.F Figure 2 Ph 253-896-1011 Fx 253-896-2633 WH Hughes Company, Inc. 14404 Issaquah-Hobart Road, Suite 104 Issaquah, Washington 98027 ( 425) 444-3367 Mr. Bill Hughes GeoResources, LLC 5007 Pacific Hwy E., Ste. 16 Fife, Washington 98424 December 22, 2014 Geotechnical Engineering Report Proposed Short Plat NE 24'" Street Renton, Washington PN: 813210-0120 &-0130 Job No. WHHughes.NE24thSt.RG INTRODUCTION & SCOPE This report presents the results of our subsurface explorations, literature review, and engineering analysis and provides geotechnical design recommendations for the proposed short plat to be constructed on NE 24'" Street in Renton, Washington, as shown on Figure 1. The site is currently undeveloped. The short plat will consist of three residences, two that occupy the bottom two thirds of each parcel, and the third occupies the top one third of each parcel. The short plat will be accessed via three new driveways, two of the proposed driveways will extend north from NE 24th Street to the residences on the southern parcels, while the third driveway will extend between the two southern parcels back to the north lot. We anticipate that the residences will be 2-story, wood-framed structures supported on conventional spread and continuous concrete foundations. The remainder of the site will be covered with grass lawn and landscaping. Current site conditions and topography is included as Figure 2. The purpose of our services was to evaluate the surface and subsurface conditions at the site as a basis for developing and providing geotechnical engineering and stormwater management recommendations for the proposed development. Specifically, our scope of services for the project included the following: 1. Vistting the site and conducting a geologic reconnaissance to assess the site's soil, groundwater and slope conditions; 2. Exploring the subsurface conditions by excavating four test pits across the stte; 3. Addressing the City of Renton Critical Areas Ordinance for potential geological hazards; 4. Providing geotechnical design recommendations for foundation, floor slab, and pavement; and 5. Providing infiltration rates for the stormwater facility, as appropriate. WHHughes.NW24thSt.RG December 22, 2014 Page2 SITE CONDITIONS Surface Conditions The undeveloped parcels are located in an area of existing residential development. Both parcels are generally rectangular in shape, measure about 81 feet wide (east to west) by 155 feet deep (north to south) and encompass about 0.58 acres total. The site is bounded by existing residences on the west, north, and east and by NE 241" Street on the south. Site grades generally slope down from NE 24'" Street to the northwest. Current grades range from about 13 to 15 percent. Total vertical relief across the site is on the order of 30 feet. The approximate site topography, and contour lines obtained from the King County iMap website is shown on the attached Site & Exploration Plan, Figure 2. The site is currently undeveloped and is mostly covered with grass lawn and a few scattered trees. A fence separates the parcel into a front and rear yard area. Site Soils The USDA Natural Resource Conservation Service (NRCS) Web Soil Survey for King County maps the soils underlying the site to be the Indianola Loamy Sand (lnC) soils. The Indianola soils are derived from sandy glacial outwash and form on slopes of 6 to 15 percent. These soils are listed as having a "moderate" erosion hazard and are listed in hydrologic soils group A. A copy of the NRCS Soil Survey for the site area is attached as Figure 3. Geologic Conditions The Washington Interactive Geologic Map, Division of Geology and Earth Resources -Washington's Geological Survey maps the site as being underlain by a sequence of recessional outwash (Qgo) that was deposited during the most recent Vashon Stade of the Fraser Glaciation, approximately 12,000 to 15,000 years ago. The Recessional outwash consists of poorly stratified sand and gravel that was deposited ~Y meltwater streams and rivers emanating from the retreating glacial ice mass. The outwash is considered normally consolidated. An excerpt from the referenced map is included as Figure 4. Subsurface Conditions We evaluated subsurface conditions on November 24, 2014 by excavating a series of four test pits with a small track-mounted excavator working for GeoResources, LLC. The test pits extended to depths ranging from 7 to 7Y2 feet below the existing ground surface. The test pits were located in the field by our representative by pacing from existing site features. The approximate test pit locations are indicated on the attached Site Plan as Figure 2 and summarized below in Table 1. TABLE 1 APPROXIMATE LOCATIONS, ELEVATIONS, AND DEPTHS OF EXPLORATIONS Test Pit Surface Termination Termination Number Functional Location Elevation Depth Elevation (feet) (feet) (feet) TP-1 SW corner of proposed east front lot -302 7Y2 294Y2 TP-2 SW corner of proposed west front lot -292 7 285 TP-3 South of fence, between two front lots -290 7 283 TP-4 North of Qate to back lot -277 7 270 Elevation datum: King County iMap A geologist from our office continuously monitored the excavations, maintained WHHughes.NW24thSt.RG December 22, 2014 Page3 logs of the subsurface conditions encountered in each test pit, obtained representative soil samples, and observed pertinent site features. Representative soil samples obtained from the test pits were placed in sealed plastic bags and taken to our laboratory for further examination and testing, as deemed appropriate. Subsurface Conditions Our test pits encountered uniform subsurface conditions that generally confirmed the mapped stratigraphy. Our test pits encountered approximately 2 to 3 inches of topsoil/duff mantling a loose orange/brown fine to medium sand with some silt and roots/organics. Underlying these surficial soils, our test pits encountered a light brown medium course sand with a trace silt, the we interpret to be the mapped recessional outwash. The outwash was encountered to the full depth explored in all of our test pits. The subsurface conditions encountered in each test pit are described below in Table 2. TABLE2 APPROXIMATE THICKNESSES, DEPTHS, AND ELEVATIONS OF SOIL LAYERS ENCOUNTERED IN EXPLORATIONS Thickness of silty Depth to Elevation of Test Pit Thickness of Medium Dense Medium Dense Number Topsoil fine Sand Outwash Sand Outwash Sand (feet) (Weathered Outwash) (Outwash) (Outwash) (feet) (feet) (feel) TP-1 Y, 4 4Y2 297Y2 TP-2 v., 1 1 !f., 290¥., TP-3 % 114 2 288 TP-4 14 314 3Y2 273Y2 Elevation datum: King Countv iMao The soils encountered were visually classified in accordance with the Unified Soil Classification System (USCS) described on Figure 5. The test pit logs are included as Figures 6. Groundwater Conditions No groundwater seepage was encountered in our test pits at the time of digging. Based on the nature of the near surface soils, we anticipate fluctuations in the local groundwater levels will occur in response to precipitation patterns, off-site construction activities, and site utilization. CRITICAL AREA The City of Renton Critical Areas Ordinance (Ordinance 5137), Section JI, Chapter B, lists the various critical areas covered by Ordinance 5137, including: 1. Lands to Which These Regulations Apply: The following critical areas, classified in subsections H.1 through M.1 of this Section, are regulated by this section: a. Aquifer Protection Areas. b. Areas of Special Flood Hazard. c. Sensitive Slopes, twenty five percent (25%) to forty percent (40%) and Protected Slopes, forty percent (40%) or greater. d. Medium, High, and Very High Landslide Hazard Areas. WHHughes.NW24thSt.RG December 22, 2014 Page4 e. High Erosion Hazards. f. High Seismic Hazards. g. Medium and High Coal Mine Hazards. h. Volcanic Hazard Areas. i. Critical Habitats. j. Streams and Lakes. The Geologic Hazards defined by Ordinance 5137 are described in Section II, Chapter J, and include: Steep Slopes a. Steep Slopes: i. Steep Slope Delineation Procedure: The boundaries of a regulated steep sensitive or protected slope are determined to be in the location identified on the City of Renton's Steep Slope Atlas. An applicant's qualified professional may substitute boundaries independently derived from survey data for the City's consideration in determining the boundaries of sensitive or protected steep slopes. All topographic maps shall utilize two (2) foot contour intervals or the standard utilized in the City of Renton Steep Slope Atlas. ii. Steep Slope Types: (a) Sensitive Slopes. (b) Protected Slopes. The site slopes typically range from 13 to 15 percent across the site. In our opinion, the slopes do not meet the definition of a steep slope area. Landslide Hazards b. Landslide Hazards: i. Low Landslide Hazard (LL): Areas with slopes less than fifteen percent (15%). ii. Medium Landslide Hazard (LM): Areas with slopes between fifteen percent (15%) and forty percent {40%) and underlain by soils that consist largely of sand, gravel or glacial till. iii. High Landslide Hazards (LH): Areas with slopes greater than forty (40%), and areas with slopes between fifteen percent (15%) and forty percent (40%) and underlain by soils consisting largely of silt and clay. iv. Very High Landslide Hazards (LV): Areas of known mappable landslide deposits. No evidence of historic or active landslide activity was observed during or site visit, nor were any areas of landslide activity or mass wasting deposits shown on or within the vicinity of the site by the Washington Interactive Geologic Map. Given the mapped and observed site slopes, we would interpret the site to be a low landslide hazard area. Erosion Hazards c. Erosion Hazards: i. Low Erosion Hazard (EL): Areas with soils characterized by the Natural Resource Conservation Service (formerly U.S. Soil Conservation Service) as having slight or moderate erosion potential, and that slope less than fifteen percent (15%). WHHughes.NW24thSt.RG December 22, 2014 Pages ii. High .Erosion Hazard (EH): Areas with soils characterized by the Natural Resource Conservation Service (formerly U.S. Soil Conservation Service) as having severe or very severe erosion potential, and that slope more steeply than fifteen percent (15%). The NRCS Web Soil maps the soils underlying the site to be the Indianola loamy sand (lnC) soils. The Indianola soils are listed as having a "moderate" erosion hazard. Given the site slopes and mapped/encountered soil types, it is our opinion that the site has a Low Erosion Hazard. Seismic Hazards d. Seismic Hazards: i. Low Seismic Hazard (SL): Areas underlain by dense soils or bedrock. These soils generally have site coefficients of types S1 or S2, as defined in the Uniform Building Code. ii. High Seismic Hazard (SH): Areas underlain by soft or loose, saturated soils. These soils generally have site coefficients of types S3 or S4, as defined in the Uniform Building Code. Based on our observation and the subsurface units mapped at the site, we interpret the structural site conditions to correspond to a seismic Site Class "D" in accordance with Table 1613.5.2 in the 2012 IBC (International Building Code) documents. This is based on the likely range of equivalent SPT (Standard Penetration Test) blow counts for the soil types observed in the site area. These conditions were assumed to be representative for the conditions based on our experience in the vicinity of the site. Liquefaction is a phenomenon where there is a reduction or complete loss of soil strength due to an increase in pore water pressure. The increase in pore water pressure is induced by seismic vibrations. Liquefaction mainly affects geologically recent deposits of loose, fine-grained sands that are below the groundwater table. It is our opinion that the risk for liquefaction to occur at this site during an earthquake is negligible. Coal Mine Hazards e. Coal Mine Hazards: i. Low Coal Mine Hazards (CL): Areas with no known mine workings and no predicted subsidence. While no mines are known in these areas, undocumented mining is known to have occurred. ii. Medium Coal Mine Hazards (CM): Areas where mine workings are deeper than two hundred feet (200) for steeply dipping seams, or deeper than fifteen (15) times the thickness of the seam or workings for gently dipping seams. These areas may be affected by subsidence. iii. High Coal Mine Hazard (CH): Areas with abandoned and improperly sealed mine openings and areas underlain by mine workings shallower than two hundred feet (200) in depth for steeply dipping seams, or shallower than fifteen (15) times the thickness of the seam or workings for gently dipping seams. These areas may be affected by collapse or other subsidence. According to the published geologic maps, there is not known mine workings on or within the immediate vicinity of the site. Therefore, the site has low coal mine hazard rating. WHHughes.NW24thSt.RG December 22, 2014 Page 6 Volcanic Hazards f. Volcanic Hazards: Volcanic hazard areas are those areas subject to a potential for inundation from post lahar sedimentation along the lower Green River as identified in Plate II, Map D, in the report U.S. Department of the Interior, U.S. Geological Survey (Revised 1998). Volcano Hazards from Mount Rainier, Washington. Open-File Report 98-428. According to the Volcano hazards from Mount Rainier, Washington by Hoblitt, R. P.; Wilder, J. S.; Driedger, C. L.; Scott, K. M.; Pringle, P. T.; Vallance, J. W. (USGS Open- File Report: 98-428, revised 1998) the site is not listed within the Lower White and Green River lahar floodways. CONCLUSIONS AND RECOMMENDATIONS Based on the soils encountered in our explorations, laboratory analyses, and our engineering analysis, it is our opinion that the construction of the proposed short plat is feasible from a geotechnical engineering standpoint. Site Preparation and Grading All structural areas on the site to be graded should be stripped of vegetation, organic surface soils, and other deleterious materials. Organic topsoil will not be suitable for use as structural fill, but may be used for limited depths in non-structural areas. Based on the encountered subsurface conditions, stripping depths range from 3 to 12 inches. Where placement of fill material is required, the stripped/exposed subgrade areas should be compacted to a firm and unyielding surface prior to placement of any fill. Excavations for debris removal should be backfilled with structural fill compacted to the densities described in the "Structural Fill" section of this report. The exposed subgrade soil should be proof-rolled with heavy rubber-tired equipment during dry weather or probed with a 1/2-inch-diameter steel rod during wet weather conditions. Any soft, loose or otherwise unsuitable areas delineated during proof- rolling or probing should be recompacted, if practical, or over-excavated and replaced with structural fill. Structural Fill Structural fill should be placed in horizontal lifts of appropriate thickness to allow adequate and uniform compaction of each lift. Fill should be compacted to at least 95 percent of MDD (maximum dry density as determined in accordance with ASTM D-1557). The appropriate lift thickness will depend on the fill characteristics and compaction equipment use, but is typically limited to 8 inches. The suitability of material for use as structural fill will depend on the gradation and moisture content of the soil. As the amount of fines (material passing US No. 200 sieve) increases, soil becomes increasingly sensitive to small changes in moisture content and adequate compaction becomes more difficult to achieve. During wet weather, we recommend use of well-graded sand and gravel with less than 5 percent {by weight) passing the US No. 200 sieve based on that fraction passing the 3/4-inch sieve, such as "Gravel Backfill tor Walls' (9-03.12(2)). If prolonged dry weather prevails during the earthwork and foundation installation phase of construction, higher fines content (up to 10 to 12 percent) will be acceptable. Material placed for structural fill should be free of debris, organic matter, trash and cobbles greater than 6-inches in diameter. The moisture content of the fill material should be adjusted as necessary for proper compaction. WHHughes.NW24thSt.RG December 22, 2014 Page? Suitability of On-Site Materials as Fill During dry weather construction, any non-organic on-site soil may be considered for use as structural fill; provided it meets the criteria described above in the "Structural Fill" section and can be compacted as recommended. If the soil material is over-optimum in moisture content when excavated, it will be necessary to aerate or dry the soil prior to placement as structural fill. The native outwash sand has a low amount of fines content and will be suitable to use as fill during a wide range of moisture conditions. However, we do expect that the soil will become difficult to reuse as structural fill during extended periods of wet weather or when the soil is work at 3 percent or more above optimum moisture content. We recommend that completed graded-areas be restricted from traffic or protected prior to wet weather conditions. The graded areas may be protected by paving, placing asphalt-treated base, a layer of free-draining material such as pit run sand and gravel or clean crushed rock material containing less than 5 percent fines, or some combination of the above. Foundation Support Based on the subsurface soil conditions encountered in our test pits, we anticipate that the residences will be supported on the native outwash soils. We recommend a minimum width of 18 inches for isolated footings and at least 12 inches for single story or 16 inches multi-story structures for continuous wall footings. All footing elements should be embedded at least 18 inches below grade for frost protection. Footings founded as described above can be designed using an allowable soil bearing capacity of 2,000 psf (pounds per square foot) for combined dead and long-term live loads. The weight of the footing and any overlying backfill may be neglected. The allowable bearing value may be increased by one-third for transient loads such as those induced by seismic events or wind loads. Lateral loads may be resisted by friction on the base of footings and floor slabs and as passive pressure on the sides of footings. We recommend that an allowable coefficient of friction of 0.30 be used to calculate friction between the concrete and the underlying native outwash. Passive pressure may be determined using an allowable equivalent fluid density of 300 pcf (pounds per cubic foot). Factors of safety have been applied to these values. We estimate that settlements of footings designed and constructed as recommended will be less than 1 inch, for the anticipated load conditions, with differential settlements between comparably loaded footings approach total settlements. Most of the settlements should occur essentially as loads are being applied. However, disturbance of the foundation subgrade during construction could result in larger settlements than predicted. We recommend that all foundations be provided with footing drains. Floor Slab Support Slab-on-grade floors, where constructed, should be supported on the native outwash or properly placed and compacted structural fill. We recommend that floor slabs be directly underlain by a minimum 4-inch thickness capillary break material such as pea gravel, or Gravel Backfill for Drains (WSDOT 9-03.1214). The capillary break material should be placed in one lift and compacted to an unyielding condition. A synthetic vapor barrier is recommended to control moisture migration through the slabs. This is of particular importance where the foundation elements are underlain by the silty till, or where moisture migration through the slab is an issue, such as where adhesives are used to anchor carpet or tile to the slab. WHHughes.NW24thS1.RG December 22, 2014 Page 9 We trust this is sufficient for your current needs. Should you have any questions, or require additional information, please contact us at your earliest convenience. Respectfully submitted, GeoResources, LLC KSS:DCB:kss Keith S. Schembs, LEG Principal DoclD: WHHughes.NW24thSt.RG Attachments: Figure 1: Site Vicinity Map Figure 2: Site and Exploration Map Figure 3: USDA Soil Map Figure 4: USGS Geologic Map Figure 5: Unified Soil Classification System Figure 5: Test Pit Logs Dana C. Biggerstaff, PE Senior Geotechnical Engineer g < 1 t#/d9R•li~orrldtu .. ·l _ ~'lDT_~~ ..... .,·-- . ii' NJIST"Sf ke Washington ·• ·~ f /l ·1·' · ... Approximate Site Location (map created from the King County iMap http://www5.kingcounty.gov/iMAP/) GeoResources, LLC 5007 Pacific Highway East, Suite 16 Fife, Washington 98424 Phone: 253-896-1 011 Fax: 253-896-2633 Site Location Map Proposed Short Plat NE 241h Street Renton, WA Job: WHHughes.NE24thSt.F Nov 2014 = .. . ·-____ Mii2Anf NC Not to Scale Figure 1 i ' t ~:-----..: ' ! . • ,I,; ',: : ,, • '': ' • I • ' ' ' ~ Approximate Site Location (map created from the King County iMap http://wwwS.kingcounty.gov/iMAP/) GeoResources, LLC 5007 Pacific Highway East, Suite 16 Fife, Washington 98424 Phone: 253-896-1011 Fax: 253-896-2633 Site & Exploration Plan Proposed Short Plat NE 241h Street Renton, WA Job: WHHughes.NE24thSt.F I Nov 2014 Not to Scale I Figure 2 Soil · T ,pe ApproximateSite Location (Soils Map created from NRCS Web Soil Survey l1ttp://websoilsurvey.sc.egov.usda.gov) Soil Name Parent Materiai Slopes , I Erosion Hazard Hydrologic I Soils Group lnC 1 Indianola Loamy Sand Sandy Glacial Outwash 6 -15 j Moderate A / ---~---_:_ ________ ------_L ________ __.c _____ ~ GeoResources, LLC 5007 Pacific Highway East. Suite 16 Fife, Washington 98424 Phone: 253-896-1011 Fax: 253-896-2633 NRCS Soils Map Proposed Short Plat NE 24th Street Renton, WA Job: WHHughes.NE24thSt.F Nov 2014 Not to Scale Figure 3 • \ ' ~· ~ - ; . ~ .. " ' .. '• Qgo Approximate Site Location (excerpt of the Washington Interactive Geologic Map https://fortress.wa.gov/dnr/geology/) D Qgo -Continental Glacial Outwash, Fraser Age GeoResources, LLC 5007 Pacific Highway East, Suite 16 Fife, Washington 98424 Phone: 253-896-1011 Fax: 253-896-2633 USGS Geologic Map Proposed Short Plat NE 24'h Street Renton, WA Job: WHHughes.NE24thSt.F Nov 2014 Not to Scafe Figure 4 SOIL CLASSIFICATION SYSTEM MAJOR DIVISIONS GROUP GROUP NAME SYMBOL GRAVEL CLEAN GW WELL-GRADED GRAVEL, FINE TO COARSE GRAVEL GRAVEL COARSE GP POORLY-GRADED GRAVEL GRAINED More than 50% SOILS Of Coarse Fraction GRAVEL GM SIL TY GRAVEL Retained on No. 4Sieve WITH FINES GC CLAYEY GRAVEL More than 50% SAND CLEAN SAND SW WELL-GRADED SAND, FINE TO COARSE SAND Retained on No. 200 Sieve SP POORLY-GRADED SAND More than 50% Of Coarse Fraction SAND SM SILTY SAND Passes WITH FINES No. 4Sieve SC CLAYEY SAND SILT AND CLAY INORGANIC ML SILT FINE GRAINED CL CLAY SOILS Llquld Limit Less than 50 ORGANIC OL ORGANIC SILT, ORGANIC CLAY SILT AND CLAY INORGANIC MH SILT OF HIGH PLASTICITY, ELASTIC SILT More than 50% Passes CH CLAY OF HIGH PLASTICITY, FAT CLAY No. 200 Sieve Liquid Limit 50 or more ORGANIC OH ORGANIC CLAY, ORGANIC SILT HIGHLY ORGANIC SOILS PT PEAT NOTES: SOIL MOISTURE MODIFIERS: 1. Field classification is based on visual examination of soil Dry-Absence of moisture, dry to the touch in general accordance with ASTM D2488-90. Moist-Damp, but no visible water 2. Soi! classification using laboratory tests is based on ASTM D2487-90. Wet-Visible free water or saturated, usually soil is obtained from below water table 3. Description of soil density or consistency are based on interpretation of blow count data, visual appearance of soils, and or test data. GeoResources, LLC Soil Classification System 5007 Pacific Highway East, Suite 16 Proposed Short Plat Fife, Washington 98424 NE 241h Street Phone: 253-896-1011 Renton, WA Fax: 253-896-2633 Job: WHHughes.NE24thSt.F I Nov 2014 I Figure 5 Depth (feet) 0 -v, V, -4Y2 4Y.e -6Y2 6Y2 -7¥., Depth (feet) 0 -v., Y2 -1¥., 1V, 7 Depth (feet) 0 -% % -2 2 7 Depth (feet) 0 -,. ,. -1V2 1 Me -2 2 -3¥.a 311, -7 Soil Type - SP SW SP Test Pit Log TP-1 Location: SW corner of eastern front lot Soil Description Sod over Topsoil Light orange brown fine to medium SAND with some silt to silty, trace roots (med dense, moist) Light brown coarse SAND, with some gravel (loose to med dense, moist) Light brown medium SAND with trace silt (med dense, moist) Test pit terminated at about 7 foot below existing grade. Slight caving observed from 4 to 6 ft, No groundwater seepage observed Test Pit Log TP-2 Location: SW corner of western front lot Soil Type Soil Description -Sod over Topsoil SP Light orange brown fine to medium SAND with som_e silt to silty, trace roots (med dense, moist) SP Light brown medium SAND with trace silt (med dense, moist) Soil Type SP SP Soil Type - SP - SP SP Test pit terminated at about 7 feet below existing grade. No caving observed, No groundwater seepage observed Test Pit Log TP-3 Location: South of fence, between two front lots Soil Description Sod over Topsoil Orange brown fine to medium SAND with trace to some silt, trace roots (med dense, moist) Light brown medium SAND with trace silt (med dense, moist) Test pit terminated at about 7 foot below existing grade. No caving observed, No groundwater seepage observed Test Pit Log TP-4 Location: North of gate to back third lot Soil Description Sod over Topsoil Orange brown fine to medium SAND with some silt to silty, trace roots (med dense, moist) Relict Topsoil Light orange brown fine to medium SAND with trace to some silt, trace roots (med dense, moist) Light brown medium SAND with trace silt (med dense, moist) Test pit terminated at about 7 feet below existing grade. No caving observed, No groundwater seepage observed Excavated on: Nov 24, 2014 Loaaed by: KSS GeoResources, LLC 5007 Pacific Highway East, Suite 16 Fife, Washington 98424 Phone: 253-896-1011 Fax: 253-896-2633 I Test Pit Logs Proposed Short Plat NE 241h Street Renton, WA Job: WHHughes.NE24thS1.F I Nov 2014 I Figure 6 SECTION 7 OTHER PERMITS SECTION 8 ESC ANALYSIS AND DESIGN Encompass Engineering & Surveying Eastern Washington Division 407 Swiftwater Blvd., Cle Elum, WA 98922 Phone (509) 674-7433 Fax (509) 674-7419 Western Washington Division 165 NE Juniper St .• Suite 201, Issaquah, WA 98027 Phone (425) 382-0250 Fax (425) 391-3055 {/,J( (;,l.,- SHEET NO.-----------OF ________ _ CALCULATED BY---------DATE -------- CHECKED BY __________ DATE-------- SCALE ---------------------- ... ---ene. rt~f.-! SECTION 9 BOND QUANTITIES, FACILITY SUM:MARIES, AND DECLARATION OF COVENANT Site Improvement Bond Quantity Worksheet S15 Web date: 0410312015 tQ King County Department of Permitting & Environmental Review 35030 SE Douglas Street, Suite 210 Snoqualmie, Washington 98065-9266 206-296-6600 TTY Relay 711 Project Name: NE 24th 3-Lot Short Plat Location: Clearing greater than or equal to 5,000 board feet of timber? ______ yes If yes, Forest Practice Permit Number: (RCW 76.09) Page 1 of 9 _x __ no Site Improvement Bond Quantity Worksheet 2015.xls For alternate formats, call 206-296-6600. Date: 5/21/2015 Project No.: Activity No.: Note: All prices include labor, equipment, materials, overhead and profit. Prices are from RS Means data adjusted for the Seattle area or from local sources if not included in the RS Means database. Unit prices updated: 3/2/2015 Version: 3/2/2015 Report Date: 5/21/2015 Site Improvement Bond Quantity Worksheet S15 Web date 04/0312015 Reference# EROSION/SEDIMENT CONTROL Number Backfill & compaction-embankment ESC-1 Check dams, 4" minus rock ESC-2 SWDM 5.4.6.3 Crushed surfacing 1 1/4" minus ESC-3 WSDOT 9-03.9(3) Ditching ESC-4 Excavation-bulk ESC-5 Fence, silt ESC-6 SWDM 5.4.3.1 Fence, Temporary (NGPE) ESC-7 Hydroseeding ESC-8 SWDM 5.4.2.4 Jute Mesh ESC-9 SWDM 5.4.2.2 Mulch, by hand, straw, 3" deep ESC-10 SWDM 5.4.2.1 Mulch, bv machine, straw, 2" deep ESC-11 SWDM 5.4.2.1 Pipinq, temporary, CPP, 6" ESC-12 Piping, temporary, CPP, 8" ESC-13 Piping, temporary, CPP, 12" ESC-14 Plastic covering, 6mm thick, sandbagged ESC-15 SWDM 5.4.2.3 Rip Rap, machine placed; slopes ESC-16 WSDOT 9-13.1(2) Rock Construction Entrance, 50'x15'x1' ESC-17 SWDM 5.4.4.1 Rock Construction Entrance, 100'x15'x1' ESC-18 SWDM 5.4.4.1 Sediment pond riser assembly ESC-19 SWDM 5.4.5.2 Sediment trap, 5' high berm ESC-20 SWDM 5.4.5.1 Sed. trap, 5' high, riprapped spillway berm section ESC-21 SWDM 5.4.5.1 Seeding, by hand ESC-22 SWDM 5.4.2.4 Sodding, 1" deep, level ground ESC-23 SWDM 5.4.2.5 Sodding, 1" deep, sloped ground ESC-24 SWDM 5.4.2.5 TESC Supervisor ESC-25 Water truck, dust control ESC-26 SWDM 5.4.7 WRITE-IN-ITEMS -lsee oane 91 Page 2 of 9 Site Improvement Bond Quantity Worksheet 2015.xls Unit Price Unit Quantitv $ 6.00 CY $ 80.00 Each $ 95.00 CY $ 9.00 CY $ 2.00 CY 150 $ 1.50 LF $ 1.50 LF 470 $ 0.80 SY $ 3.50 SY $ 2.50 SY $ 2.00 SY 500 $ 12.00 LF $ 14.00 LF $ 18.00 LF $ 4.00 SY $ 45.00 CY $ 1,800.00 Each 1 $ 3,200.00 Each $ 2,200.00 Each $ 19.00 LF $ 70.00 LF $ 1.00 SY $ 8.00 SY $ 10.00 SY $ 110.00 HR $ 140.00 HR Each ESC SUBTOTAL: 30% CONTINGENCY & MOBILIZATION: ESCTOTAL: COLUMN: #of Applications Cost 1 300 1 705 1 1000 1 1800 $ 3,805.00 $ 1,141.50 $ 4,946.50 A Unit prices updated: 3/2/2015 Version: 3/2/2015 Report Date: 5/21/2015 Site Improvement Bond Quantity Worksheet Existing Future Public 1 Right-of-Way Right of Way & Drainage Facilities Unit Price Unit Quant. Cost Quant. Cost Quant. GENERAL ITEMS No. Backfill & Compaction-embankment GI -1 $ 6.00 CY Backfill & Compaction-trench GI -2 $ 9.00 CY Clear/Remove Brush, bv hand GI -3 $ 1.00 SY Clearina/Grubbina/Tree Removal GI -4 $10,000.00 Acre Excavation -bulk GI -5 $ 2.00 CY Excavation -Trench GI -6 $ 5.00 CY FencinQ, cedar, 6' hi!::lh GI -7 $ 20.00 LF Fencina, chain link, vinvl coated, 6' hiqh GI -8 $ 20.00 LF Fencina, chain link, aate, vinvl coated, 2 GI -9 $ 1,400.00 Each Fencina, solit rail, 3' hiah GI -10 $ 15.00 LF Fill & compact -common barrow GI -11 $ 25.00 CY Fill & compact -gravel base GI -12 $ 27.00 CY Fill & compact -screened topsoil GI -13 $ 39.00 CY Gabion, 12" deep, stone filled mesh GI -14 $ 65.00 SY Gabion, 18" deep, stone filled mesh GI -15 $ 90.00 SY Gabion, 36" deeo, stone filled mesh GI -16 $ 150.00 SY Grading, fine, by hand GI -17 $ 2.50 SY GradinQ, fine, with r::irader GI -18 $ 2.00 SY Monuments, 3' Iona GI -19 $ 250.00 Each Sensitive Areas Sian GI -20 $ 7.00 Each Soddina, 1" deeo, slooed around GI -21 $ 8.00 SY Surveying, line & grade GI -22 $ 850.00 Day SurvevinQ, lot location/lines GI -23 $ 1,800.00 Acre 0.58 Traffic control crew ( 2 flanners ) GI -24 $ 120.00 HR Trail, 4" chipped wood GI -25 $ 8.00 SY Trail, 4" crushed cinder GI -26 $ 9.00 SY Trail, 4" top course GI -27 $ 12.00 SY Wall, retaininq, concrete GI -28 $ 55.00 SF Wall, rockery GI -29 $ 15.00 SF Page 3 of:9 SUBTOTAL *KCC 27 A authorizes only one bond reduction. Site Improvement Bond Quantity Worksheet 2015.xls Web date: 04/03/2015 , Private Improvements Cost 1,044.00 1,044.00 Unit prices updated: 0310212015 Version: 0310212015 Report Date: 512112015 Site Improvement Bond Quantity Worksheet Existing Future Public Right-of-way Right of Way & Drainage Facilities I Unit Price Unit Quant. I Cost Quant. Cost· Quant. I ROAD IMPROVEMENT No. AC Grindino, 4' wide machine< 1000sv RI -1 $ 30.00 SY AC GrindinQ, 4' wide machine 1000-2000 RI -2 $ 16.00 SY AC Grindinq, 4' wide machine > 2000sv RI -3 $ 10.00 SY AC Removal/Disoosal Rl-4 $ 35.00 SY Barricade, tvpe Ill ( Permanent ) RI -6 $ 56.00 LF Curb & Gutter, rolled Rl-7 $ 17.00 LF Curb & Gutter, vertical Rl-8 $ 12.50 LF 35 437.50 Curb and Gutter, demolition and disposal RI -9 $ 18.00 LF 35 630.00 Curb, extruded asphalt RI -10 $ 5.50 LF Curb, extruded concrete RI -11 $ 7.00 LF Sawcut, asphalt, 3" depth RI -12 $ 1.85 LF 100 185.00 Sawcut, concrete, per 1" depth RI -13 $ 3.00 LF Sealant, asnhalt RI -14 $ 2.00 LF 100 200.00 Shoulder, AC, ( see AC road unit price) RI -15 $ -SY Shoulder, qravel, 4" thick RI -16 $ 15.00 SY Sidewalk, 4" thick RI -17 $ 38.00 SY 30 1,140.00 Sidewalk, 4" thick, demolition and dispos RI -18 $ 32.00 SY Sidewalk, 5" thick RI -19 $ 41.00 SY 30 1,230.00 Sidewalk, 5" thick, demolition and dispose RI -20 $ 40.00 SY Sion, handicap RI -21 $ 85.00 Each Strioina, oer stall RI -22 $ 7.00 Each Stripina, them,oplastic, ( for crosswalk) RI -23 $ 3.00 SF Striping, 4" reflectorized line RI -24 $ 0.50 LF Page4of9 SUBTOTAL 3.822.50 "KCC 27 A authorizes only one bond reduction. Site Improvement Bond Quantity Worksheet 2015.xls Web date: 04/03/2015 Private Improvements ' Cost Unit prices updated: 0310212015 Version: 0310212015 Report Date: 512112015 Site Improvement Bond Quantity Worksheet Web date: 04/03/2015 Unit Price ROAD SURFACING No. Additional 2.5" Crushed Surfacing RS-1 $ 3.60 HMA 112"" Overlay, 1.5" RS-2 $ 14.00 HMA 112'' Overlay 2" RS-3 $ 18.00 HMA Road, 2", 4" rock, First 2500 SY RS-4 $ 28.00 HMA Road, 2", 4" rock, Qtv. over 2500 S' RS-5 $ 21.00 HMA Road, 3", 9 112" Rock, First 2500 S' RS-6 $ 35.00 HMA Road, 3", 9 112" Rock, Qty Over 25 RS-7 $ 42.00 Not Used RS-8 Not Used RS-9 HMA Road, 6" Depth, First 2500 SY RS-10 $ 33.10 HMA Road, 6" Depth, Qtv. Over 2500 SY RS-11 $ 30.00 HMA 314" or 1", 4" Depth RS-12 $ 20.00 Gravel Road, 4" rock, First 2500 SY RS-13 $ 15.00 Gravel Road, 4" rock, Otv. over 2500 SY RS-14 $ 10.00 PCC Road (Add Under Write-Ins w/Desio RS-15 Thickened Edge RS-17 $ 8.60 Page 5 of9 SUBTOTAL *KCC 27A authorizes only one bond reduction. Site Improvement Bond Quantity Worksheet 2015.xls Unit SY SY SY SY SY SY SY SY SY SY SY SY LF Existing Future Public Private Right.of-way Right of Way Improvements & Drainage Facilities Quant. I Cost Quant. I Cost Quant. Cost /4" Rock -2.5 base & 1.5" to course 9 1/2" Rock-8" base & 1.5" too course) 20 560.00 180 560.00 5.040.00 5,040.00 Unit prices updated: 03/02/2015 Version: 03/02/2015 Report Date: 5/21/2015 Site Improvement Bond Quantity Worksheet Web date: 04/0312015 Unit Price Unit DRAINAGE (CPP = Corrugated Plastic Pipe, N12 or Equivalent) Access Road, RID D -1 $ 21.00 SY Bollards -fixed D-2 $ 240.74 Each Bollards -removable D-3 $ 452.34 Each "'(CBs include frame and lid) CB Tvpe I D-4 $ 1,500.00 Each CB Tvoe IL D-5 $ 1,750.00 Each CB Type II, 48" diameter D-6 $ 2,300.00 Each for additional depth over 4' D-7 $ 480.00 FT CB Tvpe II, 54" diameter D-8 $ 2,500.00 Each for additional depth over 4' D-9 $ 495.00 FT CB Tvpe II, 60" diameter D -10 $ 2,800.00 Each for additional depth over 4' D -11 $ 600.00 FT CB Type II, 72" diameter D-12 $ 3,600.00 Each for additional depth over 4' D-13 $ 850.00 FT Throuah-curb Inlet Framework (Add) D-14 $ 400.00 Each Cleanout, PVC, 4" D-15 $ 150.00 Each Cleanout, PVC, 6" D-16 $ 170.00 Each Cleanout, PVC, 8" D-17 $ 200.00 Each Culvert, PVC, 4" D-18 $ 10.00 LF Culvert, PVC, 6" D -19 $ 13.00 LF Culvert, PVC, 8" D-20 $ 15.00 LF Culvert, PVC, 12" D -21 $ 23.00 LF Culvert, CMP, 8" D -22 $ 19.00 LF Culvert, CMP, 12" D -23 $ 29.00 LF Culvert, CMP, 15" D -24 $ 35.00 LF Culvert, CMP, 18" D -25 $ 41.00 LF Culvert, CMP, 24" D -26 $ 56.00 LF Culvert, CMP, 30" D -27 $ 78.00 LF Culvert, CMP, 36" D -28 $ 130.00 LF Culvert, CMP, _4ai. D -29 $ 190.00 LF Culvert, CMP, 60" D -30 $ 270.00 LF Culvert, CMP,72" D -31 $ 350.00 LF Page 6 of 9 SUBTOTAL *KCC 27 A authorizes only one bond reduction. Site Improvement Bond Quantity Worksheet 2015.xls Existing Future Public Private Right-of-way Right of Way Improvements & Drainage Facilities Quant. Cost Quant. I Cost Quant. I Cost For Culvert orices, Averaae of 4' cover was assumed. Assume perforated PVC is same price as solid pipe. 3 1 138 ' ' I ! . ' 4,500.00 170.00 2,070.00 6/40.00 Unit prices updated: 03/02/2015 Version: 03/02/2015 Report Date: 5/21/2015 Site Improvement Bond Quantity Worksheet Existing Future Public Right-of-way Right of Way DRAINAGE CONTINUED & Drainage Facilities No. Unit Price Unit Quant. Cost Quant. Cost Quant. Culvert, Concrete. 8" D -32 $ 25.00 LF Culvert. Concrete, 12" D-33 $ 36.00 LF Culvert, Concrete, 15" D-34 $ 42.00 LF Culvert, Concrete, 18" D -35 $ 48.00 LF Culvert. Concrete, 24" D-36 $ 78.00 LF Culvert, Concrete, 30" D-37 $ 125.00 LF Culvert, Concrete. 36" D -38 $ 150.00 LF Culvert, Concrete, 42" D-39 $ 175.00 LF Culvert, Concrete, 48" D-40 $ 205.00 LF Culvert, CPP, 6" D-41 $ 14.00 LF Culvert, CPP, B" D-42 $ 16.00 LF Culvert, CPP, 12" D-43 $ 24.00 LF Culvert. CPP, 15" D-44 $ 35.00 LF Culvert, CPP, 18" D-45 $ 41.00 LF Culvert, CPP, 24" D-46 $ 56.00 LF Culvert, CPP, 30" D-47 $ 78.00 LF Culvert, CPP, 36" D-48 $ 130.00 LF Ditchina D -49 $ 9.50 CY Flow Dispersal Trench (1,436 base+) D-50 $ 28.00 LF French Drain (3' depth) D -51 $ 26.00 LF Geotextile, laid in trench, polypropylene D-52 $ 3.00 SY Mid-tank Access Riser, 48" dia, 6' deep D-54 $ 2,000.00 Each Pond Overflow Spillway D -55 $ 16.00 SY Restrictor/Oil Separator, 12" D -56 $ 1,150.00 Each Restrictor/Oil Seoarator, 15" D -57 $ 1,350.00 Each Restrictor/Oil Separator, 18" D -58 $ 1,700.00 Each Riprap, placed D -59 $ 42.00 CY Tank End Reducer (36" diameter) D -60 $ 1,200.00 Each Trash Rack, 12" D -61 $ 350.00 Each Trash Rack, 15" D -62 $ 410.00 Each Trash Rack, 18" D -63 $ 480.00 Each Trash Rack, 21" D -64 $ 550.00 Each Page 7 of9 SUBTOTAL *KCC 27A authorizes only one bond reduction. Site Improvement Bond Quantity Worksheet 2015.xls Web date: 04/03/2015 Private Improvements Cost . Unit prices updated: 0310212015 Version: 0310212015 Report Date: 512112015 Site Improvement Bond Quantity Worksheet Web date· 04/0312015 I Unit Price Unit PARKING LOT SURFACING No. 2" AC, 2" top course rock & 4" borrow PL -1 $ 21.00 SY 2" AC, 1.5" lop course & 2.5" base cour~ PL-2 $ 28.00 SY 4" select borrow PL-3 $ 5.00 SY 1.5" top course rock & 2.5" base course PL-4 $ 14.00 SY UTILITY POLES & STREET LIGHTING Utility Pole(s) Relocation UP-1 Lump Sum Street Lioht Poles w/Luminaires UP-2 Each WRITE-IN-ITEMS Such as detention/water Quality vaults.) No. Relocated Street Lioht WI -1 $ 2,500.00 Each Wl-2 SY Wl-3 CY Infiltration Trench Wl-4 $ 50.00 LF Wl-5 FT Wl-6 Wl-7 Wl-8 Wl-9 Wl-10 SUBTOTAL SUBTOTAL (SUM ALL PAGES): 30% CONTINGENCY & MOBILIZATION: GRANDTOTAL: COLUMN: Page8of9 *KCC 27A authorizes only one bond reduction. Site Improvement Bond Quantity Worksheet 2015.xls Existing Future Public Private Right-of-way Right of Way Improvements & Drainaae Facilities Quant. I Price Quant. Cost Quant. I Cost Not To Be Used For Roads Or Shoulders NA NA NA NA NA NA NA NA Utilitv oole relocation costs must be accomoanied bv Franchise Utilitv's Cost Estimate 1 2500 23 2,500.00 6,882.50 2,064.75 8,947.25 B C I 1,150.00 1,150.00 13,974.00 4,192.20 18,166.20 D Unit prices updated 03/02/2015 Version 03/02/2015 Report Date: 5/21/2015 site Improvement Bond Quantity worksneet 01/12/15 Original bond computations prepared by: Name:----------------------------------- PE Registration Number: ------------------------------ Firm Name: ----------------------------------- Address: Date: '.'.e> t 26 JI.:_;- Tel#: ------ Project#: ROAD IMPROVEMENTS & DRAINAGE FACILITIES FINANCIAL GUARANTEE REQUIREMENTS PERFORMANCE BOND* I BOND* AMOUNT PUBLIC ROAD & DRAINAGE AMOUNT REQUIRED AT RECORDING MAINTENANCE/DEFECT BOND* OR TEMP OCCUPANCY*** Stabilization/Erosion Sediment Control (ESC) Existing Right-of-Way lmprovments Future Public Right-of-Way Drainage Facilities (Pond/Bioswale/Vaults,etc) Private Improvements Calculated Quantity Completed Total Right-of-Way and/or Site Restoration (A) $ '::l,,9'{b , 5°C, (B) $ ~,qi.(, . 2 ~ (C,) $ _____ _ (C,) $ _____ _ (D) $ IS,,166. LO (A+B) s (3.P:83 .,5 Performance Bond* Amount (A+B+C,)xl.5 = Total l(T) $ 2.0.2,L/0 . 63 Maintenance/Defect Bond* Total NAME OF PERSON PREPARING BOND* REDUCTION: ------------------ *NOTE: The word "Bond" as used in this document means a financial guarantee acceptable to the City of Renton. 0 NOTE: Right-of-way and site restoration bonds to be combined when both are required. (B+C+Public Portion of C,) x 0.2 =$ _____ _ DATE: -------- The restoration requirement shall include the total cost for all TESC as a minimum, not a maximum. In addition, corrective work, both on-and off-site needs to be included. Quantities shall reflect worse case scenarios, not just minimum requirements. For example, if a salmonid stream may be damaged, some estimated costs for restoration needs to be reflected in this amount. Required Bond• Amounts Are Subject to Review and Modifications by COR. I ' -SECTION 10 OPERATIONS AND MAINTENANCE MANUAL • C.2.2.6 MAINTENANCE INSTRUCTIONS FOR FULL INFILTRATION If the full infiltration flow control BMP is proposed for a project, the following 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. 1.3.3 (p. C-18). The intent of these instructions is to explain to furore property owners, the purpose of the BMP and how it must be maintained and operated. These instructions are intended to be a minimum; DDES may require additional instructions based on site- specific conditions. Also, as the County gains more experience with the maintenance and operation of these BMPs, future updates to the instructions will be posted on King County's Swface Water Design Manual website. CJ TEXT OF INSTRUCTIONS Your property contains a stormwater management flow control BMP (best management practice) called "full infiltration," which was installed to mitigate the stormwater quantity and quality impacts of some or all of the impervious surfaces on your property. Full infiltration is a method of soaking runoff from 1mperv1ous area (such as paved areas and roofs) into the ground. If properly installed and maintained, full infiltration can manage runoff so that a majority of precipitation events are absorbed. Infiltration devices, such as gravel filled trenches, drywells, and ground surface depressions, facilitate this process by putting runoff in direct contact with the soil and holding the runoff long enough to soak most of it into the ground. To be successful, the soil condition around the infiltration device must be reliably able to soak water into the ground for a reasonable number of years. The infiltration devices used on your property include the following as indicated on the flow control BMP site plan: D gravel filled trenches, D drywells, D ground surface depressions. The size, placement, and composition of these devices as depicted by the flow control BMP site plan and design details must be maintained and may not be changed without written approval either from the King County Water and Land Resources Division or through a future development permit from King County. Infiltration devices must be inspected annually and after major storm events to identify and repair any physical defects. Maintenance and operation of the system should focus on ensuring the system's viability by preventing sediment-laden flows from entering the device. Excessive sedimentation will result in a plugged or non-functioning facility. If the infiltration device has a catch basin, sediment accumulation must be removed on a yearly basis or more frequently if necessary. Prolonged ponding around or atop a device may indicate a plugged facility. If the device becomes plugged, it must be replaced. Keeping the areas that drain to infiltration devices well swept and dean will enhance the longevity of these devices. f-or roofs, frequent cleaning of gutters will reduce sediment loads to these devices.