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CRA19930260.PDFCMG jq 3o"24� CITY OF EDMONDS 121 Sth Avenue North, Edmonds WA 98020 Phone: 425.771.0220 • Fax: 425.771.0221 • Web: www.edmondswa.gov DEVELOPMENT SERVICES DEPARTMENT • PLANNING DIVISION q;. 1 a .. Critical Areas Reconnaissance Report Update Critical Areas File Number_ _ CRA199_30260 _ Determination Study Required _ Site Location 9122 Olympic View Drive . ............ . Tax Account Number 27041800203800 r Pro ertOwner N/A' - Applicant N/A Critical Areas Present 0 Geologically Hazardous Areas 2 Erosion Hazard Areas__. THIS PARCEL WAS PREVIOUSLY IDENTIFIED AS A 'CONDITIONAL WAIVER' IN 1993. THE CRITICAL AREAS CODE UPDATE OF 2005 REQUIRES UPDATE OF THE ORIGINAL • DETERMINATION. 0 Site Description During review and inspection of the subject parcel, it was found that the site may contain or be adjacent to critical areas, including Geologically Hazardous Areas (Erosion Hazard Area), pursuant to Chapters 23.40 and 23.80 of the Edmonds Community Development Code (ECDC). Cited sections of the Edmonds Community Development Code (ECDC) can be found on the City of Edmonds website at www.edmondswa.gov. The associated LiDAR map indicates that the subject site slopes gradually downward from southeast to northwest toward Olympic View Drive at a grades between 20% and 25%. A small portion of the slope.east of the existing house has slopes in excess of 40% slopes but that area was created by cutting into the slope to create rockeries during the original development of the house on the site (associated with BLD19940205). Soils throughout the site are identified as Alderwood Gravelly sandy loam (15% - 25% slopes). The slopes in excess of 15% are classified • as potential erosion hazards. Allowed Activities & Exempt Proposals Certain activities are allowed in or near critical area buffers as specified in ECDC 23.40.220. Similarly, certain development proposals may be exempt from Critical Areas requirements (ECDC 23.40.230). If you have any questions about whether your proposed development qualifies as an allowed or exempt activity, please contact a Planner for more information. General Report Requirements Critical Areas Reports identify, classify and delineate any areas on or adjacent to the subject property that may qualify as critical areas. They also assess these areas and identify any potential impacts resulting from your specific development proposal. If a specific development proposal results in an alteration to a critical area the critical areas report will also contain a mitigation plan. You have the option of completing the portion of the study that classifies and delineates the critical areas and waiting until you have a specific development proposal to • complete the study. You may also choose submit the entire study with your specific development application. Please review the minimum report requirements for all types of Critical Areas which are listed in ECDC 23.40.090.D. There are additional report requirements for different types of critical areas (see below). Note that it is important for the report to be prepared by a qualified professional as defined in the ordinance. There are options on how to complete a critical areas study and an approved list of consultants that you may choose from. You may contact the Planning Division for more information. General Mitigation Requirements for all Critical Areas are discussed in ECDC 23.40.110 through 23.40.140. Erosion Hazard Areas Erosion Hazard areas include Alderwood and Everett series soils on slopes of 15 percent or greater, among others. In addition to the general requirements for Critical Areas reports referenced above, specific Critical Area report requirements for Erosion Hazard Areas (which are one of the Geologically Hazardous Areas) are provided in ECDC 23.80.050. Development is regulated within an Erosion Hazard Area and must meet additional criteria. For • erosion hazard areas with suitable slope stability, an erosion and sediment control plan prepared in compliance ECDC 18.30 will be considered to meet the Critical Areas "Study Page 12 Required" determination. The determination of "suitable slope stability" will be made by both • the Planning and Engineering divisions of the City of Edmonds. In areas where the slope stability is not suitable, projects within Erosion Hazard Areas will require a report by a licensed Geotechnical Engineer or other qualified professional. Note that it is important for the report to be prepared by a qualified professional as defined in the ordinance. Report requirements are given in ECDC 23.80.050, and more generally in ECDC 23.40.090.D. Development standards are located in ECDC 23.80.060 and 23.80.070. Determination: Study Required • • This review applies to the entire subject parcel. Depending on the location and project proposed relative to the identified critical areas, certain studies and reports may be required. Please contact the Planning Division at 425.771.0220 if and when you have a specific development proposal for this site in order to discuss the various permits that will be required. Mike Clugston, Associate Planner Name, Title Signature April 14, 2015 Date Page 13 'This map displays LIDAR data at approximate 2-foot contour intervals. This map is for information purposes only and should not r be relied upon for any action. Actual topography should be verified in the field by survey for accuracy. This map is provided with all , — faults on an "as is" and "as available" basis. No warranty of any kind is given. Users of this map agree to indemnify and save harmless the City of Edmonds, its officials, officers, employees s and/or agents from and against any claim, demand or action, irrespective of the nature of the cause of the claim, demand or ; action, arising out of any use or possession of this map." i r /k>' / t i a of E oMo _ Critical Area Map 9122 Olympic View Drive CRA19930260 Update //z/V/S/h 2012Aeria/ Photo NA 1 inch = 100 feet 0 • u :,- TERRA ASSOCIATES, Inc. RC ter Consultants in Geotechnical • Engineering, Geolo and Geology JA 2 1 1994 Environmental Earth Sciences PERM$ • • January. 18, 1994 .Project No. T-2528 Mr. John Daly, c/o Mr. Tony Woods 17607 NE 101 Court . Redmond, Washington 98052: Subject: Geotechnical Report Daly Residence 9122 0137npic View Drive Edmonds, Washington Dear Mr. Daly: As requested; an engineer from Terra Associates, Inc. visited the subject site on.January 6; 1994. The purpose of our visit was to observe the excavation of two test pits in the location of the proposed residence and provide foundation and drainage recommendations. PROJECTDESCRIPTION It is our understanding that the site will be developed bconstruction of a single family residence. The. residence y will require an excavation of approximately 12 feet. in height along the northeast and southeast sidesof the building to facilitate construction of a daylight basement. For building position in relation to the lot boundaries; please refer to the,attached Site Plan, Figure 1:. SITE OBSERVATIONS The site consists of,an undeveloped gently sloping parcel located adjacent to Olympic View Drive. The ground surface slopes downward to the northwest at an inclination of about.4:l (Horizontal:Vertical).. However, a section of the slope near the center of the lot approaches an inclination of 2:1. The lot is bordered, by existing residences to the southeast and southwest, a shallow drainage Swale to the northeast, and Olympic View Drive. to the northwest. A steep slope eight to ten feet high, inclined at about 1:5:1, is located along the west ptoperty.line.. This slope appears to have been created after excavation to level a yard -area. We did not observe any groundwater seepage at the ground surface. Additionally, we did not observe any geomorphic signs of slope instability. 12525 Willows Road, Suite 101, Kirkland, Washington 58034 • Phone (206) 821-7777 Mr. John Daly January 18, 1994 • SUBSURFACE CONDITION Two test pits were excavated on the site using a rubber -tired backhoe. One test pit was excavated near the northeast corner and one near the southwest corner of the proposed building as shown on Figure 1. Our test pits encountered 6 to 12 inches of loose organic silty topsoil. Underlying the topsoil, we encountered loose to medium dense silty sand and fine sand with silt. These soils became dense at four to five feet and continued to 12 feet, the maximum depth explored. We encountered light groundwater seepage at depths of 8 to 9.5 feet. CONCLUSION AND RECOMMENDATIONS Given the conditions described above, it is our opinion that the proposed residence may be developed as planned. The building may be constructed using spread footing foundations placed on the competent native soils or on structural fill placed above competent native soils. Retaining walls ranging from 2 to 12 feet in height may be constructed to attain grades for the daylight basement level. Excavation and Grading • It appears that sufficient room is available to safely make the proposed foundation excavation. However, due to the granular nature of the site soils and groundwater seepage which will likely be encountered during the excavation, we recommend inclining the excavation slopes no steeper than 1:1. Below the groundwater seepage level, sloughing of the excavation side walls could occur. If such conditions develop, flattening of the side slopes to a more stable inclination will be required. Alternatively, buttressing the lower• cut with ecology blocks for a maximum height of four feet could be considered. Native soils excavated on -site, excluding the highly organic topsoil, can be used as structural fill. However, these soil are moisture -sensitive due to their fines (silt and clay size particles) content. Therefore, the use of native soils as structural fill will depend upon their moisture content and the prevailing weather conditions at the time of construction. It will be difficult to achieve proper compaction of these soils when the soil's moisture content is above optimum. If the soils are wet and drying by aeration is not possible, you will need to import suitable wet weather structural fill. This should consist of a clean granular pit -run which has less than five percent fines and a maximum aggregate size of six inches. Structural fill should be placed in horizontal layers and compacted to a density equal to or greater than 95 percent of its maximum dry density, as determined by ASTM Test Designation D-698 (Standard Proctor). 'The fill material should be placed at or near its optimum moisture content. The individual fill layers should not exceed 12 inches in loose thickness. Structural fill beneath buildings should extend beyond the building footprint a distance equal to the fill thickness. All final cut slopes in native soils and structural fill slopes should be constructed with a finish inclination of 2:1 or • flatter. Fills placed on slopes exceeding 4:1 should be keyed and benched into the slope. Fill slopes should be constructed with structural fills as'described in the Site Preparation and Grading section. Project No. T-2528 Page No. 2 Mr. John Daly January 18, 1994 • As soon as possible after construction, permanently exposed slopes should be planted with an appropriate plant mix or provided with physical protection from erosion. FOUNDATIONS The proposed residence may be supported on conventional spread footing foundations bearing on the competent native soils or.on structural fill placed over competent soils. Footings may be proportioned for maximum bearing stresses of 2,500 pounds per square foot (psf), considering both dead and live loads. When wind or seismic loads are included, a one-third increase is permissible. Continuous wall footings should be at least 12 inches wide and isolated column footings at least 18 inches square. Footings exposed to the weather should bear at least 18 inches below adjacent outside final grades. Lateral loads on foundations due to backfill stresses, wind, or seismic loads may be resisted by passive soil stresses on the sides of footings and foundation walls, and by friction on the base of foundations. We recommend estimating passive resistance based on an equivalent fluid weight of 250 pounds per cubic foot (pcf). This value assumes that the footing concrete is poured against neat excavations, or backflled with a structural fill. The calculated friction resistance at the base of foundations should not exceed 40 percent of the'foundation dead load. • LOWER LEVEL WALLS • Lower level walls should be designed to support active earth pressures imposed by an equivalent fluid weighing 35 pcf. Walls restrained from free movement at the top should be designed for an additional uniform pressure of 100 psf. These pressures assume a horizontal backfill which is placed and compacted as a structural fill. Slope surcharges and any other surcharge loads should be added to these pressures if they occur. We will be pleased to provide you with additional information for these conditions, if necessary. Continuous drainage should be provided behind the walls to reduce the potential for hydrostatic pressure buildup behind them. This may consist of placing a perforated pipe covered with gravel and filter fabric material behind the wall. A 12 inch wide zone of free -draining gravel should be placed behind all walls. The final 12 to 18 inches may be capped with native soils to seal the gravel zone. As an option, 'a drainage board material such as Miradrain 6000 may be used to replace the 12 inch free -draining gravel zone. Lower level walls should also be waterproofed prior to backfilling with structural fill. SURFACE AND SUBSURFACE DRAINAGE Surface gradients should be created to direct runoff away from the buildings and slope crests, and should drain toward suitable discharge facilities. No site surface runoff should be allowed to flow unrestricted over the crest of slopes. Project No. T-2528 Page No. 3 Mr. John Daly January 18, 1994 • In addition.to lower level wall drains, we recommend using drains at the .base of all foundation walls. The drains, should empty: into the storm drain system. or to an approved discharge point such as the.street gutter. The footing drains :should be surrounded by at least six inches of pea.gravel or similar drainage rock. Downspouts should be. separately tightlined to discharge. CLOSURE Terra. Associates, Inc. should be provided the opportunity to review the final design and` specifications in order to verify that earthwork and foundation recommendations have been properly interpreted; and. implemented in. the: project design. We :also recommend retaining Terra Associates, Inc: to. provide geotechnical services during construction. The purpose of this is to observe compliance with the design concepts, specifications; and .recommendations. It will also allow for design changes in the event subsurface conditions differ from those anticipated prior to the start of construction. LIMITATIONS This report if the property of Terra Associates, Inc.. and was prepared in accordance with generally accepted • geotechnical engineering practices. This report isintended. for specific, applications to this project, and for the, exclusive use of Mr. John Daly and his authorized representatives. No other warranty, expressed or implied, is made. We. trust this information is sufficient to meet your current needs. Should you have any questions or. require additional information, please call. Sincerely yours, TERRA ASSOCIATES, INC. A ro M�h e Staff Engineer Theodore.J: Sche er, P.E.: f � Principal Engineer o IMS &I g�5------� AM/TJS-ib 1 Encl: Figure I; - Site Plan Figure 2 -Soil Classification System Figure 3 -Test Pit Log Figure 4 - Grain Size Analysis • Project No. T-2528 Page No. 4 • • • 30 feet 295 0 300 / 305 N / 310 /315 i /320 i �325 % Prcfpose esid c / t r / �330 Pam.. 1 TPjQ i /335 ,340 / I isting Hou — 345 i 350 Legend Test Pit Location TP-10 TERRA site Plan Daly Residence ASSOCIATES Edmonds, Washington `-"" Geotechnical Consultants Proj. No.2528 TDate Jan 94 Fiaure 1 • .7 MAJOR DIVISIONS LETTER SYMBOL GRAPH SYMBOL TYPICAL DESCRIPTION GRAVELS Clean GW ' Ci . • �• Well graded gravels, gravel -sand mixtures, little Gravels Q •p • . or no fines. �u aaii More than (less than GP • • • • • • Poorly -graded gravels gravel -sand mixtures little 50% of coarse 5% fines) ; ; ; ; ; ; or no fines. GM ' ' Silty gravels, gravel -sand -silt. mixtures,non- N ai fraction is m > larger than No. Gravels plastic fines. Z o .N E 4 sieve. with fines ; ' Clayey gravels, gravel -sand -clay mixtures, plastic irGC 0 • fines. 0 o ON LO SANDS Clean SW Well -graded sands, gravelly sands, little or H � �z Sands .. no fines. SP 5:- Poorly -graded sands or gravelly sands, little co a More than (less than 5% fines ) 50% of coarse or no fines. 0 V m M o fraction is smaller than SM Silty sands, sand -silt mixtures, non -plastic fines. No. 4 sieve. Sands SC Clayey sands, sand -clay mixtures, plastic fines. with fines t/� N N SILTS AND CLAYS M(• Inorganic silts and very fine sands, rock flour, silty or clayey fine sands or clayey sifts with slight plasticity. CL Inorganic clays of low to medium plasticity, gravelly 0 to Liquid limit is less than 50% clays, sandy clays, silty clays, lean clays. 0 Eo W 9 N o m 0L i i i i i i iiiiiii Organic silts and organic clays of low plasticity. Xr- z° SILTS AND CLAYS MH Inorganic silts, micaceous or diatomaceous fine C9 sandy or silty soils, elastic. W Z 2 Liquid limit is greater than 50% CH Inorganic clays of high plasticity, fat clays. , 0H Organic clays of medium to high plasticity, E organic silts. HIGHLY ORGANIC SOILS PT Peat and other highly organic soils. DEFINITION OF TERMS AND SYMBOLS W Standard Penetration Density Resistance in Blows/Foot T 2. OUTSIDE DIAMETER SPLIT I SPOON SAMPLER Very loose. 04 2.4" INSIDE DIAMETER RING SAMPLER Loose 4-10 OR SHELBY TUBE SAMPLER ° Medium dense 10.30 P SAMPLER PUSHED Dense 30-50 * SAMPLE NOT RECOVERED H Very dense >50 Q WATER LEVEL (DATE) 0 WATER OBSERVATION STANDPIPE Standard Penetration C TORVANE READINGS, tsf g Density Resistance in Blows/Foot qu PENETROMETER READING, tsf Ca Very soft 0 2 W MOISTURE, percent of dry weight c Soft 2-4 pcf DRY DENSITY, pounds per cubic foot J Medium stiff 4-8 LL LIQUID LIMIT, percent stiff 8-16 . Very stiff - 16.32 PI PLASTIC INDEX Hard >32 N STANDARD PENETRATION, blows per foot TERRA SOIL CLASSIFICATION SYSTEM Daly Residence ASSOCIATES Edmonds, Washington Geotechnical Consultants Proj. No. T-2528 I Date 1/94 Figure 2 Test Pit No. TP-1 Logged by: AM Approximate Elev. 322 Date: 1-7-94 Depth (ft.) - UCS/ Soil Description W 0 GSrap.hHit N nro:;nir qi1t tnn-qn FI—d--Mp. old drainlnnqp- tiles plugged with silt. Tan -gray SAND with silt, trace gravel, damp to moist, loose P to medium dense. 11.4 Dense at 4 feet. 5 — .*.,.,: I 10 Logged by: AM Date: 1-7-94 Depth (ft.) USCS/ 0 Graph 0 10 1E L�-YF; �---Y —IIMIK� FWVIIY SICtUOU 11110 IVVILJ VVILII III 'c Lu 13.6 me dium ravel, occasional 6 Inch cobbles, moist, very dense. Tan -gray poorly fine SAND with silt, moist, dense. 14.9 Test pit terminated at 12 feet. Moderate seepage encountered at 9.5 feet. Test Pit No. TP-2 Approximate Elev. 308 Soil Description W Black organic silt topsoil. 18.3 Reddish brown silty SAND, damp, loose to medium dense. silty SAND with fine gravel, damp, medium dense. Gray s 8.8 SM Dense at 5 feet. Gray slightly mottled poorlygraded fine SAND with silt, wet, SP dense. M X-1 17.9 S Gray partially cemented, poorly graded fine sand with silt, M damp, dense. 19.2 Test pit terminated at 10 feet. Moderate seepage encountered at 8 feet. TEST PIT LOGS TERRA Daly Residence ASSOCIATES Edmonds, Washington Geotechnical Consultants Proj. No. T-2528 I Date 1/94 Figure 3 Proj. No. 2528 - CA FILE NO. q 3 —U D Critical Areas Checklist Site Information (soils/topography/h drolo/gyv/vegettaation) 1. Site Address/Location:���-- cal ew �'✓/c 2. Property Tax Account Number: I86?7 0 3FO& 0 7 3. Approximate Site Size (acres or square feet): S 4. Is this site currently developed? yes; /A no. If yes; how is site developed? 5. Describe the general site topography. Check all that apply. Flat: less than 5-feet elevation change over entire site. 4/Rolling: slopes on site generally less than 15% (a vertical rise of 10-feet over a horizontal distance of 66-feet). Hilly: slopes present on site of more than 15% and less than 30% ( a vertical rise of 10-feet over a horizontal distance of 33 to 66-feet). Steep: grades of greater than 30% present on site (a vertical rise of 10-feet over a horizontal distance of less than 33-feet). Other (please describe): 6. Site contains areas of year-round standing water: 116) ' ; Approx. Depth: 7. Site contains areas of seasonal standing water. Approx. Depth: • What season(s) of the year? 8. Site is in the tloodway Ito floodplain de") of a water course. 9. Site contains a,cyeek or an area where water flows across the grounds surface? Flows are year- round? A(,0 Flows are seasonal? (What time of year? ). •10. Site is primarily: forested ; meadow _;shrubs ; mixed ; - urban landscaped (lawn,shrubs etc) A'_ . 11. Obvious wetland is present on site: ------------------------------------------ --------- --For.City::StaffUse Onlv------ ------- ------------------------------ 1. Site is Zoned? 2 SCS mapped soil type(s)? AL=U,1Q= G,Y&rw V 5AgDtl LoAren 3. Wetland inventory or C.A. map indicates wetland present on site? 4 Critical. Areas` inventory or C.A. map indicates Critical'Area onsite? L 7;95 5 : Site within designated earth' subsidence landslide hazard area? C� 6. Site designated on the Environmentally Sensitive Areas Map? �Q IDETERNIINATION STUDY REQUIRED CONDITIONAL WAIVER • WAIVER Reviewed by: Planner Dat Rev 09/29/93 City of Edmonds Critical Areas Checklist The Critical Areas Checklist contained on this form is to be filled out by any person preparing a Development Permit Application for the City of Edmonds prior to his/her submittal of a development permit to the City. The purpose of the Checklist is to enable City staff to determine whether any potential Critical Areas are or may be present on the subject property. The information needed to complete the Checklist should be easily available from observations of the site or data available at City Hall (Critical Areas inventories, maps, or soil surveys). An applicant, or his/her representative, must fill out the checklist, sign and date it, and submit it to the City. The City will review the checklist, make a precursory site visit, and make a determination of the subsequent steps necessary to complete a development permit application. With a signed copy of this form, the applicant should also submit a vicinity map or plot plan for individual lots of the parcel with enough detail that City staff can find and identify the subject parcel(s). In addition, the applicant shall include other pertinent information (e.g. site plan, topography map, etc.) or studies in conjunction with this Checklist to assist staff in completing their preliminary assessment of the site. I have completed the attached Critical Area Checklist and attest that the answers provided are factual, to the best of my knowledge (fill out the appropriate column below). Owner / Applicant: �Je ( (er �0-61r Name Street Address City, State, ZIP Phone z C� la zl ti3 i , a re Date Applicant Representative: ��� iJ'l� J�s�ir✓C Name ,303 S-'RArS Street Address City, State, IP Phone Signature Date �J I• • L� City of Edmonds Critical Areas Determination Applicant: Jeffery Cable Determination #: CA-93-260 Project Name: Permit Number: Site Location: 9122)Olympic View Drive Property Tax Acct #: 18270420380007 Project Description: Single Family Residence Waiver Criteria (all criteria must be found to apply): XXX There will be no alteration of the Critical Area or its required buffers; XXX The development proposal will not impact the Critical Area in a manner contrary to the goals, purposes, objectives and requirements of the Critical Areas ordinance; XXX The development proposal meets the minimum standards of the Critical Areas ordinance; XXX The above findings are based on the following conditions of approval: 1. Before any permit application may be applied for, submit to the Planning Department a topographic survey prepared by a Licensed Land Surveyor delineating Steep Slope Hazard Areas. Any slope over 30% with more than 10 feet of rise will be classified as a Steep Slope Hazard Area. A 50 foot buffer is required from both the top and toe of the slope. A 15 foot building setback is required from the 50 foot buffer. 2. If the results of the above survey determine the lot unbuildable, any development which is not identified as an exception per ECDC Chapter 20.15B must receive a Reasonable Use Exception or a Variance pursuant to ECDC 20.15B.180A and 20.15B.040C). 3. All proposed development of the subject lot must meet the requirements of Chapter 19.05 of the Edmonds Community Development. Code. fCrJ��ul�t_IS �J Z� 3 Name Signature Da ��• -- ALL REQUIREMENTS AND"NDITIONS OF THIS SUBDIVISION MU-'" r"BE COMPLETED PRIOR TO ISSUANCE•T0°>.)UILDING PERMITS. I EXHIBIT 2 N. K 114 SEC, 18, TI✓N. 27 N., R. 4 E., I✓. M. 30 / Q� sue• .. . / M ,A'� i i \ SCALE !' 50' z _ � 4' s ee'1e•20 LOT • M � /aoo�sr 16JI31/SF • I /1/ f G / Z S/4/�/7D.lyd ..C�M'aYYTo ,��I�/• /��/ nv •�,.— CDT 2 `�, '• �n NOUSE / y ti ►. ' ~ ° 14 r N 5B�B9 � •� 6L - L��• r,4Ytc,c ' � 24.5. 4.271 , ,Sit,si•q. a b ' FOR �e�► .cr ;�`' t)EFFERY CABLE . � tit �" • � •F �� . a• • E�If1l�;���t>t MD S PL, 8.14473 EVERGREEN THEE EVEFlGRE�N T EE i0 9 AUTHORIZED frt3A RECORDING oww000 THE CITY OF EDMONDS BY - DATE 3-za- 90 WAGON LAND SURVE G $IJEE / OF iM '1010110 3,A Von•,2384PAGE2926 P. W. DEPT. ENGINEERING DIV. EXAMINED BY—f=-=--- DATL