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1236 7TH AVE S.PDF11111111IIII lill6960 1236 7TH AVE S ADDRESS: IA5g� TAX ACCOUNT/PARCEL NUMBER: ���� 1Z& BUILDING PERMIT (NEW STRUCTURE)CA:� —/(JU COVENANTS(RECORDED)FOR: CRITICAL AREAS: `�/ /� e�� DETERMINATION: ❑ Conditional Waiver 2igltudy Required ❑ Waiver DISCRETIONARY PERMIT DRAINAGE PLAN DATED: PARKING AGREEMENTS DATED EASEMENT(S) RECORDED PERMITS (OTHER): PLANNING DATA CHECKLIST DA SCALED PLOT PLAN DATED: SEWER LID FEE $: LID #: SHORT PLAT FILE: LOT: BLOCK: SIDE SEWER AS BUILT DATED: " / g SIDE SEWER PERMIT(S) #: 3 ,� SOILS REPORT DA' STREET USE / ENCROACHMENT PERMIT #: WATER METER TAP CARD DATED: OTHER: L:\TEMP\DST's\Forms\Street File Checklist.doc DA"Zon IM ;y 653 673 1138 Ila, 1137 1130 1141 1138 1140 7131 1137 130 126 Q 03 1131 1126 1132 1157 ,134 1132 ._ 1131 .. . 901 , /� 1140 Q 600 /142 1140 1143 1161 1142 1141 1134 1160 1s0 1161 1 ELM WAY 1148 y 1161 ,lae y 138 C AVE 1143 B00 660 HIghI6rMPeAc n g W 0{ I119 1169 Q 631 839 1168 Park 152 „63 1768 1149 14 � •«e..a...am.««., ,ew,,,mo,,,....,.,,,,�,..«.w.. no 1157 Iles 1147 1160 14 612 6" 700 70B m g+ $ 780 1201 B,B no 841 ■ ii �0 0 2 701 709 716 La,� i• �• 1208 1211 823 835 22004 62362 W 9 6? 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(Yes / No / DNA) IG ❑ DE CHED ST CTURES: ❑ ROCK 1 0 ❑ FENC /T LLISES: vv ❑ BA WINDOWS ROJECTING MODULATION: AIRS 1 �..�iS -- of �l'0 dac. M cd ief 1 #7 IS PARKING: Required:Actual: LOT AREA: LS q) (P LOT COVE _ / /�� A�� ! G 3 Calculations: Mak 5 o f GN BUILDING HEIGHT: --��-1 Datum Point: ��S I K -oi,4 a I Datum Elevation: p' a Maximum Allowed: Actual Height: A:D.U. CREATED?: No / Yes) SUBDIVISION: --s�--0L4 Lf LEGAL NONCONFORMING LAND USE DETERMINATION ISSUED: Yes o) OTHER: Plan Review By: NewBPPlanningDataForm:DOC - `nC. I sa" Ci}�� of EdmondsPERMIT NO: 9837 SIDE SEWER PERMIT PERMIT EXPIRES_ Address of Construction: % 23 (0, — 7 714 4 V6. $ LID # Property Tax Account Parcel No. e2703 P✓M 030-/1 Attach copies of all access and utility easements Verified and Approved by Owner and/or Contractor: Contractor License #: Single Family ❑ Multi -Family (No. of Units ;z ❑ Commercial (No. of Units ) ❑ Public ilding Permit #: 20...3- /007 Invasion into City *Right -of Way:.❑ Yes . No *RW Construction Permit # Cross, other **Private Property: ❑ Yes. No **Attach legal description and copy of recorded easement. Ow r or c6htractor signature and acknowledgement statement: Bf signing for this permit I certify that I have read the City's public handout entitled Side Sewer Specifications, and shall comply with all City requirements outlined therein Date W CALL DIAL -A -DIG (1-800-4`-5555) 'BEFORE ANY EXCAVATION' W. W FOR INSPECTION CALL 425-771-0220 extensiori40 W 24 HOUR NOTICE REQUIRED FOR ALL INSPECTION REQUESTS FOR OFFICE USE ONLY Permit F�eee $ Repair Fee $ Issued B " $ �� Date lssu iV arge Assessment Fee $ Receipt No: oL City Permit Surcharge Fee $E00 Total Fees Paid $ NOTE: IF JOB SITE IS NOT READY FOR INSPECTION WHEN INSPECTOR ARRIVES A $45 RE -INSPECTION FEE WILL BE CHARGED. Job Site Ready YES NO- Date: Initial: Partial Inspection: Date: Initial: Partial Inspection: Date: Initial: FINAL INSPECTION APPROVED: Date: t� PERMIT MUST BE POSTED ON JOB SITE t� White Copy: File .Green Copy: Inspector Buff Copy: Applicant to Street File: ❑ L;temp,bldg;forms;sspermitj Ig4/00 1226 C 1232 SIDE INS" 1236 ERNC[ WILDERNESS BLUFF .RK SEWER STUB FOR LATERAL �LLED W/SH❑RT PLAT ilM- of ED*CITY OF EDMONDS SIDE SEWER AS -BUILT ADDRESS U' 1236 - 7th Avenue South HOMEOWNER CONTRACTOR SCALE Jerry Davis MT, Shadow Const, Inc, NTS DATE PERMIT 4-19-2004 BY K, Haney NO. 9837 fewv- 5 -03- 34 rev'$ok GAAf aF 1 � p •I ,cl 9 -7 N �n ��r��icn rno P•_a AKIRI �v ,.w NJE AC TASTERIA'L. 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U '�'� L�GC1L = 1 88 S.F. 6c77 Gl SGALE; 1��=fit v = io S L S • F. -1—UT&,L- — �ZDOS:F, FILL.: �� C � pISPOSE OF '=XGESS AT PPPR•avE� s tTG za STREETFILE SSh.Pr=DGvG�til 44 %z.5 n W cc 5 a W cr- U f- z w FIfLt= 1 1-1YDrz.. rQ% S�0 ��;R��0YEED ►-_ � 2c��03 PERMIT COUNTER 4 • • ZONE SETBACM. �Fft01� � SIDE REAR OTHER 2 HEIGHT 240 - Z304 k rota i g0.�a�R. slab ek 1� J 2- 0 carr .,... • 43 slab ex. I,.,e Z3(.S Z3ti y4 o yflH A', 7 Gyp G&A� LY EXPIRES Cam+ (A,& 7.(07(p5)= 37 GY F 41 ( (4a4. Gor�p, ��-br 1 s9�� = SI CI�tS� = sq C-y STREET FILE � c� owEQ) 2414 2� D3 v PERMIT COUNTER E • _4 T, C'►E TECH ' CONS LTANTS, INC. j t Ala i Jackson 1654 01 Highway 99 Ly IInwood, Washington 99037 Supject: Geotechnical Engineering Study Prop sed Wilderness Bluff Short Plat 123,E 7th Avenue South Edmonds, Washington Oesiar Mr. Jackson: 13256 N"eut 2(kh Sued, Suite 16 Bellovue, Wiuhington 98pp.5 (425) 747-5618 FAX (a25) 747-8561 September 3, 2003 via facsimile: (425) 767-9112 JN 03322 We� are pleased to present this geotec hnicat engineering report for the proposed single-family res'dences to be constructed in Edmonds, Washington. The scope of our work consisted of exploring site surface and subsurface conditions, and then developing this report to provide recce )mmendadons for general earthwork and design criteria for foundations and retaining wails. Thi D work was authorized by your acceptance of our Contract for Professional Services dated July 24, 2003. W were provided with a preliminary site plan that includes some topographic information. AFM Ind stries, Inc. developed this plan, which is dated September 14, 2002. Based on this plan and on onversations with Alan Jackson, we anticipate that the development will consist of dividing the ap roximately 1.8-acre site into four lots and constructing one single-family residence on each lot. Th houses will be accessed via driveways off of 7th Avenue South and will be set back 25 feet fro the street. Each house will. consist, of one ,floor of living space and a garage over a daylight ba ement- Some cuts and fills will'be necessary to achieve the proposed finish floor elevation of ap ,'in 8 to 10 feet below existing street grade, and a small backyard will be filled at finish fl r elevation. No development is proposed on the western side of the site, as this area is a de ignated wetland. If t e scope of the project changes from what we have described above, we should be provided wit revised plans in order to determine if modifications to the recommendations and conclusions of thi report are warranted. SITE CONDITIONS SURFACE Th I Vicinity Map, Plate 1, illustrates the general location of the site. The undeveloped, wooded site is I sated on the western side of 7th Avenue South in Edmonds. The site slopes from east to west, wit elevations varying from approximately 246 feet at the southeastern comer to .approximately 20 feet at the southwestern comer. Most of the western part of the site is a relatively flat destignated wetland, and there is a creek that winds along the western property line. The proposed de elopment area is located on the sloped, eastern portion of the site. The slopes are Inclined at ap roximately 30 percent and are covered with tall deciduous and evergreen trees. The ground is I GEOTECH CONSULTANTS, INC. OCT 17 2603 DEVE CITY OF EM.jo"'CES C?R. DS STREET FILE Jackson JN 03322 amber 3, 2003 Page 2 fired with blackberry and morning glory vines near the street and with ferns and other low Rh vegetation elsewhere. There is an area on the southem part of the site where ,oximately 10 feet of yard waste and construction debris have been dumped to form a locally. per slope. Dumped garbage, yard waste, and construction debris were observed scattered ighout the site. The adjoining properties are developed with single-family residences. CE subsurface conditions were explored by excavating seven test pits at the approximate ons shown on the Site Exploration Plan, Plate 2. Our exploration program was based on the )sed construction, anticipated subsurface conditions and those encountered during ration, and the scope of work outlined In our proposal. Thf test pits were excavated on July 24, 2003 with a small, rubber -tracked trackhoe provided and ope rated by Alan Jackson. A geotechnical engineer from - our staff observed the excavation pro :ess, logged the test pits, and obtained representative samples of the soil encountered. "Grab" san iples of selected subsurface soil were collected from the backhoe bucket. The Test Pit Logs are provided in Plates 3 and 4 of this report. e test pits encountered a 6- to 24-inch layer of topsoil and 2 to 3 feet of weathered sand d gravel with abundant roots overlying dense to very dense sand and gravel with cobbles d occasional boulders. One to 2 feet of sand and gravel fill was encountered overlying 3 topsoil In Test Pits 1, 4, and 7. The dense to very dense sand and gravel was countered to the maximum explored depth of 9 feet below existing grade. Tbe.depths of it layers, including topsoil, that are indicated on the logs are approximate. More exact finition of soil unit thicknesses would require more explorations. rge amounts of yard waste, garbage, and construction debris were observed scattered ,oughout the site and were encountered in the topsoil and in the fill. This debris will need be removed during site clearing. Groundwater seepage was observed at depths of 6 to 6.5 feet in Test Pits 3 and b; however, the test pits were left open for only a short time period. Therefore, the seepage levels on the logs represent the location of transient water seepage and may not indicate the static groundwater level. It should be noted that groundwater levels vary seasonally with rainfall and other factors. Th final logs represent our interpretations of the field logs. The stratification lines on the logs reresent the approximate boundaries between soil types at the exploration Iocatlons. The actual tra isdion between soil types may be gradual, and subsurface conditions can vary between exI iloration locations. The logs provide specific subsurface information only at the locations tested. Th relative densities and moisture descriptions indicated on the test pit logs are interpretive de cr otions based on the conditions observed during excavation. Th compaction of backfill was not in the scope of our services. Loose soil will therefore be found In he area of the test pits. if this presents a problem, the• backfill will need to be removed and rer laced with structural fill during construction. GEOTECH CONSULTANTS, INC. rriac uy Jackson JN 03322 amber 3, 2003 Page 3 CONCLUSIONS AND RECOMMENDATIONS SECTION CONTAINS A SUMMARY OP OUR STUDY AND FINDINGS FOR THE PURPOSES OF A RAL OVERVIEW ONLY. MORE SPECIFIC RECOMMENDATIONS AND CONCLUSIONS ARE AINED /N THE REMAINDER OF THIS REPORT. ANY PARTY RELYING ON THIS REPORT SHOULD THE ENTIRE DOCUMENT. proposed development will consist of dividing the site into four roughly equal lots and eructing one single-family residence on each lot. The recommendations presented in this rt are based on the assumption that the earthwork for all of the houses can be completed at If the development plans change, we should be notified so that we may update our ,emendations accordingly. Thla test pits conducted for this study encountered loose fill, topsoil, and highly weathered sand and gr ivel overlying dense to very dense sand and gravel. Competent, native soils were encountered be ween 1 and 4 feet below existing grade, with the thicker loose, surficial layer encountered near thi top of the slope on the eastern side of the site. The native sand and gravel soils encountered be ow the root line are competent to support the four proposed single-family residences on co ventlonal foundations. These soils are also suitable for reuse as structural fill throughout the sit . The topsoil and weathered sand may be reused as fill In non-structural areas such as la scaping beds, Dumped construction debris, yard waste, and garbage were observed th ughout the site. This material is not suitable for reuse as fill and should be removed during site .►__ ed on the topographic Information provided to us, and on our understanding of the project. so ne cuts and fills will be required to achieve the proposed finish floor elevation of 8 to 10 feet be ow existing street grade. Because the proposed houses will be set back at least 25 feet from thf edge of the street, cut slopes inclined no steeper than 1:1 (Horizontal: Vertical) can be made will in the eastern property line. Please note that this inclination applies only to the native sand and gr vel; the fill and debris encountered near the surface on most of the site should be removed du ing site clearing. Also, groundwater was encountered in two of the downslope test pits during ex 31oration. If groundwater is encountered during the excavation on the upslope side of the site,' the cut slopes below the groundwater table will likely experience some sloughing or caving. To mi igate the potential for instability of the cut slopes below the groundwater table, the cuts may ha re to be backfilled with rock ballast. We should be contacted at once if groundwater is en entered during the excavation of the cut slopes. All cut slopes should be protected Im ediately with plastic sheeting and should be monitored dally by the superintendent for i ications of instability. Soil stockpiles and debris from site clearing should not be stored at the to of any cut slope. T foundation walls between the adjacent residences are approximately 10 feet apart as shown o the site plan. The soil between the foundation walls of the proposed residences should be re oved as part of the mass excavation where it cannot be inclined at 1:1 (HY). Taking into a ount a space allowance of 2 feet on each side for footings, drains, and forms, cuts cannot ex ed 3 feet between the foundation walls. OEOTECH CONSULTANTS, INC. '_ . ".•• • rHtac u� Jackson • !mber 3, 2003 JN 03322 Page 4 ea ed on the site plan, it appears as though cuts on the order of 6 to 8 feet will be necessary to ach eve finish floor elevations of the northernmost houses and southemmost. The plan shows each of these houses set back 5 feet from the northern and southern property lines, respectively. Be ause the site soils may be inclined no steeper than 1:1 (H:V) shoring will be required to make the proposed cuts unless the finished floor elevations of these structures are revised. We can make recommendations for the design of these temporary shoring walls if they are required. Bai ad on the topographic information provided to us, fill on the order of 6 to 8 feet will be required to evel the finish floor of each house at its proposed finish floor elevation. However, we reo immend that footings be placed on no more than 5 feet of structural fill. Finished fill slopes sho Ad not be inclined steeper than 2.5:1 (H:V). Depending on the desired back yard layout and the location of the wetland buffer, it may prove more economical to overexcavate, place the d nslope foundations on native, dense sand and gravel and leave a tall crawl space, or to step the buildings down the slope. Altematively, a reinforced fill rockery could be constructed near the we tern edge of the development area to level the site. Regardless of which method is chosen, we rec mmend that the downslope foundation wall be designed as a retaining wall to retain the soil wit in the crawl space or beneath the slab down to the footing level. Fill rockeries taller than 4 feet will require geogrid reinforcement; 'we can provide a design If necessary. We should review the grading plans once the house layouts are finalized. The site sand and gravel below the root line is suitable for reuse as structural fill. The earthwork con tractor should prepare the flit areas by removing the topsoil and highly weathered sand above the root line. The new fill should be benched Into the dense native soils by cutting flat benches into the dense native sous. Each horizontal lift of fill should be tested to ensure that adequate cory paction is being achieved. foundation walls should be backfilled with free -draining structural fill. The site sand and gravel Af the root line Is acceptable for use as wall backfill. Footing drains should be installed at the i of each foundation wall.. We recommend that each residence have its own independent elation drainage system, so two separate drains would need to be placed in the backfill een the adjacent houses. Drainage should also be provided behind all retaining walls and Th erosion control measures needed during site development will depend heavily on the weather con Itions that are encountered during construction. Site clearing will expose a large area of bare soil and the erosion potential on the site Is moderate due to the slope of the site. We anticipate tha a silt fence will be needed around the downslope sides of any cleared areas and around the we ands. Strew bales should be placed against the silt fence for added protection during grading. R ed construction access roads should be extended into the site to reduce the amount of mud Carl led off the property by trucks and equipment. Wherever possible, these roads should follow the alig iment of planned pavement4. Soil stockpiles should be covered with plastic during wet we4Mer. Following rough grading, it may be necessary to mulch or hydroseed bare areas that will not pe immediately covered with landscaping or an impervious surface. Consultants, Inc. should be allowed to review the final development plans to verify that the nendations presented in this report are adequately addressed in the design. Such a plan would be additional work beyond the current scope of work for this study, and it may include is to our recommendations to accommodate site, development, and geotechnical lints that become more evident during the review process. QEOTECH CONSULTANTS. INC. 1MVL VO • Jackson rJN 03322 amber 3, 2003 Page 5 recommend including this report, in its entirety, In the project contract documents. This report ild also be provided to any future propertyowners so they will be aware of our findings and mmendations. CONSIDERATIONS Thq site is located within Seismic Zone 3, as illustrated on Figure No. 16-2 of the 1997 Uniform Building Code (USC)., In accordance with Table 16-J of the 1997 UBC, the site soil profile within 10 feet of the ground surface is best represented by Soil Profile Type Sc (Very Dense Soil). The sit soils are not susceptible to seismic liquefaction because of their dense nature. FOUNDATIONS Th proposed residences can be supported on conventional continuous and spread footings be ring on undisturbed, dense, native sand and gravel, or on up to 5 feet of properly compacted st aural fill placed above this competent native soil. See the section entitled General Earthwork an Structural Rif for recommendations regarding the placement and compaction of structural fill be eath structures. Adequate compaction of structural fill should be verified with frequent density tes ng during fill placement. Prior to placing structural fill beneath foundations, the excavation sh d be observed by the geotechnical engineer to document that adequate bearing soils have be n exposed. We recommend that continuous and individual spread footings have minimum wi ohs of 16 and 18 inches, respectively. Footings should also be bottomed at least 18 inches bel the lowest adjacent finish ground surface. The local building codes should be reviewed to det line If different tooting widths, or embedment depths are required. Footing subgrades must be cleaned of loose or disturbed soil prior to pouring concrete. Depending upon site and eq ipment constraints, this may require removing the disturbed soil by hand. An allowable bearing pressure of 2,000 pounds per square foot (psf) is appropriate for footings supported on the dense, native sand and gravel found below the root line or on structural fill placed a e these competent native soils. A e-third Increase In this design bearing pressures may be used when considering short-term wi or seismic loads. For the above design criteria, it is anticipated that the total post -construction se ement of footings founded on competent, native soil, or on structural fill up to 5 feet in thi ness, will be about one-half inch, with differential settlements on the order of one-half Inch In a dis nce of 50 feet along a continuous footing with a uniform load. Lat iral loads due to wind or seismic forces may be resisted by friction between the foundation and the bearing soil, or by passive earth pressure acting on the vertical, embedded portions of the fou idatlon. For the latter condition, the foundation must be either poured directly against relatively level, undisturbed soil or be surrounded by level structural fill. We recommend using the following ultl ate values for the foundation's resistance to lateral loading, OEOTECN CONSULTANTS, INC. . - V! Jackson 0 amber 3, 2003 • JN 03322 Page 6 PARAMETER VALUE Coefficient of Fdctlon 0,40 Passive Earth Pressure 250 pcf Whore: (1) pcf is pounds per cupio foot, and (ill passive earth pressure is computed using the equivalent fluld density. If tfie ground in front of a foundation is loose or sloping, the passive earth pressure given above will no be appropriate and we should be contacted for a revised recommendation. We recommend maintaining a safety factor of at least 1.5 for the foundation's resistance to lateral loading, when usl g the above ultimate values. FOUNDATION AND RETAINING WALLS Ining walls backfilled on only one side should be designed to resist the lateral earth pressures sed by the soil they retain. The following recommended parameters are for walls that restrain backfill: PARAMETER Active Earth Pressure " VALUE 30 pcf Passive Earth Pressure 300 pof Coefficient of Friction 0,40 Soil Unit Weight 135 pcf Where: (1) pet Is pounds per cubic That and (11) active " passivA 02rth pressures are computed using the equivalent fluid pressures. • For a restrained wall that cannot deflect at least 0.M times he height, a uniform MMI prpssuro equal to 10 psf times the height of the wall should be added to the above active equivalent fluid pressure. values given above are to be used to design permanent foundation and retaining walls only. passive pressure given is appropriate for the depth of level structural fill placed in front of a ining or foundation wall only. The values for friction and passive resistance are ultimate values do not Include a safety factor. We recommend a safety factor of at least 1.5 for overturning sliding, when using the above values to design the walls. Restrained wall soil parameters ild be utilized for a distance of 1.5 times the wall height from corners or bends in the walls, is intended to reduce the amount of cracking that can occur where a wall, is restrained by a sr design values given above do not include the effects of any hydrostatic pressures behind the ; and assume that no Surcharges, such as those caused by slopes, vehicles, or adjacent latlons will be exerted on the walls. If these conditions exist, those pressures should be added GGOTECH CONSULTANTS. INC. I MVL Vo Jackson • • JN 03322 ember 3, 2003 Page 7 to t e above lateral soil pressures. Where sloping backfill Is desired behind the walls, we will need to given the wall dimensions and the slope of the backfill in order to provide the appropriate des n earth pressures. The surcharge due to traffic loads behind a wall can typically be acc unted for by adding a uniform pressure equal to 2 feet multiplied by the above active fluid del e dry; a traffic surcharge should be applied to the eastern foundation wall of each residence. He construction equipment should not be operated behind retaining and foundation walls within a di tance equal to the height of a wall, unless the walls are designed for the additional lateral pre ures resulting from the equipment The wall design criteria assume that the backfill will be welt compacted in lifts no thicker than 12 inches. The compaction of backfill near the walls should be ccomplished with hand -operated equipment to prevent the walls from being overloaded by the hig er soil forces that occur during compaction. Backfill placed behind retaining or foundation walls should be coarse, free -draining structural fill containing no organics. This backfill should contain no more than 5 percent silt clay particles and have no gravel greater than 4 inches in diameter. The percentage of rticles passing the No. 4 sieve should be between 25 and 70 percent. The native sand nd' gravel encountered below the root line during our explorations is suitable for reuse as staining wall backfill. ie purpose of these backfill requirements is to ensure 'that the design criteria for a taining wall are not exceeded because of a build-up of hydrostatic pressure behind the all. The top 12 to 18 inches of the backfill should consist of a compacted, relatively ,permeable soil or topsoil, or the surface should be paved. The ground surface must also )pe away from backfilled walls to reduce the potential for surface water to percolate into a backfill. The section entitled General Earthwork and Structural Fill contains commendations regarding the placement and compaction of structural fill behind retaining id foundation walls. ie above recommendations are not intended to waterproof the below -grade walls. The !rformance of subsurface drainage systems will degrade over time. Therefore, derproofing should be provided where moist conditions or some seepage through the Ills are not acceptable in the future. This typically Includes limiting cold -joints and wall netrations, and using bentonite panels or membranes on the outside of the walls. ,plying a thin coat of asphalt emulsion is not considered waterproofing, but will only help prevent moisture, generated from water vapor or capillary action, from seeping through concrete. With any project, adequate ventilation of basement and crawl space areas is portant to prevent a build up of water vapor that may be transmitted through concrete ills from the surrounding soil. Th building floors may be constructed as slabs -on -grade atop the native sand and gravel, or on st ural fill. The subgrade soil must be in a firm, non -yielding condition at the time of slab con truction or underslab fill placement. Any soft areas encountered should be excavated and repl�ced with select, imported structural fill. GEOTECH CONSULTANTS. INC. Jackson JN 03322 ember 3, 2003 Page a All labs -on -grade should be underlain by a capillary break or drainage layer consisting of a minimum flinch thickness of coarse, free -draining structural fill with a gradation similar to that dis ussed in Permanent Foundation and Retaining Walls. As noted by the American Concrete =11ture ute (ACI) in Section 3.2.3 of the Guides for Concrete Floor and Slab Structures. proper protection is desirable immediately below any on -grade slab that will be covered by tile, woc d, carpet, impermeable floor coverings, or any moisture-sensltive equipment or products. ACI alac notes that vapor retarders, such as 6-mil visqueen, are typically used. A vapor retarder is deft ied as a material with a permeance of less than 0.3 US perms per square foot (psf) per hour, as determined by ASTM E 96. It is possible that concrete admixtures may meet this specification, althpQugh the manufacturers of the admixtures should be consulted. However, if no potential for vapor passage through the slab is desired, a vapor barrier should be used. A Vapor barrier, as defined by ACI, is a product with a water transmission rate of 0.00 perms per square foot per hour :tt tested In accordance with ASTM E 96. Reinforced membranes having sealed overlaps can this requirement. . In t ie recent past, ACI (Section 4.1.5) recommended that a minimum of 4 inches of well -graded con pactable granular material, such as a 5/8 inch minus crushed rock pavement base, should be plac ed over the vapor retarder or barrier for protection of the retarder or barrier and as a "blotter" to aid in the curing of the concrete slab. Sand was not recommended by ACI for this purpose. Hov fever, the use of material over the vapor retarder Is controversial as noted In current ACI literpture because of the potential that the protection/blotter material can become wet between the tim of its placement and the installation of the slab. If the material is wet prior to slab placement, whih Is always possible in the Puget Sound area, it could cause vapor transmission to occur up thr ugh the slab in the future, essentially destroying the purpose of the vapor barriertretarder. Th refore, if there is a potential that the protection/blotter material will become wet. before the slab is i stalled, ACI now recommends that no protectioivblotter material be used. However, ACI then mmends that, because there Is a potential for slab cure due to the loss of the blotter material, join spacing in the slab be reduced, a low shrinkage concrete mixture be used, and 'other me ures" (steel reinforcing, etc.) be used. ASTM E-1643-98 "Standard Practice for Installation of W�er Vapor Retarders Used in Contact with Earth or Granular Fill Under Concrete Slabs" ge erally agrees with the recent ACI literature. W recommend that the contractor, the project materials engineer, and the owner discuss these iss es and review recent ACI literature and ASTM E-1e43 for installation guidelines and guidance on he use of the protectlorVblotter material. Our opinion is that with Impervious surfaces that all me ns should be undertaken to reduce water vapor transmission. anticipate that rockeries may be used to level the backyards. At least 12 inches of quarry Is should be placed behind rockeries to reduce the potential for soil eroding through them. A )rated drain pipe surrounded by drain rock should be installed behind the rockeries. recommend limiting fill rockeries to a height of 4 feet and constructing them on only competent re soil. The lower two-thirds of the rockery should be constructed with 3- to 4-man rocks and fill should be placed and compacted to structural fill requirements. Prior to rockery ,truction, the fill should be placed beyond the planned rockery location and then cut nearly cal so that the soil in back of the rockery is thoroughly compacted. Since grading plans were established at the time of this report, the relationship between the proposed footings and GEOTECH CONSULTANTS, INC. ---•--t rMVC A Jackson • JN 03322 :mbar 3, 2003 Page 9 iosed rockeries could not be determined. Foundations closer to the back of the rockery than times the height of the rockery would exert a surcharge on the adjacent rockeries; surcharged eries or rockeries taller than 4 feet will require the use of geogrid reinforcement in the backfill, can provide a rockery detail if necessary. Th construction of rockeries Is, to a large extent, an art not entirely controllable by engineering me ods and standards. It is imperative that rockeries, if used, are constructed with care and in a pro r manner by an experienced contractor with proven ability in rockery construction. The roc eries should be constructed with hard, sound, durable rock in accordance with accepted local pra ice and City of Edmonds standards. Soft rock, or rock with a significant number of fractures or I elusions, should not be used, In order to limit the amount of maintenance and repair needed ov time. Provisions for maintenance, such as access to the rockery, should be considered In the VA77ONS AND SLOPES avation slopes should not exceed the limits specified In local, state, and national government sty regulations. Temporary cuts to a depth of about 4 feet may be attempted vertically in 3turated soil, If there are no indications of slope instability. However, vertical cuts should not be le near property boundaries, or existing utilities and structures. Based upon Washington rinistrative Code (WAC) 296. Part N, the soil at the subject site would generally be classified as 3 B. Therefore, temporary cut slopes greater than 4 feet In height cannot be excavated at an nation steeper than 1.1 (Horizontal:Vertical), extending continuously between the top and the �m of a cut. As discussed in the General section of this report, groundwater exiting cut slopes lead to rapid destabilization of the cut. If groundwater is encountered In any of the cuts at the the excavation should be immediately backfilled to above the line of seepage and the ethnical engineer should be called to the site to evaluate the need for remedial measures, above -recommended temporary slope Inclination Is based on what has been successful at sites with similar soil conditions. Temporary cuts are those that will remain unsupported for a vely short duration to allow for the construction of foundations, retaining walls, or utilities. )orary cut slopes should be protected with plastic sheeting during wet weather. The cut slopes Id also be backfilled or retained as soon as possible to reduce the potential for Instability. ,e note that gravel can cave suddenly and without warning. Excavation, foundation, and utility actors should be made especially aware of this potential danger. All permanent cuts Into native soil should be. Inclined no steeper than 2:1 (H:V). Fill slopes should nol be constructed with an inclination greater than 2.5:1 (H:V). To reduce the potential for shallow sic ighing, fill must be keyed and benched into the existing slopes. Adequate compaction of the slo e. face is important for long-term stability and is necessary to prevent excessive settlement of palios, slabs, foundations, or other improvements that may be placed near the edge of the slope. Th can be accomplished by overbuilding the compacted fill and then trimming it back to its final inc ination. Water should not be allowed to flow uncontrolled over the top of any temporary or pe anent slope. Also, all permanently exposed slopes should be seeded with an appropriate ties of vegetation to reduce erosion and improve the stability of the surficial layer of soil, An disturbance to the existing slope outside of the building limits may reduce the stability of the slo e. Damage to the existing vegetation and ground should be minimized, and any disturbed ar as should be revegetated as soon as possible. Soil from the excavation should not be placed on the slope, and this may require the off -site disposal of any surplus soil. GEOTECH CONSULTANTS. INC. Jackson JN 03322 ember 3, 2003 Page 10 We anticipate that cuts on the order of 6 to 8 feet will be required to achieve the proposed finish floor elevations. Based on the setbacks indicated on the site plans, the only locations where there may be Insufficient room within the property lines to make the proposed cuts are on the northern side of the northernmost house and the southern side of the southernmost house. If the house locations or elevations cannot be adjusted to maintain the recommended out slope inclinations, sho ing will be required to make the proposed cuts. We can provide design recommendations for sh Ing if it is necessary. GE CONSIDERATIONS Foundation drains should be installed around the perimeter of each of the residences. We rec mmend that each residence have its own independent foundation drainage system. Drains s Id also be placed at the base of all earth -retaining walls. -These drains should be surrounded by t least 6 inches of 1-inch-minus, washed rock and then wrapped in non -woven, geotextile filter fab ic (Mirafi 140N, Supac 4NP, or similar material). At its highest point, a perforated pipe invert shc uld be at least 6 inches below the bottom of a slab floor or the level of a crawl space, and it shc uld be sloped for drainage. All roof and surface water drains must be kept separate from the fou idation drain system. A typical drain detail is attached to this report as Plate 3. For the best Ion -term performance, perforated PVC pipe is recommended for all subsurface drains. In general, an outlet drain Is recommended for all crawl spaces to prevent a build up of arty water th may bypass the footing drains. We can provide recommendations for interior drains, should thel become necessary, during excavation and foundation construction. Groundwater was observed during excavation of the test pits. If seepage Is encountered in an ex avaflon, it should be drained from the site by directing it through drainage ditches, perforated pip , or French drains, or by pumping it from sumps interconnected by shallow connector trenches at t le bottom of the excavation. Th& excavation and site should be graded so that surface water is directed off the site and away fro the tops of slopes. Water should not be allowed to stand in any area where foundations, sla , or pavements are to be constructed. Final site grading in areas adjacent to the residences sh uld slope away at least 2 percent, except where the area Is paved. Surface drains should be prc vided where necessary to prevent ponding of water behind foundation or retaining walls. Ad itlonally: a drainage swale should be provided upslope of each residence to intercept surface ru -off and direct it into the storm drains. We recommend that catchbasins be placed in each of the driveways to capture surface water and direct it into the storm water system. Water from roof, stc rm water, and foundation drains should not be discharged onto slopes; it should be tightlined to a stable outfall located away from any slopes. EARTHWORK AND STRUCTURAL FILL All building and pavement areas should be stripped of surface vegetation, topsoil, organic soil, and ott er deleterious material. A large amount of dumped garbage and yard waste were observed thr 3ughout the site; these materials will need to be removed during site clearing. The stripped or ret ioved sand and gravel above the root line should not be mixed with any materials to be used as strictural fill, but they could be used in non-structural areas, such as landscape beds. GEOTECH CONSULTANTS, INC. rAltt: 1;I Jackson • :mbar 3, 2003 • JN 03322 Page 11 St ru tural fill is defined as any fill, . including utility backfill, placed under, or close to, a building, beh d permanent. retaining or foundation walls, or in other areas where the underlying soil needs to s pport loads. All structural fill should be placed in horizontal lifts with a moisture content at, or nea , the optimum moisture content. The optimum moisture content is that moisture content that res Its in the greatest compacted dry density. The moisture content of fill is very important and mu be closely controlled during the filling and compaction process. As discussed in the General sec on, the on -site gravel below the root line is suitable for reuse as structural fill. However, we rec mmend that footings be placed on no more than 5 feet of structural fill. allowable thickness of the fill lift will depend on the material type selected, the compaction 3ment used, and the number of passes made to compact the lift. The loose lift thickness Id not exceed 12 inches. We recommend testing the fill as it is placed. If the fill is not ;iently compacted, it can be recompacted before another lift is placed. This eliminates the to remove the fill to achieve the required compaction. The following table presents Timended relative compactions for structural fill: Where: Minimum Relativa compaction IS do Mo. e>a rased In pera" aM of the compacted dry demIty to the mawmum dry densk. as detemdned In accordance with AST1M Test Designadon 01557-91(Modified Proctors. General section should be reviewed for considerations related to the reuse of on -site soils; the Fel below the root line is suitable for reuse as structural fill. Structural fill that will be placed in weather should consist of a coarse, granular soil with a silt or day content of no more than 5 rent. The percentage of particles passing the No. 200 sieve should be measured from that Ion of soil passing the three -quarter -inch sieve. LMITAT/ONS analyses, conclusions, and recommendations contained in this report are based on site iitions as they existed at the time of our exploration and assume that the soil and groundwater iitions encountered In the test pits are representative of subsurface conditions on the site. If subsurface conditions encountered during construction are significantly different from those arved in our explorations, we should be advised at once so that we can review these conditions reconsider our recommendations where necessary. Unanticipated soil conditions are monly encountered on construction sites and cannot be fully anticipated by merely taking soil plea in test pits. GEOTECH CONSULTANTS, INC. V "kar- 1 .7 Jackson • • JN 03322 amber 3, 2003 Page 12 urface conditions can also vary between exploration locations. Such unexpected conditions ently require making additional expenditures .to attain a properly constructed project. It is nmended that the owner consider providing a contingency fund to accommodate such itial extra costs and risks. This is a standard recommendation for all projects. report has been prepared for the exclusive use of Alan Jackson and his representatives for fic application to this project and site, Our recommendations and conclusions are based on rued site materials, and selective engineering analyses. our conclusions and nmendations are professional opinions derived in accordance with current standards of Ice within the scope of our services and within budget and time constraints. No warranty is tsed or implied. The scope of our services does not include services related to construction precautions, and our recommendations are not intended to direct the contractor's methods, iques, sequences, or procedures, except as specifically described in our report for deration in design. AaMMONAL SERVICES In dddition to reviewing the final plans, Geotech Consultants, Inc. should be retained to provide ge ethnical consultation. testing, and observation services during construction. This Is to confirm tha subsurface conditions are consistent with those indicated by our exploration, to evaluate wh ther earthwork and foundation construction activities comply with the general intent of the rec mmendations presented In this report, and to provide suggestions for design changes in the eve t subsurface conditions differ from those anticipated prior to the start of construction. H ver, our work would not include the supervision or direction of the actual work of the co rector and its employees or agents. Also, job and site safety, and dimensional measurements, will the responsibility of the contractor. Sullsequent consultation and testing services during the design and construction phase would be ch"ed on a time -and -materials basis in accordance with terms and conditions of our attached scrinvolve ule of fees and general conditions. This work often includes a review of the geotechnical ass of the plans and interaction with the architect, civil engineer, and structural engineer. Also, n geotechnical observation and testing services during the construction phase, which walso be charged on a time -and -materials basis. Unless otherwise notified by the owner, we wassume that your acceptance of this proposal is also authorization to consult with the design tes required on a Hme-and-materials basis. 1 the construction phase, we will provide geotechnical observation and testing services only requested by you or your representatives. We can only document site work that we actually ie. It is still the responsibility of your contractor or on -site construction team to verify that our mendations are being followed, whether we are present at the site or not. GEOTECH CONSULTANTS. INC. Jackson • J N 03322 amber 3, 2003 Page 13 following plates are attached to complete this report: Plate 1 Vicinity Map Plate 2 Site Exploration Plan Plate 3 - 4 Test Pit Logs Plate 5 Typical Footing Drain appreciate the opportunity to be of service on this project. If you have any questions, or if we be of further service, please do not hesitate to contact us. esm Respectfully submitted, GEOTECH CONSULTANTS, INC. 4T Erin M. Toland Geotechnical Engineer �u5i0,1v EXPIRES 01-31- James H. Strange, Jr., P.E. Geotechnical Project Manager GEOTLCH CONSULTANTS, INC. 3UGNgrISA 1VqTN , M a p AW ate. arfRc" PK t,3 -Xi Ib e�,� ea l 3; UM 1L 2w Is Q i 11 • . ism y` ;f?' 1 _ 10HI11YIO S1 SII �7.,4y urn sv s ' MW� d 31 lY $ tool" rK Arm f Y 1" I ^ t• STIR $ 1 .13 n /as �a� she Y i soon+ a u unnrSUMa it % '( $ K cry ! a r OF" 0 t cl lE'( 24 Q _ h E n w Im laura � rl Y � � � ' r�l s sv s i9• ?. yr VII ' 23 IR EIN N » ' FKL . y 1 WIAr c" OW: CMR f N ..ai::• � 9 �' wr N(M mac, r :1tiN s 9� � r r r a, LItam a (I z6 j i �N R^! �I �I +anx fi = SY I f C.) a 7r _ i ay OR w` Mr r 1 �1 1 sw �^Cy�_VL w �I ~ - ��(q3�: r :: II pia .6 �J` ,•+ a all Q - f1�• I� OI�'Lµ 1 �r Ca ••ta 1Y } ♦ :l1Mp'n. 'Y 1'��i`11116i' �I VICINITY MAP GEOTECH 1230 - 7th Avenue South CONSULTANTS, INC. - Edmonds, Washington Jab Ogre: -• 03322 July 2003 ,Not - Scale P�� 1 tl approximate �,-____�„ rp-sd ' wetland boundary �' TP- i i i it TP-4 proposed SFRs Q ' '-.TP-6 Ld`. y P-3 1 TP- - proposed plat lines i t r ; 1 TP-1 ' I 230 240 SITE EXPLORATION PLAN GEOTECR 1230 - 7th Avenue South coNSUIL'!<'AM,M Edmonds, Washington ✓ ftl •aM& scab plate:03322 July 2003 Not to Scale 2 • • Test Pit 1 0 - 1.0 TOPSOIL Dark brown silty TOPSOIL with abundant roots, dry, loose 1.0 - 5.0 SW Brown SAND with gravel and cobbles, slightly moist, medium -dense 5.0 - 6.0 -becomes dense to very dense *No groundwater encountered, some caving from 0 - 3.0 feet during excavation Test Pit 2 0 - 1.0 FILL Brown sand and gravel FILL, with yard waste, loose 1.0 - 2.0 TOPSOIL Old, black TOPSOIL with abundant roots, dry, loose 2.0 - 4.0 SW Brown SAND with gravel and cobbles, highly weathered, with abundant roots, slightly moist, medium -dense 4.0 - 9.0 Brown, gravelly SAND with cobbles, very moist, dense D groundwater encountered, some caving from 0-2.0 feet during excavation Test Pit 3 0- ,0 TOPSOIL Dark brown silty TOPSOIL with abundant roots, dry, loose, mixed with construction debris incl. 12- inch concrete rubble 1.0 - 6.0 SW Gray -brown SAND with gravel and cobbles, medium -grained, slightly moist, dense 6.0 - 7.0 -with more cobbles, becomes very wet 'Groundwater encountered at 6.5 feet, some caving from 4.0 - 8.0 feet during excavation Test Ptt 4 0- 0.5 TOPSOIL Dark brown silty TOPSOIL with abundant roots, dry, loose 0.5 - 2.0 FILL and TOPSOIL Gray -brown sand FILL with gravel and occasional cobbles, medium -grained, slightly moist, loose to medium -dense, mixed with old TOPSOIL. at 1.5 2.0 feet 2.0 - 5.0 SW Gray -brown SAND with gravel and cobbles, medium -to coarse -grained, very moist, dense 6.0-7.0 -becomes wet "No groundwater encountered, some caving from 4.0 - 6.0 feet during excavation TEST PIT LOGS GEOTECH 1230 - 7th Avenue South CONSULTAM, INC- Edmonds, Washington Jeb No: QAht ,tog,�dpy� p��; 03323 2 Au Z003 fcMt Test Pit 5 u- z.0 TOPSOIL Brown silty TOPSOIL with abundant roots, dry, loose 2.0 - 4.0 SW Gray SAND with gravel and cobbles, moist, medium -dense . 4.0 - 7.0 SP -becomes gray -brawn, medium -grained, wet, dense *Groundwater encountered at 6.0 feet, some caving from S.0 - 7.0 feet during excavation Test Pit 6 .- Description 0- 1.0 TOPSOIL Dark brawn silty TOPSOIL with abundant roots, dry, loose 1.0 - 3.0 SW Gray -brown SAND with gravel and cobbles, moist, medium -dense 3.0 - 6.5 SP -becomes medium -grained, very moist. dense `No groundwater encountered, some caving from 3.0 - 5.0 feet during excavatlon Test Pit 7 0- 2.0 FILL Gray -brown. sand and gravel FILL, dry, loose and Old TOPSOIL 2.0 - 4.0 SW Gray -brown, highly weathered SAND with gravel and cobbles, with occasional roots, slightly moist, medium -dense 4.0 - 7.5 -dense, wet.at 7.0 fleet o groundwater encountered, some caving from 6.0 - 7.0 feet during excavation 'VEST PIT LUGS GEO TECH 1230 - 7th Avenue South CONSMTAN", fNC' Edmonds, Washington .lod Alm Data: Loomed pyatG• 4 03322 August 2003 EM Washed F (7/8" min. a 6" min, NOTES: (1) In cr (2) Refer backfill away from ttion. Provide surface where necessary, Tightline Roof Drain (Do not connect to footing drain) Backfill (See text for „R requirements) Nonwoven Geotextile Filter Fabric SLAB • o o�oQo o Y` � 4 '� 'A� '0.'.°,Q•O.' •p•D.•Q.0.4.• O e • • . • .r;Nif6i• •t f � t ea •o••e••°eae•••so•e"•'0o° °p •V °O �� :iu«..t:nviu. _ s { i` >q �Sr w �'_ .,���: b i' • ti • • tb .. „. b � . s', p ,> � i . ^ •, 4" Perforated Hard PVC Pipe (Invert at least 6 Inches below slab or crawl space. Slope to drain to appropriate outfall. Place holes downward.) Free -Draining Gravel (if appropriate) i spaces, provide an outlet drain to prevent buildup of water that yes the perimeter footing drains. report text for additional drainage and waterproofing considerations. GEOTECH TWICAL DRAM CONSMUM VC 1230 - 7th Avenue South Edmonds, Washington JaebNo D&ft- 23M August 2003 Not to Sole 5 n7iasi[uos ii:oo 4LDf4! 1 i GE TECH CONSPTANTS, INC. i Alah Jackson 1001 Highway 99 Ly nwood, Washington 99037 SAect: Geotechnical Engineering Study Proposed Wilderness Bluff Short Plat 1230 — 7th Avenue South Edmonds, Washington Dear Mr. Jackson: Mu i r-Un f • r"M uL • 13256 Northeast 20th Street Suite 16 . Bellevue, Washington 98005 (425) 747-5618 FAX (as) 747-8561 RECEIVED September 3, 2003 SEP 0 8 2003 JN 03322 DEVELOPMENT SEAVI1E( DUI'LDING SEP 2 2 2003 via facsimile: (425) 787-9112 are pleased to present this *geotechnical engineering report for the proposed single-family dences to be constructed In Edmonds, Washington. The scope of our work consisted of Ioring site surface and subsurface conditions, and then developing this report to. provide )mmendations for general earthwork and design criteria for foundations and retaining walls. s work was authorized by your acceptance of our Contract for Professional Services dated July 2003. W were provided with a preliminary site plan that includes some topographic information. AFM Ind istries, Inc. developed this plan, which is dated September 14, 2002. Based on this plan and on onversations with Alan Jackson, we anticipate that the development will consist of dividing the apF roximately 1.8-acre site into four lots and constructing one single-family residence on each lot. Thy houses will be accessed via driveways off of 7th Avenue South and will be set back 25 feet fro the street. Each house will consist of one floor of living space and a garage over a daylight be ement. Some cuts and fills will be necessary to achieve the proposed finish floor elevation of ap roximately 8 to 10 feet below existing street grade, and a small backyard will be filled at finish Qr elevation. No development is proposed on the western side of the site, as this area is a deslianated wetland. If t e scope of the project changes from what we have described above, we should be provided wit revised plans in order to determine if modifications to the recommendations and conclusions of thi , report are warranted. SITE CONDITION SItFACE Th¢¢ Vicinity Map, Plate 1, illustrates the general location of the site. The undeveloped, wooded site is Ibcated on the western side of 7th Avenue South in Edmonds. The site slopes from east to west, wit elevations varying from approximately 246 feet at the southeastern comer to. approximately 20 feet at the southwestern comer_ Most of the western part of the site is a relatively flat destignated wetland, and there is a creek that winds along the western property line. The proposed development area is located on the sloped, eastern portion of the site. The slopes are inclined at approximately 30 percent and are covered with tall deciduous and evergreen, trees. The ground is -- - — i GEOTECH CONSULTANTS, INC. 1• _ V�r V.iI I.VVJ LI.VV 14Jf•ff VJV♦ Mu IrkM 03 r • ' Alar Jackson JN 03322 Sep ember 3, 2003 Page 2 cov red'with blackberry and morning glory vines near the street and with fems and other low gro h vegetation elsewhere. There is an area on the southem part of the site where app oximately 10 feet of yard waste and construction debris have been dumped to form a locally steeper slope. Dumped garbage, yard waste, and construction debris were observed scattered thro Lighout the site. The adjoining properties are developed with single-family residences. CE Th� subsurface conditions were explored by excavating seven test pits at the approximate Ioc bons shown on the Site Exploration Plan, Plate 2. Our exploration program was based on the proposed construction, anticipated subsurface conditions and those encountered during exploration, and the scope of work outlined in our proposal. Th test pits were excavated on July 24, 2003 with a small, rubber -tracked trackhoe provided and Op led by Alan Jackson. A geotechnical engineer from - our staff observed the excavation process, logged the test pits, and obtained representative samples of the soil encountered. "Grab." samples of selected subsurface soil were collected from the backhoe bucket. The Test Pit Logs are1provided in Plates 3 and 4 of this report. test pits encountered a 6- to 24-inch layer of topsoil and 2 to 3 feet of weathered sand gravel with abundant roots overlying dense to very dense sand and gravel with' cobbles occasional boulders. One to 2 feet of sand and gravel fill was encountered overlying topsoil in Test Pits 1, 4, and 7. The dense to very dense sand and gravel was )untered to the maximum explored depth of 9 feet below existing grade. The depths of layers, including topsoil, that are indicated on the logs are approximate. More exact fition of soil unit thicknesses would require more explorations. Large amounts of yard waste, garbage, and construction debris were observed scattered throughout the site and were encountered in the topsoil and in the fill. This debris will need to be removed during site Gearing. Groundwater seepage was observed at depths of 6 to 6.5 feet in Test Pits 3 and 5; however, the test pits were left open for only a short time. period. Therefore, the seepage levels on the logs represent the location of transient water seepage and may not indicate the static groundwater level. It should be noted that groundwater levels vary seasonally with rainfall and other factors. final logs represent our interpretations of the field logs. The stratification lines on the logs ?sent the approximate boundaries between soil types at the exploration locations. The actual ition between soil types may be gradual, and subsurface conditions can vary between )ration locations. The logs provide specific subsurface information only at the locations tested. relative densities and moisture descriptions indicated on the test pit logs are interpretive riotions based on the conditions observed during excavation. The compaction of backfill was not in the scope of our services. Loose soil will therefore be found in the area of the test pits. If this presents a problem, the• backfill will need to be removed and re laced with structural fill during construction. GEOTECH CONSULTANTS, INC. V W 0.2f svua A f : GO bo" ( M 01 t=u 1 r-%,n I• r'M= 04 Al n Jackson JN 03322 Se tember 3, 2003 Page 3 CONCLUSIONS AND RECOMMENDATIONS SECTION CONTAINS A SUMMARY OF OUR STUDY AND FINDINGS FOR THE PURPOSES OF A 'RAL OVERVIEW ONLY. MORE SPECIFIC RECOMMENDATIONS AND CONCLUSIONS ARE AINED IN THE REMAINDER OF THIS REPORT. ANY PARTY RELYING ON THIS REPORT SHOULD THE ENTIRE DOCUMENT. This proposed development will consist of dividing the site into four roughly equal lots and costructing one single-family residence on each lot. The recommendations presented In this re ort are based on the assumption that the earthwork for all of the houses can be completed at once. If the development plans change, we should be notified so that we may update our redommendations accordingly. test pits conducted for this study encountered loose fill, topsoil, and highly weathered sand and tel overlying dense to very dense sand and gravel. Competent, native soils were encountered Meen 1 and 4 feet below existing grade, with the thicker loose, surficial layer encountered near top of the slope on the eastern side of the site. The native sand and gravel soils encountered ow the root line are competent 'to support the four proposed single-family residences on ventional foundations. These soils are also suitable for reuse as structural fill throughout the The topsoil and weathered sand may be , reused as fill in non-structural areas such as Iscaping beds. Dumped construction debris, yard waste, and garbage were observed uohout the site. This material is not suitable for reuse as fill and should be removed during site Be sed on the topographic Information provided to us, and on our understanding of the project. so ne cuts and fills will be required to achieve the proposed finish floor elevation of 8 to 10 feet be ow existing street grade. Because the proposed houses will be set back at least 25 feet from the edge of the street, cut slopes inclined no steeper than 1:1 (Horizontal:Vertical) can be made wi in the eastern property line. Please note that this inclination applies only to the native sand and gr vel; the fill and debris encountered near the surface on most of the site should be removed du ing site clearing. Also, groundwater was encountered in two of the downslope test pits during ex oration. If groundwater is encountered during the excavation on the upslope side of the site, th cut slopes below the groundwater table will likely experience some sloughing or caving. To mitigate the potential for instability of the cut slopes below the groundwater table, the cuts may ha ve to be backfilled with rock ballast. We should be contacted at once if groundwater is en untered during the excavation of the cut slopes. All cut slopes should be protected im ediately with plastic sheeting and should be monitored daily by the superintendent for inc ications of instability. Soil stockpiles and debris from site clearing should not be stored at the to of any cut slope. foundation walls between the adjacent residences are approximately 10 feet apart as shown the site plan. The soil between the foundation walls of the proposed residences should be loved as part of the mass excavation where it cannot be inclined at 1:1 (H;V). Taking into ount a space allowance of 2 feet on each side for footings, drains, and forms, cuts cannot eed 3 feet between the foundation walls. GEOTECH CONsuLrANTs. INC. alit Clan ZVO.1 t r : 00 Yc:J r r r�i %=U I Cl+n • P pv= VO Alai i Jackson • • JN 03322 . Se tember 3, 2003 Page 4 Ba ed on the site plan, it appears as though cuts on the order of 6 to 8 feet will be necessary to achieve finish floor elevations of the northernmost houses and southernmost. The plan shows eac of these houses set back 5 feet from the northern and southern property lines, respectively. . Because the site soils may be inclined no steeper than 1:1 (H:V) shoring will be required to make the proposed cuts unless the finished floor elevations of these structures are revised. We can Mal -,a recommendations for the design of these temporary shoring walls if they are required. Based on the topographic information provided to us, fill on the order of 6 to 8 feet willbe required to Ilevel the finish floor of each house at its proposed finish floor elevation. However, we recommend that footings be placed on no more than 5 feet of structural fill. Finished fill slopes should not be inclined steeper than 2.5:1 (H:V). Depending on the desired back yard layout and the location of the wetland buffer, it may prove more economical to overexcavate, place the do nslope foundations on native, dense sand and gravel and leave a tall crawl space, or to step the buildings down the slope. Alternatively, a reinforced fill rockery could be constructed near the we tern edge of the development area to level the site. Regardless of which method is chosen, we rec mmend that the downslope foundation wall be designed as a retaining wall to retain the soil within the crawl space or beneath the slab down to the footing level. Fill rockeries taller than 4 feet will Irequire geogrid reinforcement; we can provide a design if necessary. We should review the grading plans once the house layouts are finalized. Th site sand and gravel below the root line is suitable for reuse as structural fill. The earthwork co:ractor should prepare the fill areas by removing the topsoil and highly weathered sand above the root line. The new fill should be benched into the dense native soils by cutting flat benches into the dense native soils. Each horizontal lift of fill should be tested to ensure that adequate corr paction is being achieved. The foundation walls should be backfilled with free -draining structural fill. The site sand and gravel below the root line is acceptable for use as wall backfill. Footing drains should be installed at the bas a of each foundation wall. We recommend that each residence have its own. independent fout idation drainage system, so two separate drains would need to be placed in the backfill beb ween the adjacent houses. Drainage should also be provided behind all retaining walls and Th erosion control measures needed during site development will depend heavily on the weather on ltions that are encountered during construction. Site clearing will expose a large area of bare soil and the erosion potential on the site is moderate due to the slope of the site. We anticipate tha a silt fence will be needed around the downslope sides of any Geared areas and around the wet ands. Straw bales should be placed against the silt fence for added protection during grading. Rocked construction access roads should be extended into the site to reduce the amount of mud car lied off the property by trucks and equipment. Wherever possible, these roads should follow the alig ment of planned pavements. Soil stockpiles should be covered with plastic during wet we Cher. Following rough grading, it may be necessary to mulch or hydroseed bare areas that will not immediately covered with landscaping or an impervious surface. :h Consultants, Inc. should be allowed to review the final development plans to verify that the nendations presented in this report are adequately addressed in the design. Such a plan would be additional work beyond the current scope of work for this study, and it may include is to our recommendations to accommodate site, development, and geotechnical lints that become more evident during the review process. GEOTEck CONSULTANTS. INC. 021LPLVvZ. At Lou YL'Jf Mr�.wa AI • a Jackson S4tember 3, 2003 mu i r_%on � rFi.1t Ob • JN 03322 Page 5 1 recommend including this report, in its entirety, in the project contract documents. This report ild also be provided to any future property owners so they will be aware of our findings .and CONSIDERATIONS The site is located within Seismic Zone 3, as illustrated on Figure No. 16-2 of the 1997 Uniform Building Code (UBC). In accordance with Table 16-J of the 1997 UBC, the site soil profile within 10 feet of the ground surface is best represented by Soil Profile Type Sc (Very Dense Soil). The sit soils are not susceptible to seismic liquefaction because of their dense nature. FOUNDATIONS Th proposed residences can be supported on conventional continuous and spread footings be ring on undisturbed, dense, native sand and gravel, or on up to 5 feet of properly compacted st aural fill placed above this competent native soil. See the section entitled General Earthwork ani Structural Fill for recommendations regarding the placement and compaction of structural fill beneath structures. Adequate compaction of structural fill should be verified with frequent density tes ng during fill placement. Prior to placing structural fill beneath foundations, the excavation shc uld be observed by the geotechnical engineer to document that adequate bearing soils have bef n exposed.. We recommend that continuous and individual spread footings have minimum widths of 16 and 18 inches, respectively. Footings should also be bottomed at least 18 inches below the lowest adjacent finish ground surface. The local building codes should be reviewed to det' rmine if different footing widths, or embedment depths are required. Footing subgrades must belcleaned of loose or disturbed soil prior to pouring concrete. Depending upon site and eq Ppment constraints, this may require removing the disturbed soil by hand. An lallowable bearing pressure of 2,000 pounds per square foot (psf) is appropriate for footings supported on the dense, native sand and gravel found below the root line or on structural fill placed ab a these competent native soils. A e-third increase in this design bearing pressures may be used when considering short-term wi or seismic loads. For the above design criteria, it is anticipated that the total post -construction se ement of footings founded on competent, native soil, or on structural fill up to 5 feet in thi ness, will be about one-half inch, with differential settlements on the order of one-half inch in a dis nce of 50 feet along a continuous footing with a uniform load. the fou levc `;ral loads due to wind or seismic forces may be resisted by friction between the foundation and bearing soil, or by passive earth pressure acting on the vertical, embedded portions of the idation. For the latter condition, the foundation must be either poured directly against relatively it, undisturbed soil or be surrounded by level structural fill. We recommend using the following late values for the foundation's resistance to lateral loading: GEOTECM CONSULTANTS. INC. nr,F�. If Jackson • amber 3, 2003 PARAMETER ULTIMA VALUE Coefficient of Friction 0.40 Passive Earth Pressure 250 pcf Where: (1) pcf is pounds per cubic foot, and (if) passive earth pressure is computed using the equivalent fluid density. rpv= v r JN 03322 Page 6 e ground in front of a foundation is loose or sloping, the passive earth pressure given above will be appropriate and we should be contacted for a revised. recommendation. We recommend staining a safety factor of at least 1.5 for the foundation's resistance to lateral loading, when a the above ultimate values. FOUNDATION AND RETAINING WALLS ping walls backfilled on only one side should be designed to resist the lateral earth pressures sed by the soil they retain. The following recommended parameters are for walls that restrain . backfill: PARAMETER 30 pct Active Earth Pressure,* Passive Earth Pressure 300 pcf Coefficient of Friction 0.40 Soil Unit Weight 135 pef Where: (i) pef is pounds per cubic foot, and (if) active and passive earth pressures are computed using tha equivalent fluid pressures. ' For a restrained wall that cannot deflect at least O.M times its height, a uniform lateral pressure equal to 10 psf times the height of the wall should be added to the above active equivalent fluid pressure. values given above are to be used to design permanent foundation and retaining walls only. passive pressure given is appropriate for the depth of level structural fill placed in front of. a ining or foundation wall only. The values for friction and passive resistance are ultimate values do not Include a safety factor. We recommend a safety factor of at least 1.5 for overtuming sliding, when using the above values to design the walls. Restrained wall soil parameters . old be utilized for a distance of 1.5 times the wall height from corners or bends in the walls. is intended to reduce the amount of cracking that can occur where a wall is restrained by a er. design values given above do not include the effects of any hydrostatic pressures behind the and assume that no surcharges, such as those caused by slopes, vehicles, or adjacent iatlons will be exerted on the walls. If these conditions exist, those pressures should be added GEOTECM CONSULTANTS. INC. CO7I VJf LVNJ Lf. NO YLJ( 464 tMUI QIIM )• - rWUt, bt( Alar Jackson • • JN 03322 September 3, 2003 Page 7 to tt a above lateral soil pressures. Where sloping backfill is desired behind the walls, we will need to given the wall dimensions and the slope of the backfill in order to provide the appropriate desqgn earth pressures. The surcharge due to traffic loads behind a wall can typically be acc6unted for by adding a uniform pressure equal to 2 feet multiplied by the above active fluid de4ty; a traffic surcharge should be applied to the eastern foundation wall of each residence. He construction equipment should not be operated behind retaining and foundation walls within a di tance equal to the height of a wall, unless the walls are designed for the additional lateral pre ures resulting from the equipment The wall design criteria assume that the backfill will be Wei compacted in lifts no thicker than 12 inches. The compaction of backfill near the walls should be'ccomplished with hand -operated equipment to prevent the walls from being overloaded by the higher soil forces that occur during compaction. ' ckfill placed behind retaining or foundation walls should be coarse, free -draining uctural fill containing no organics. This backfill should contain no more than 5 percent silt clay particles and have no gravel greater than 4 inches in diameter. The percentage of rtides passing the No. 4 sieve should be between 25 and 70 percent. The native sand I gravel encountered below the root line during our explorations is suitable for reuse as ainina wall backfill. ie purpose of these backfill requirements is to ensure that the design criteria for a taining wall are not exceeded because of a build-up of hydrostatic pressure behind the all. The top 12 to 18 inches of the backfill should consist of a compacted, relatively ipermeable soil or topsoil, or the surface should be paved.. The ground surface must also )pe away from backfilled walls to reduce the potential for surface water to percolate into e backfill. The section entitled General Earthwork and Structural Fill contains commendations regarding the placement and compaction of structural fill behind retaining id foundation walls. e above recommendations are not intended to waterproof the below -grade walls. The rformance of subsurface drainage systems will degrade over time. Therefore, iterproofing should be provided where moist conditions or some seepage through the ills are not acceptable in the future. This typically includes limiting cold -joints and wall netrabons, and using bentonite panels or membranes on the outside of the walls. plying a thin coat of asphalt emulsion is not considered waterproofing, but will only help prevent moisture, generated from water vapor or capillary action, from seeping through concrete. With any project, adequate ventilation of basement and crawl space areas is mrtant to prevent a build up of water vapor that may be transmitted through concrete Its from the surrounding soil. The building floors may be constructed as slabs -on -grade atop the native sand and gravel, or on st ural fill. The subgrade soil must be in a firm, non -yielding condition at the time of slab con truc Lion or underslab fill placement. Any soft areas encountered should be excavated and replaced with select, imported structural fill. GEOTECH CONSULTANTS. INC. _. -- ""'• • fir• • 1 I�IV V J Is Ala Jackson JN 03322 Se ember 3, 2003 Page 8 All 1 labs -on -grade should be underlain by a capillary break or drainage layer consisting of a minimum 4-inch thickness of coarse, free -draining structural fill with a gradation similar to that discussed in Permanent Foundation and Retaining Walls. As noted by the American Concrete Inst tute (ACI) in Section 3.2.3 of the Guides for Concrete Floor and Slab Structures, proper. moi tune protection is desirable immediately below any on -grade .slab that will be covered by tile, wo d, carpet, impermeable floor coverings, or any moisture -sensitive equipment or products. ACI aisc notes that vapor retarders, such as 6-mil visqueen, are typically used. A vapor retarder is deft ied as a material with a permeance of less than 0.3 US perms per square foot_ (pso per hour, as etermined by ASTM E 96. It is possible that concrete admixtures may meet this specification, althppugh the manufacturers of the admixtures should be consulted. However, if no potential for vapor passage through the slab is desired, a vapor barrier should be used. A vapor barrier, as defined by ACI, is a product with a water transmission rate of 0.00 perms per square foot per hour whgn tested in accordance with ASTM E 96. Reinforced membranes having sealed overlaps can metpt this requirement. In the recent past, ACI (Section 4.1.5) recommended that a minimum of 4 inches of well -graded conipactable granular material, such as a 5/8 inch minus crushed rock pavement base, should be placed over the vapor retarder or barrier for protection of the retarder or barrier and as a "blotter" to aid in the curing of the concrete slab. Sand was not recommended by ACI for this purpose- Hov rever, the use of material over the vapor retarder is controversial as noted in current ACI liter ture because of the potential that the protection/blotter material can become wet between the time of its placement and the installation of the slab. if the material is wet prior to slab placement, which is always possible in the Puget Sound area, it could cause vapor transmission to occur up through the slab in the future, essentially destroying the purpose of the vapor barrier/retarder. Th refore, if there is a potential that the protection/blotter material will become wet before the slab is installed, ACI now recommends that no protection/blotter material be used. However, ACI then recommends that, because there is a potential for slab cure due to the loss of the blotter material, join spacing in the slab be reduced, a low shrinkage concrete mixture .be used, and "other me cures" (steel reinforcing, etc.) be used. ASTM E-1643-98 "Standard Practice for Installation of W4er Vapor Retarders Used in Contact with Earth or Granular Fill Under Concrete Slabs" gerrierally agrees with the recent ACI literature. W recommend that the contractor, the project materials engineer, and the owner discuss these iss les and review recent ACI literature and ASTM E-1643 for installation guidelines and guidance on the use of the protection/blotter material. Our opinion is that with impervious surfaces that all me. ns should be undertaken to reduce water vapor transmission. Wd anticipate that rockeries may be used to level the backyards. At least 12 inches of quarry spAs should be placed behind rockeries to reduce the potential for soil eroding through them. A per1Forated drain pipe surrounded by drain rock should be installed behind the rockeries. Wrecommend limiting fill rockeries to a height of 4 feet and constructing them on only competent nat ve soil. The lower two-thirds of the rockery should be constructed with 3- to 4-man rocks and the fill should be placed and compacted to structural fill requirements. Prior to rockery co struction, the fill should be placed beyond the planned rockery location and then cut nearly ve ical so that the soil in back of the rockery is thoroughly compacted. Since grading plans were no established at the time of this report, the relationship between the proposed footings and ---------GEOTECH-CONSULTANTS; INC. --- ------ 477/ OJ/ Z1 vj 1 / : VU 4ZU r41�1 Jackson • amber 3, 2003 tLU 1 CI■R 1• r "M 113 • JN 03322 Page 9 iosed rockeries could not be determined. Foundations closer to the back of the rockery than times the height of the rockery would exert a surcharge on the adjacent rockeries; surcharged eries or rockeries taller than 4 feet will require the use of geogrid reinforcement in the backfill. can provide a rockery detail if necessary. Th construction of rockeries Is, to a large extent, an art not entirely controllable by engineering me hods and standards. It is imperative that rockeries, if used, are constructed with care and in a pro r manner by an experienced contractor with proven ability in rookery construction. The rookeries should be constructed with hard, sound, durable rock in accordance with accepted local pra ice and City of Edmonds standards. Soft rock, or rock with a significant number of fractures or i iclusions, should not be used, In order to limit the amount of maintenance and repair needed ov4 time. Provisions for maintenance, such as access to the rockery, should be considered in the VA77ONS AND SLOPES Exsavation slopes should not exceed the limits specified in local, state, and national government safety regulations. Temporary cuts to a depth of about 4.feet may be attempted vertically in unsaturated soil, if there are no indications of slope instability. However, vertical cuts should not be mafle near property boundaries, or existing utilities and structures. Based upon Washington Ad inistrative Code (WAC) 296, Part N, the soil at the subject site would generally be classified as Ty B. Therefore, temporary cut slopes greater than 4 feet. in height cannot be excavated at an incl nation steeper then. 110 (Horizontal:Vertical), extending continuously between the top and the bo om of a cut. As discussed in the General section of this report, groundwater exiting cut slopes ca lead to rapid destabilization of the cut. If groundwater is encountered in any of the.cuts at the sit , the excavation should be immediately backfilled to above the line of seepage and the ge _technical engineer should be called to the site to evaluate the need for remedial measures. above -recommended temporary slope. inclination Is based on what has been successful at sites with similar soil conditions. Temporary cuts are those that will remain unsupported for a vely short duration to allow for the construction of foundations, retaining walls, or utilities. )orary cut slopes should be protected with plastic sheeting during wet weather. The cut slopes Id also be backfilled or retained as soon as possible to reduce the potential for instability, ie note that gravel can cave suddenly and without warning. Excavation, foundation, and utility actors should be made especially aware of this potential danger. All permanent Cuts into native soil should be inclined no steeper than 2:1 (H:V). Fill slopes should nol be constructed with an inclination greater than 2.5:1 (H:V). To reduce the potential for shallow slo ighing, fill must be keyed and benched into the existing slopes. Adequate compaction of the slo a face is important for longAerm stability and is necessary to prevent excessive settlement of pa ios, slabs, foundations, or other improvements that may be placed near the edge of the slope. Th s can be accomplished by 'overbuilding the compacted fill and then trimming it back to its final Inc ination. Water should not be allowed to flow uncontrolled over the top of any temporary or pe anent slope. Also, all permanently exposed slopes should be seeded with an appropriate species of vegetation to reduce erosion and improve the stability of the surficlal layer of soil. An� disturbance to the existing slope outside of the building limits may reduce the stability of the s1010e. Damage to the existing vegetation and ground should be minimized, and any disturbed areas should be revegetated as soon as possible. Soil from the excavation should not be placed onIthe slope, and this may require the off -site disposal of any surplus soil. - - - GEOTECH CONSULTA . _ .._ _.-__ low osi 2lona 1 f : lots QZ0 I L*_U I LUH PAGE 11 • Alai i Jackson JN 03322 September 3, 2003 Page 10 We anticipate that cuts on the order of 6 to 8 feet will be required to achieve the proposed finish floo elevations. Based on the setbacks indicated on the site plans, the only locations where there maj be insufficient room within the property lines to make the proposed cuts are on the northern sid of the northernmost house and the southern side of the southernmost house. If the house Io tions or elevations cannot be adjusted to maintain the recommended cut slope inclinations, sho ing will be, required to make the proposed cuts. We can provide design recommendations for s Ing if it is necessary. CONSIDERATIONS Foundation drains should be installed around the perimeter of each of the residences. We recommend that each residence have its own independent foundation drainage system. Drains should also be placed at the base of all earth -retaining walls. -These drains should be surrounded by at least 6 inches of 1-inch-minus, washed rock and then wrapped in non -woven, geotextile filter fabiric (Mirafi 140N, Supac 4NP, or similar material). At its highest point, a perforated pipe invert shc utd be at least 6 inches below the bottom of a slab floor or the level of a crawl space, and It shc uld be sloped for drainage. All roof and surface water drains must be kept separate from the fou idation drain system. A typical drain detail is attached to this report as Plate 3. For the best long-term performance, perforated PVC pipe is recommended for all subsurface drains. In general, an outlet drain is recommended for all crawl spaces to prevent a build up of any water that may bypass the footing drains. We can provide recommendations for interior drains, should they become necessary, during excavation and foundation construction. Gr undwater was observed during excavation of the test pits. If seepage is encountered in an. ex avation, it should be drained from the site by directing it through drainage ditches, perforated pip , or French drains, or by pumping it from sumps interconnected by shallow connector trenches at a bottom of the excavation. The excavation and site should be graded so that .surface water is directed off the site and away fro I the tops of slopes. Water should not be allowed to stand in any area where foundations, sla s, or pavements. are to be constructed. Final site grading in areas adjacent to the residences sh uld slope away at least 2 percent, except where the area is paved. Surface drains should be provided where necessary to prevent ponding of water behind foundation or retaining walls. Additionally, a drainage swale should be provided upslope of each residence to intercept surface ru -off and direct it into the storm drains. We recommend that catchbasins be placed in each. of th driveways to capture surface water and direct it into the storm water system. Water from roof, st water, and foundation drains should not be discharged onto slopes; it should be tightlined to a unable outfall located away from any slopes. EARTHWORK AND STRUCTURAL FILL All building and pavement areas should be stripped of surface vegetation, topsoil, organic soil, and ott er deleterious material. A large amount of dumped garbage and yard waste were observed throughout the site; these materials will need to be removed during site clearing. The stripped or rei ioved sand and gravel above, the root line should not be mixed with any materials to be used as str ictural fill, but they could be used in non-structural areas, such as landscape beds. - - - - - GEOTECH-CONSULTANTS, INC. Ow V it ivaj 1 / : Ot! 4:tO (4 1 ULU I ECH i PAGE 12 l Alan Jackson JN 03322 Sep {ember 3. 2003 Page 11 Stru tural fill is defined as any fill, including utility backfill, placed under, or close to, a building, behind permanent retaining or foundation walls, or in other areas where the underlying soil needs to s pport loads. All structural fill should be placed in horizontal lifts with a moisture content at, or nea 1, the optimum moisture content. The optimum moisture content is that moisture content that resk Its in the greatest compacted dry density. The moisture content of fill is very important and mur, t be closely controlled during the filling and compaction process. As discussed in the General sec on, the on -site gravel below the root line is suitable for reuse as structural fill. However, we rec .mmend that footings be placed on no more than 5 feet of structural fill. allowable thickness of the fill lift will depend on the material type selected, the compaction )ment used, and the number of passes made to compact the lift. The loose lift thickness Id not exceed 12 inches. We ' recommend testing the fill as it is placed. If the fill is not ;iently compacted, it can be recompacted before another lift is placed: This eliminates the to remove the fill to achieve the required compaction. The following table presents emended relative compactions for structural fill: Where: Minimum Relative Compaction is the ratio, expressed in percentages, or the compacted dry density to the maximum dry density, as detemdned in accordance with ASTM Test Designation 01557.91 (Modlbed P►octor). General section should be reviewed for considerations related to the reuse of on -site soils; the ,el below the root line is suitable for reuse as structural fill. Structural fill that will be placed in weather should consist of a coarse, granular soil with a silt or day content of no more than 5 ,ent. The percentage of particles passing the No. 200 sieve should be measured from that Ion of soil passing the three -quarter -inch sieve. LlM/TAT10N5 The analyses, conclusions, and recommendations contained in this report are based on site co ditions as they existed at the time of our exploration and assume that the soil and groundwater co ditions encountered in the test pits are representative of subsurface conditions on the site. If th subsurface conditions encountered during construction are significantly different from those ob erved in our explorations, we should be advised at once so that we can review these conditions anal reconsider our recommendations where necessary. Unanticipated soil conditions are col monly encountered on construction sites and cannot be fully anticipated by merely taking soil sa pies in test pits. GEOTECH CONSULTANTS,-INC---- "I oilL101 1/:Do 4L014 1 L*-UltL;H PAGE 13 Afar Jackson. JN 03322 Sep [ember 3, 2003 Page 12 Sub urface conditions can also vary between exploration locations. Such unexpected conditions freq ently require making additional expenditures .to attain a properly constructed project. It is recc mmended that the owner consider providing a contingency fund to accommodate such potgntial extra costs and risks. This is a standard recommendation for all projects. report has been prepared for the exclusive use of Alan Jackson and his representatives for fic application to this project and site. Our recommendations and conclusions are based on ved site materials, and selective engineering analyses. Our conclusions and nmendations are professional opinions derived in accordance with current standards of Ice within the scope ofour services and within budget and time constraints. No warranty is ssed or implied. The scope of our services does not include services related to construction precautions, and our recommendations are not intended to direct the contractor's methods, iques, sequences, or procedures, except as specifically described in our report for deration in design. ADDITIONAL SERVICES In Idition to reviewing the final plans, Geotech Consultants, Inc. should be retained to provide ge echnical consultation, testing, and observation services during construction. This is to confirm tha subsurface conditions are consistent with those indicated by our exploration, to evaluate w ther earthwork and foundation construction activities comply with the general intent of the rec mmendations presented in this report, and to provide suggestions for design changes in the eve t subsurface conditions differ from those anticipated prior to the start of construction. Ho ver, our work would not include the supervision or direction of the actual work of the co ractor and its employees or agents. Also, job and site safety, and dimensional measurements,. will the responsibility of the contractor. Subsequent consultation and testing services during the design and construction phase would be ch ed on a time -and -materials basis in accordance with terms and conditions of our attached sch Jule of fees and general conditions: This work often includes a review of the geotechnical as s of the plans and interaction with the architect, civil engineer, and structural engineer. Also, it 1 y involve geotechnical observation and testing services during the construction phase, which would also be charged on a time -and -materials basis. Unless otherwise notified by the owner, we world assume that your acceptance of this proposal is'also authorization to consult with the design Win as required on a time -and -materials basis. ng the construction phase, we will provide geotechnical observation and testing services only n requested by you or your representatives. We can only document site work that we actually ;rve. It is still the responsibility of your contractor or on -site constniction team to verify that our mmendations are being followed, whether we are present at the site or not. - GEOTECH CONSULTANTS.-INC. - .V JI VJ/ iyyJ L f . yy `f6J f y Ala Jackson Se ember 3, 2003 t Alit 14 J N 03322 Page 13 following plates are attached to complete this report: Plate 1 Vicinity Map Plate 2 Site Exploration Plan Plate 3 - 4 Test Pit Logs Plate 5 Typical Footing Drain appreciate the opportunity to be of service on this project. If you have any questions, or if we be of further service, please do not hesitate to contact us. Respectfully submitted, GEOTECH CONSULTANTS. INC. Erin M. Toland Geotechnical Engineer esm EXPIRES 01-31= Q r� James H. Strange, Jr., P.E. Geotechnical Project Manager GEOTECH CONSULTANTS, INC. n IFI y9.am+*� JAI9A A rx ;. Qm� r ;' wn _ jlr n hnl6t fs e t Y if i a l�{ Ar -u+ allUst � ! k 61j S s N AI N aag At AY e1�Re a'? 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AY IIle6 �S'+�'� �� ti � fl AV V• Y 6 $roi £ t► "' �'r� #q, �w � U _uiil' AV �•a� � N _ i •Ya3 - . _ y fil. n file if _ m { dtTdi A Ni9 w - T - ^ hl' AT rw MCI Y W AtZpd,E' s L �s iii9 l'�f U �\Q.�' R to __ �— ? YY s His nc R ilk if quaA AM A1!oac var W z - b �h _ v tr. # e& C, n mo t t • •VJ/ VJ/'LVVJ L f � VV ♦iJl4Oi • k 9 wh ' approximate wetland boundary proposed plat lines GEOTECH CONSULTANTS, M l� tLIJ 1 Ct,R , TP-5 d TP- ; TP.4 proposed SFRs s TP-6 i t i i P-3 , TP- i I p i TP-1 i 230 240 PAUL 16 SITE EXPLORATION PLAN 1230 - 7th Avenue South Edmonds, Washington Jab0 22 2003 SNGRIIIr Scale PJA 2 0 co. m c m , � � VJf VJf iVVJ i f . VV 1L JVi • taGu � «,n rbigC, 1 f a Test Pit 1 0 - 1.0 TOPSOIL Dark brown silty TOPSOIL with abundant roots, 1.0 - 5.0 dry, loose Brown SAND with gravel and cobbles, slightly moist, medium -dense 5.0 - 6.0 -becomes dense to very dense 'No groundwater encountered, some caving from 0 - 3.0 feet during excavation Test Pit 2 0 - 1.0 .1.0 - 2.0 TOPSOIL 2.0 - 4.0 Sw 4.0 - 9.0 "No groundwater encountered, some Test Pit 3 0- 1 ,0 TOPSOIL 1.0 - 6.0 Sw t 6.0 7.0 'Groundwater encountered at 6.5 Test Pit 4 Brown sand and gravel FILL, with yard waste, loose Old, black TOPSOIL with abundant roots, dry, loose Brown SAND with gravel and cobbles, highly weathered, with abundant roots, slightly moist, medium -dense Brown, gravelly SAND with cobbles, very moist, dense aving from 0-2.0 feet during excavatlon L)arit brown silty TOPSOIL with abtmdant roots, dry, loose, mixed with construction debris incl. 12- inch concrete rubble Gray -brown SAND with gravel and cobbles, medium -grained, slightly moist, dense -with more cobbles, becomes very.wet some caving from 4.0 - 6.0 feet during excavation 0- 0.5 TOPSOIL Dark brownsilty, TOPSOIL with abundant roots, 0.5 - 2.0 FILL and TOPSOIL Gray -brown sand FILL with gravel and occasional cobbles, medium -grained, slightly moist, loose to medium -dense, mixed with old TOPSOIL, at 1.5 -. 2.0 feet 2.0 - 5.0 Sw Gray -brown SAND with gravel and cobbles, 6.0-7.0 medium -to coarse -grained, very moist, dense 'No groundwate-becomes wet r encountered, some caving from 4.0 - 6.0 feet during excavation TEST PIT L ccxvsu><.OGS NSM Tas' INC TE CH 1230 - 7th Avenue South Edmonds, Washington �� �•� ✓ob No:I Dam I.ogEled g; Platy: . 03M2 I August.2003 EMT 3 L" _-a ... ... Iry I-- i -M_ • w r Lul l I _ r p4%= 10 Test Pit 5 0- 2.0 r2.0 - 4.0 4.0 - 7.0 TOPSOIL SW SP Brown silty TOPSOIL with abundant roots, dry, loose Gray SAND with gravel and cobbles, moist, medium -dense -becomes gray -brown, medium -grained, wet, dense "Groundwater encountered at 6.0 feet, some caving from 6.0 - 7.0 feefduring excavation Test Pit 6 ■-. i- 0- 1.0 71.0-3.0 TOPSOIL Dark brown silty TOPSOIL with abundant roots, dry, loose SW Gray -brown SAND with gravel and cobbles, moist, medium -dense 3.0 - 6.5 SP -becomes medium- rained, very moist,dense 'No groundwater encountered, some caving from 3.0 - 5.0 feet during excavation ..Test Pit 7 0- 2.0 FILL Gray -brown. sand and gravel FILL; dry, loose and Old TOPSOIL - 2.0 - 4.0 SW Gray -brown, highly. weathered SAND with gravel and cobbles, with occasional roots, slightly moist, medium -dense 4.0 - 7.5 -dense, wet.at 7.0 fleet 'No groundwater encountered, some caving from 6.0 - 7.0 feet durina exmvat;e;n TEST PIT LOGS GEOTECH 1230 - 7th Avenue South CONSULTANTS, rive Edmonds, Washington �-- roe No. Dares LoggeA�r• v�rc• 03322 August 2003 EMT 4 i 4 i IWashed (7/8" min. 6" min backfill away from ition. Provide surface where necessary. Backfill (See text for requirements) Nonwoven Geotextile Filter Fabric -0 .A 40.60 Tightline Roof Drain (Do not connect to footing drain) SLAB yy 0 O W� 0 iiyi:. b �- 1. e.� .p �� • 4" Perforated Hard PVC Pipe (Invert at least 6 inches below slab or crawl space. Slope to drain to appropriate ou"I. Place holes downward.) I n a J 0 F�'�'ep�.�•• Free -Draining Gravel (if appropriate) NOTES: (1) In cm spaces, provide an outlet drain to prevent buildup of water that bypa ses the perimeter footing drains. (2) Refer o report text for additional drainage and waterproofing considerations. GE.OTECH TYPICAL DRAIN DETAIL CONSIXTa rr DQr- 1230 - 7th Avenue South Edmonds, Washington - Job Ab: Scapa P/aft 03322 August 2003 Not to scale 5 I CI CITY OF EDMONDS 121 5TH AVENUE NORTH, EDMONDS, WA 98020 PLANNING DIVISION FINDINGS, CONCLUSIONS, AND DECISION To! File S-2003-34 From: d)� athleen T Associate Planner Date: JULY 2, 2003 File: S-2003-34 Wilderness Bluff Property Owner: Brian & Delores Buchea Applicant: Alan Jackson TABLE OF CONTENTS Section Page I. INTRODUCTION............................................................... 2 ....................... A. Application....................................................................................................................................... 2 B. Decision........................................................................:.... 2 H. FINDINGS OF FACT AND CONCLUSIONS................................................................... A. Analysis of Design: Compliance with ECDC 16.20............................................................. ............ 3 B. Conformance to Comprehensive Plan............................................................................................... 3 C. Critical Areas Review: Compliance with ECDC 20.15B.................................................................. 4 D. Wetland Buffer Averaging: Compliance with ECDC 20.15B.080B................................................ 5 E. Subdivision Review Criteria: Compliance with ECDC 20.75.085.................................................... 6 F. Public Comments............................................................... III. RECONSIDERATION AND APPEALS............................................................................ A. Request for Reconsideration............................................................................................................. 7 B. Appeals............................................................................................................................................. 7 C. Timeframes........................................................................:........... 1V. LAPSE OF APPROVAL.....................................................................................................8 V. NOTICE TO COUNTY ASSESSOR..................................................................................8 VI. APPENDICES..................................................................................... VII. PARTIES OF RECORD .......................................... ...............8 OCT 17 2003 DEVELOPMENT SEPVlCES C'R. %1'fY OF G'.,,C ,JJ Staff Report • Wilderness Bluff File No. S-2003-34 t Page 2 of 8 + I. INTRODUCTION A. Application 1. Applicant: Alan Jackson (See Attachment 2.) 2. Site Location: 1230 7m Ave S (See Attachment 1.) 3. Request: To subdivide a 77,106 square -foot lot into 4-lots. There is a category 2 Wetland on -site. The applicant requests to increase the wetland buffer in some areas while decreasing it in other areas —referred to as wetland buffer averaging in the Edmonds Community Development Code. 4. Review Process: Following the public comment period, Planning Staff reviews the request pursuant to the Edmonds Community Development Code makes an administrative decision. 5. Major Issues: a. Compliance with Edmonds Community Development Code (ECDC) Chapter 16.20, Single -Family Residential. b. Compliance with the Comprehensive Plan. c. Compliance with ECDC Chapter 20.15B, Critical Areas. d. Compliance with ECDC Section 20.15B.080B, Wetland Buffer Averaging. e. Compliance with ECDC Section 20.75.085, Subdivision Requirements. Note: All code sections referenced in this report can be viewed via the City's website www.ci.edmonds.wa.us. B. Decision Based upon the Findings of Fact and Conclusions, and considering the Attachments and Exhibits submitted with the application and during the comment period, the following is the decision of the City of Edmonds Planning Division: The Subdivision is APPROVED with the following conditions: Prior to Recording: 1. Prior to construction of engineering requirements, fencing must be installed to protect the critical areas and related buffer. 2. Complete the Engineering Division conditions, listed as "Required prior to Recording" on Attachment 4. 3. Complete removal of debris and revegetation of wetland as required by Attachment 11 or bond for the improvements. 4. Revise short plat map to reflect Critical Areas Easement across Lots 1 through 4. Language should be added to the face of the plat map, stating the limitations of the critical areas easement. Contact the Planning Division for a copy of the standard language. 5. Revise the final short plat document to include signature blocks for the property owners, City of Edmonds Planning Division and City of Edmonds Engineering Division. Also add standard language as required by the Engineering Division 6. Add rebar/stakes to all new property comers. 7. Submit copies of the final short plat documents for review and approval with a current title report. 8. Record short plat documents with the Snohomish County Auditor. 9. After recording, provide three copies of the final recorded short plat to City of Edmonds Planning Division. July 2, 2003 / Staff Report • Wilderness Bluff File No. 5-2003-34 Page 3 of 8 Prior to issuance of any building permit: 1. Complete the Engineering Division conditions, listed as "Required with Building Permit" on Attachment 4. 2. Submit a geotechnical reports which demonstrates compliance with ECDC Title 19 regarding landslide hazard areas. 3. Demonstrate compliance with the recommended mitigation measures of the Landau Associates Critical Areas Report dated 5/8/03. Refer to Attachment 11. Permanent fencing must be installed and signage is required for critical area and buffers. II. FINDINGS OF FACT AND CONCLUSIONS A. Analysis of Design: Compliance with ECDC 16.20. 1. Zoning: The subject property is zoned RS-6 (Single -Family Residential). Compliance with the RS-6 standards is documented below. 2. Lot sizes and dimensions: a) Proposed number of lots: 4 b) Proposed Lot sizes: Lot Area (Minimum 6,000) Lot 1 19,639 Square Feet Lot 2 19,275 Square Feet Lot 3 19,277 Square Feet Lot 4 18,916 Square Feet Lot Width (60 Feet Rea.) 66.3 Feet 66.3 Feet 66.3 Feet 66.3 Feet c) Areas. Setbacks and Lot Width: Lot areas and width for all of the proposed lots are adequate for the RS-6 zone. Setbacks for all future development should be as follows: Lots 1, 2, 3, 20' Street Setbacks: From the east property line and 4 5' Side Setbacks: From north and south property lines 15' Rear Setback: The rear setback is not applicable, because it falls within the wetland. However, a 15' building setback will be required from the edge of the buffer. Refer to Attachment 11. d) Comer Lots: Not applicable e) Flag Lots: Not applicable 3. Lot arrangement to topography: Satisfactory. B. Conformance to Comprehensive Plan 1. Facts: The subject property falls within the single-family small lot designation. Refer to the following Residential Development policies: July 2, 2003 / Staff Report • Wilderness Bluff File No. S-2003-34 Page 4 of 8 a) B.1. Encourage those building custom homes to design and construct homes with architectural lines which enable them to harmonize with the surroundings, adding to the community identity and desirability. b) B.3. Minimize encroachment on view of existing homes by new construction or additions to existing structures. c) B.5.c. Stable property values must not be threatened by view, traffic or land use encroachments. 2. Facts: The applicant is proposing to leave the wetland and buffer area completely undisturbed. The Comprehensive Plan also cites goals and policies directly related to preserving open space. a) Goal. Open space must be seen as an essential element determining the character and quality of the urban and suburban environment, in accordance with the following policies. b) B.2. All feasible means should be used to preserve the following open spaces: lands which have unique scientific or educational values; areas which have an abundance of wildlife particularly where there are habitats of rare or endangered species; natural and green belt areas adjacent to highways and arterials with priority to highways classified as scenic; areas which have steep slopes or are in major stream drainage ways, particularly those areas which have significance to Edmonds residents as water sheds; land which can serve as buffers between residential and commercial or industrial development; bogs and wetlands; land which can serve as buffers between high noise environments and adjacent uses; lands which would have unique suitability for future recreational uses both passive and active; areas which would have unique rare or endangered types of vegetation. c) B.3. Open space would be distributed throughout the urban areas in such a manner that there is both visual relief and variety in the pattern of development and that there is sufficient space for active and passive recreation. Provide views and open space in areas of high density or multiple housing by requiring adequate setback space and separation between structures. 3. Conclusions: The proposed division of the lots complies with the comprehensive plan policies. C. Critical Areas Review: Compliance with ECDC 20.15B. 1. Critical Areas Review number: CA-97-59 Study Required 2. Results of Critical Areas Review: Staff visited the site and determined that further study would be necessary to determine the presence of a steep slope hazard area and/or a wetland and stream as defined by ECDC 20.15B. a) Based on the topographic map submitted by the applicant, prepared by AFM Industries, the slope does not qualify as steep slope hazard area, per ECDC 20.15B.060A3c. Rather it appears to qualify as a landslide hazard area per ECDC 20.15B.060A3b. At time of building permit application for each of the lots, the applicant must submit the required soils report and related geologic information as required by ECDC Title 19. b) In terms of the wetland potential, the applicant entered into a three party contract with the City of Edmonds and Landau Associates, as required by ECDC 20.15B.140D. Landau conducted the review and concluded that a Category 2 wetland exists on site. Refer to the map in Attachment 11. The map delineates the edge of the wetland and identifies a 50- foot buffer from the edge of the wetland. The applicant has proposed to decrease the buffer in some areas while increasing it in others. Also refer to Attachment 11. Wetland buffer averaging is allowed by ECDC 20.15B.080B. July 2, 2003 / Staff Report . f. • wilderness Bluff File No. S-2003-34 Page 5 of 8 c) The study from Landau also identifies Willow Creek on -site. It is a category 2 stream The required buffer area is far exceeded by the presence of the wetland, so it is not necessary to identify it. D. Wetland Buffer Averaging: Compliance with ECDC 20.15B.080B 1. The applicant has requested to modify the wetland buffer area —specifically decreasing it by 956 square feet and increasing it by 974 square feet. Averaging buffer widths may be authorized when the applicant demonstrates all of the following: a) Averaging is necessary to provide reasonable use of the property. Refer to ECDC 20.15B.040C1 to 6. b) The critical area contains variations in sensitivity due to existing physical characteristics and that reduction from standard buffer widths will occur only immediately next to the portion of the critical area determined to be least sensitive. c) Low intensity land uses will be located immediately next to areas where the buffer width is reduced, and that such low intensity land uses are guaranteed in perpetuity by covenant, deed restriction, easement, or other legally binding mechanism d) Width averaging will not adversely impact the critical area's functional values, e) The total areas contained within the buffer after averaging is no less than contained within the standard buffer prior to averaging. In no instance, except where a previously existing legal encumbrance exists, shall the buffer width be reduced to less than 50% of the standard buffer width required. f) When the buffer is reduced, a buffer enhancement plan using native vegetation and fencing where appropriate must be reviewed and submitted for the area of the remaining buffer. The purpose of the buffer enhancement plan is to improve the function of the buffer to provide adequate protection to the critical area. 2. Applicant's Responses: The Critical Areas Report completed by Landau Associates responds to the criteria. Refer to Attachment 11. 3. Staff Response: a) The property is zoned for single family residential, RS-6, minimum lot size 6,000 square feet. The applicant is only requesting to construct 4 single family residences on a property 77,106 square feet in size. Based on the underlying zoning the property could yield 12 lots. However, recognizing the constraints of the critical area, it is reasonable to allow development on the portion of the property not occupied by the wetland. The applicant is only requesting to reduce the buffer area no greater than 10 feet in width along the eastern edge to allow for adequate buildable area on lots 3 and 4. b) The site has been significantly disturbed by illegal dumping. Since the applicant will be required to remove the debris and re -vegetate in the disturbed areas, sensitivity is not an issue. c) Reduction of the standard 50-foot buffer width will only occur adjacent to single family residences. Single family residential is considered to be the least intensive land use. The applicant will be required to record the wetland and revised buffer as a critical areas easement. Refer to condition of approval #3. d) According to Landau Associates review, width averaging of the buffer will not adversely impact the critical area's functional values. July 2, 2003 / Staff Report Wilderness Bluff File No. S-2003-34 Page 6 of 8 e) The buffer averaging will result in a net increase of 18 square feet to the wetland buffer area. f) The applicant must comply with the recommended mitigation measures including fencing of the rear yards and revegetation of disturbed areas. g) Because. the standard buffer for a class 2 wetland is 50 feet. Buffers could be reduced to a minimum of 25 feet. In this case, it is only being reduced to 40 feet. 4. Conclusions. The buffer modification should be granted. E. Subdivision Review Criteria: Compliance with ECDC 20.75.085 1. Facts: ECDC Section 20.75.085 lists the following criteria to be used when reviewing a proposed subdivision: Environmental, Lot and Street Layout, Dedications, Improvements, and Flood Plain Management. 2. Staff Response: a) Environmental. Although the proposal includes removal of a small portion of the wetland buffer and equal part will be added to that buffer. The wetland will remain undisturbed. The lot placement is compatible with the existing topography. Each lot meets the dimensional requirements of ECDC 16.20.030. b) Lot and Street Layout. Each lot exceeds the minimum lot area of 6,000 square feet. Each lot contains an adequate buildable area. To minimize drainage issues, each lot must be connected to the city's storm water system. c) Dedications. Refer to Attachment 5. d) Improvements. Refer to the Engineering memorandum contained in Attachment 5. e) Flood Plain Manage, ment. The subject property does not fall into a flood plain zone. Therefore, this criterion is not applicable. F. Public Comments 1. Public Comments: Refer to Attachments 5, 6, 7, 8, 9, and 10. The concerns are summarized below. 2. Staff Response: a) Drainage. The applicant must comply with the requirements of ECDC Title 18. Refer to Attachment 4. The applicant is only responsible for the drainage that will be generated by the new development on site. The applicant is not responsible for accommodating drainage for neighboring development. b) Wetland Preservation. The wetland will remain undisturbed. Only a portion of the wetland buffer area will be modified. Refer to Attachment 11, which indicates the wetland buffer area that will be removed and the equivalent area that will be enhanced. c) Soil Stability. The applicant will be required to submit a soils report with each building permit application. d) Dumping. Over the years there has been significant illegal dumping on -site. As part of the subdivision the applicant will remove the debris, as encouraged by Landau Associates critical areas review. e) Ownership. The site is privately owned. Provided that the applicant complies with the Edmonds Community Development Code requirements, the City cannot deny the short July 2, 2003 / Staff Report • Wildemess Bluff File No. S-2003-34 Page 7 of 8 plat application. In addition, the City does not have the funds available to purchase the property. f) Wildlife. By preserving the wetland, the existing wildlife habitat can be maintained. g) Open Space. The wetland and associated buffer are occupies approximately 76%. The site is 1.77 acres in size, and the applicant is proposing that 1.35 acres remain undisturbed. h) Critical Areas Review. The critical areas review was conducted by an independent reviewer, Landau Associates. i) Subdivision Review. Review by the City of short plat applications is detailed in the Edmonds Community Development Code. The ECDC states that short plats be reviewed by a designated staff member. The City does not have a City Review Board to review, short plat applications. III. RECONSIDERATION AND APPEALS The following is a summary of the deadlines and procedures for filing reconsiderations and appeals. Any person wishing to file or respond to a recommendation or appeal should contact the Planning Department for further procedural information. A. Request for Reconsideration Section 20.95.050.B.2. provides for Staff to reconsider his/her decision or recommendation if a written request for reconsideration is filed by the applicant within fourteen (14) calendar days of the date of the initial decision. The reconsideration request must cite specific references to the findings and/or the criteria contained in the ordinances governing the type of application being reviewed. B. Appeals Section 20.105.010.A describes how appeals of a Staff decision shall be made. The appeal shall be made in writing, and shall include the decision being appealed along with the name of the project applicant and the date of the decision, the name and address of the individual or group appealing the decision, their interest in the matter, and reasons why the appellant believes the decision to be wrong. The appeal must be filed with the Development Services Director within fourteen (14) calendar days after the date of the decision being appealed. Appeals are presented to the Hearing Examiner. C. Timeframes The time limits for Reconsiderations and Appeals run concurrently. If a request for reconsideration is filed before the time limit for filing an appeal has expired, the time "clock" for filing an appeal is stopped until a decision on the reconsideration request is completed. Once the staff has issued their decision on the reconsideration request, the time clock for filing an appeal continues from the point it was stopped. For example, if a reconsideration request were filed on day 5 of the appeal period, an individual would have 9 more days in which to file an appeal after the staff issues their decision on the reconsideration request. July 2, 2003 / Staff Report ti • Wilderness Bluff File No. S-2003-34 Page 8 of 8 IV. LAPSE OF APPROVAL Section 20.075.100 states "A preliminary approval of a subdivision or lot line adjustment will expire and have no further validity at the end of five years, unless the applicant has obtained approval of the final plat or has filed an application to extend the time before the approval expires." V. NOTICE TO COUNTY ASSESSOR The property owner may as a result of the decision rendered by City Staff request a change in the valuation of the property by the Snohomish County Assessor's Office. VI. APPENDICES Attachments 1 through 11: 1. Vicinity / Zoning Map 2. Application 3. Plat Map , 4. Memorandum from the Engineering Division, dated 3/05/03 5. Letter from Louise Thorson 6. Letter from Robert & Sherian Marvin 7. Letter from Helene Spangler 8. Letter from M.C. Malin 9. Letter from Olof Strandell 10. Letter from Carol Hayes 11. Wetland Report by Landau Assoc. VII. PARTIES OF RECORD Brian & Dolores Buchea Alan Jackson Parks Division Engineering Division PO Box 1595 30277 Hwy 20 E Planning Division Public Works Division Ferdale, WA 98248 Republic, WA 99166 Fire Department Building Division Lisa Bride Louise Thorson Robert & Sherian Marvin Helene Spangler Suite 135 622 Elm PI 661 Birch St 606 Elm PI 4100 — 194`s St SW Edmonds, WA 98020 Edmonds, WA 98020 Edmonds, WA 98020 Lynnwood, WA 98036 M.C. Malin Olof Strandell Carol Hayes 1224 — 7's Ave S 626 Elm PI 709 Elm PI W Edmonds, WA 98026 Edmonds, WA 98020 Edmonds, WA 98020 July 2, 2003 / Staff Report Zoning and Vicinity Map 41 Attachment 1 File No. S-03-34 city of edmonds ,i 1 land use application 9 ARCHITECTURALDESIGNREVIEW A COMPREHENSIVE PLAN AMENDMENT 9 CONDITIONAL USE PERMIT 9 HOME OCCUPATION A FORMAL SUBDIVISION P SHORT SUBDIVISION 6 LOT LINE ADJUSTMENTlCa 0 PLANNED RESIDENTIAL DEVE PM 0 OFFICIAL STREET MAP AMENDMENT FILE # 5�� ZONE TLg- �D _— ATE &C— I Q -•O3 REC'D BY _ WEARING RECEIPT # a.1 q8a HEARING DATE 0 HE 6 STAFF 6 PB 8 ADB 9 CC —4ac-4 qe4pe, 9 STREET VACATION 9 REZONE ;> Ci C, or, c +o 6 SHORELINE PERMIT qo-"- 1� o 9 VARIANCE / REASONABLE USE EXCEPTION 6 OTHER: p�rrLt= PROPERTY ADDRESS OR LOCATION 1230 7TH AVE. S EDMONDS WA .98020 PROJECT NAME (IF APPLICABLE) WILDERNESS BLUFF PROPERTY OWNER BRIAN R DOLORES BUCHEA PHONE# 360-380-1353 ADDRESS P.O. BOX 1595, FERNDALE, WA 98248 E-MAIL ADDRESS FAX # TAXACCOUNT# 270325003011 SEC.25 TWp• 27 RNO 03 DESCRIPTION OF PROJECT OR PROPOSED USE FOUR (4) LOT SUBDIVISION APPLICANT ALAN R. JACKSON PHONE# 425-750-0854 ADDRESS 30277 HWY 20 E, REPUBLIC, WA 99166 E-MAIL ADDRESS Fax # CONTACT PERSON/AGENT L I S A BRIDE ADDRESS 00-194TH Sn,. SW, SUITE 135,LYNNWOOD, WA 980365-339-7432 E-MAILADDRESS ligabride@cbba.com FAX# 425-672-9182 The undersigned applicant, and his/her/its heirs, and assigns, in consideration on the agrees to release, indemnify, defend and hold the City of Edmonds processing of the application reasonable attomey's fees, arising from any action or infractions harmllee8s from � y and all damages, including inaccurate or incomplete information furnished action the a part upon false, misleading, BY my signature, I certify that the info^ - -- - PIeant, his/her/its agents or employees. knowledge and that I am authorized to , SIGNATURE OF APPLICANT/AGENT Property Owner's Authorization Tewith submitted are true and correct to the best of my the behalf of the owner as listed below. DATE �� 16 By my signature, I certify that I have authorized the above Applicant/Agent for the application, and grant pe s 'on ,, a public officials and the stafff the apply of Edmonds to enter the subject Property for the purp es o 'spa ion•'a d os ' subject land use P g attendant to this a icat' n. J SIGNATURE OF O i DATE - O This application form was revised on 1/27/00. To verify whether it is stillcurrent, call (425) 771-11") LU ®RARI LANNIN( 01- & HwWOUts\P+blic Handout$ and Use Applicadon.doe L S-2003-34 Attachment 2 N.W.1/4, S.W.1/4, SECTION 25, TOWNSHIP 27 NORTH, RANGE 3. EAST, Wm — RECEIVED FEB 19 2003 - PERMIT COUNTER . vr'cirotyMap GRAM4rcSCAL • 0 0 rs ao 60 (nit FEEr) ! im* a 30 ft. Legal Dtscr;pt* . aras►aw.Rt►warwravwwawww wewewwar ewwar wane► w wr awwim awwa w m x wwwr ar O@r= �O wwwwalwanwewwwwamw MAWW�mmm RAuumm awre wrmwrwamwm =W ar wwwww Bass Of BCN7i/� wr w Q war -- Project DaM: AMMSwAwt nQ L. (Y.Aej Q IMQ Mb Da�wwal am w a A e AND am awr[ wwrA� iws®waQwaa a� y-saws waRr euwwgswwwaww .FNew sa aawwwawr sdw waw Ra! 44W Owner: ApplicapW mwawerao w,w+amr m"m mm w w!1 ra a -- w�ww► d Qwi = xm. rK rrrlcATE: 1-9 N.)� °"' AM A.F.M. INDUSTRIES, INC. Preliminary Short Plat Map 00 JarJdw- ~ 3 W d Bowe Y Af s�ava c for Alan Jackson 13Yarett, VA 08203 ' ........... rat: 426.869.8960 aR�wri M.R.P. atE. o1/"/os .roe MO. scuc Fez- 426.968.6869 2=-am r _a emast asa® Br: su ry une Rao ww. s cr/ar.• �,,) aaw. Jr. wsx wa. arc. Af11 - 38 �/� 61, CITY OF EDMONDS'�° ENGINEERING REQUIREMENTS FOR PLATS AND SUBDIVISIONS/. Name:.. Buchea File No.: S-03-34 Approved by. .f 4 i Vicinity: 1230 7t° Ave 5 QZ50 r.— -:.... Dm­ WA --nor rintP a as ,�'r Re4`d pno>c rat lteg'd w/bldg. Peniiit )fond posted .5 Cori> ete K zr ��94^�{ to recordm Su Rights-qf-way fbr.pubhg streets . _ X ;basements (City utiliO private access, other utilities); Provide easements as needed. X Street improvements .(ACP with curb and gutter): . Each -Jot shall have an individual access to 7'h Ave S. X X 4::Street turnaroUq4ti All lots shall have an on -site turn around X 5, SideAv�lks and/or vyalkway`s: _ Construct five -foot -wide concrete sidewalk to City standards X along the entire property frontage. 6,' Street lights. . N/A X Planting strw :.: ... . N/A X 8 :Watei system improvements (pipelines; fire hydrants; pump . stations�.telemeterin D.S.H;S. etc, :_ Provide service to each lot. X Connect to public waters stem X 9. Sanitar*:sewersysiem'iinprovements (pipelines, pump Stations telemeterin health districtetc'.): Provide new service to each lot X Connect to public sewers stem X 10. Sto. sewer system mprovenients:(pipelines, pump Stations DOE;.fisheries etc. Provide storm sewer service to all proposed lots. X Construct storm detention system sized to provide adequate X capacity for all proposed impervious surface areas in accordance with ECDC 18.30. Any detained surface area that may be directed toward the X wetland area must go through water quality process Connect to Public Storm system x 11. On-site.drainage:(plan;pe Ord:3013)i. Connect all new im srvious surfaces to detentions stem. X X 12. Underground wiry (per.Ord..1387); Required for all new services X X 13. Excavation and adin :( er UBC, Chapter 70): Submit a grading plan as parl of engineered site plan. X X 14. Si a e(per City En ineer N/A X 15. Survey monumentation (per Ord., Section 12.10.120): N/A X S-2003-34 VAdvrw\sp\03-34buchea plt.doc Attachment 4 Req'd prior, Req'qw/b1d& Bond,`,71; et�.' 7 to recording Permit:.'., p. 16. As-buili City Engineer): Re . quire I for all uiilfty construction. x x 17. Oihe T.requirements i 18. Engin - fPF0!: q�;Mg ?4.,-. _ a) Drainage system design review at $50 per lot x b) Sewer connection charge/LID fees to be paid in full. x c) Drainage system inspection fee at $50 per inspection. x d) Plat inspection fee: 2.2% of improvement costs x e) Plan review fee: $250. x IWO ENGINEERING PROGRAM MANAGER, CITY OF EDMONDS DATE The Engineering reqyjrqMpnts have been coTplered and the subdivision can be recorded Authorized for recording by: Date: VAdvrW\5p\03-34buchea pit-doc June 5, 2003 City of Edmonds Development Services Department 121 5`b Avenue N. Edmonds, WA 98020 Re: Notice of Development Application dated 5/15/03 File #S-03-34 Applicant,. Alan Jackson Project Location: 1230 7'b Avenue S. Edmonds, WA Attention: Stephen F. Bullock Tlns.letterris to cover- the City ofFdmonds' Land -Ilse -Complaint en-e€whietrl . May 30,2005-andwakdated lx:;. :::, 4:OLTTR- `. ad completed this Complaint Form, (of which 1 was told was not the correct form) in response to the Notice of Development Application dated 5/15/03. The contents of this complaint form was written as follows: 1230 7'b Avenue S., Edmonds, WA. This land/hill where the four homes are to be built is not solid land. It has grown from years of dumping debris. Two vehicles have had to be towed from this area after unloading their trash. We are still recovering from our loss due to the three subdivisions that have been built around our property. If the water table is disturbed again and our home is flooded, we will hold this contractor/builder, Alan Jackson and the City of Edmonds responsible. It would be good if the City of Edmonds would purchase this property and let it be a sanctuary for the small critters that remain Attachment Robert & Sherian Marvin May 30, 2003 Respectfully, . �Zianarv�661 -F ( S-2003-34 Attachment 6 30) ZOO vx VI MAY 3; . 2003 ,� ELOPMENT SERVICES !1 (�N\ uTY � �^-� �-��4..f Jl Q,vVi a CCYi CPJI t2Q� (�W �iu� Cl�bc�viS�iveC�vn � r�vS�1 ,Xa�ua.c- a6j� IZ3 0 A 17��,5°n +D akc� � -Y►� la.�-� a.�' 4oJ czdo2vcg s � c� 5\'- �9 l�.�c �Qv tacP1 ehd""d 50" ""v 16�n J 1 'u� � 8�✓�'`�t Arm vnc � �X 2wl 1 'ff-.t lznov-W � �C (�vn�eI "fin `,`P ri (LSs Aaq- 0 ov-Cuase ar►a yvlo-d &f �rl-fin, Xvl(lpt� DLZYYLF)l /' S-2003-34 a,{ �� ��"�' /`Y (�G�=�fiS. �yl aryl �-y�0S� Attachmenti 2.1�.� -I'G 6 eel.- ja e6 bqaace Crree' a. � o� �s�► w � l i b� d,�s �° � � �. �� �-s �v�z. �-�1w� �-QI ✓fi w e- ( U ,J l y � C vans 4(11 e.-Ir I I S P o c C a-S L9 Yl d cz %fir 15 Y2 o 4�' cv w� Id an , ( fez+ is ( � Q b c� (ec ec� 1 v o- -c e-f lol .ld Ii F j no f PID)s®vi y ovn cm�cei- ais a -I'� e a 1 d L � y Q oC �Gta.� i ' vww a a ve cc e_4' � v clam o I IV live, `�v live 1''`, 4\1"'r Af ('l o ws-e � �6r �w (f w 1 `�1 d m eve �5 b P�ca�-� s '� Yft7 Co"L, Cu K5 i-ef la_�S rn 'In -� r) ) -�D. o 3 S m CLF'e I`1 C1 lelen e Z, 5� 7 : 7- ,, le41 6 061P &Z- `x P2-A6c bJ,176NDS �.�A 9�a� D This site has been designated as a critical area, CA-97-59. There was a good reason for that. The top one-third is steep bank and the bottom two-thirds is marsh land that is the source of Willow Creek; the only water supply to the Deer Creek Salmon Hatchery. This site had been for sale, for decades. In all those years no builder could find a way to build houses on this site, and for good reason. The entire area here is a large seepage area fed by the huge rain basin area around Chase Lake. The many spring in this area of the bowl flow year round, undiminished and many expensive problems have been caused to homeowners because the City has issued building permits without taking ground water sources into consideration. There are at least seven houses very close to this site that have had to retrofit drainage corrections that have cost homeowners from one to fifty thousand dollars. In my view, the city should be held responsible for errors. It is the City that should maintain the body of knokledge of land and water conditions within its boundaries. It is the City, upon whom the builders rely to issue viable building permits. It is the City who draws up the regulations pertaining to development, and it must be the City who rejects unsuitable sites for the protection of the builders and the future homeowners. This site, CA-97-59•, falls in the category of, Unsuitable For Development. RECOVED Ra ryl _ MAY 3 0 2003 DEVELOPMENT SERVICES me 7rj� �J s G S-2003-34 Attachment 8 of E• Attachment to Cit y Edmonds Land Use Complaint Form 27-03 Subject: Notice of Development Application; May 15, 2003, File #S-03-34 ttvr?e> Details of Complaint: This Complaint is filed because of my concerns that the City of Edmonds follow city codes and regulations, as well as those of state and federal agencies, and will not repeat earlier mistakes when considering the approval or rejection of the subject permit application. 1230 7"' Ave S appears utterly unsuitable for the intended subdivision and home construction. The proposed development is in conflict with city and environmental codes. The lot forms a deep ravine with very steep sides (a Critical Area with Erosion Potential), sloping down into a small creek that eventually feeds the Deer Creek Salmon Hatchery. As amply demonstrated by the recent construction at 729 Elm Place W, it is highly likely that any soil removal or disturbance will expose presently unknown., subsurface springs and water strata. This has become a major problem for homeowners in this area causing costly repairs and no doubt exposing the issuer of the building permits to potentially devastating lawsuits. The likelihood that the wetlands on 1230 7t' Ave will be ruined or seriously damaged by this construction project through soil erosion and other negative impacts cannot be ignored. In addition, as encountered during the construction of 729 Elm Place, it is to be expected that silt, mud and suspended concrete dust will be carried into Willows Creek, a designated fish carrying stream. During the 729 Elm Place project Willows Creek was often filled with mud and silt, depositing a thick layer in the creek bed. No fish would have survived in that environment. After city approved changes at 729 Elm Place, the water from the springs is now dumped into a new and certainly not inexpensive city storm sewer. The flow in the creek itself has been reduced to a trickle. The creek is no longer the living stream it used to be, taking away from the rights of the lot owners. This presents another opening for legal challenge against the city. I contend that the City of Edmonds utterly failed to investigate these problems before issuing the building permit, and to monitor and control the construction. It inflicted irreparable harm to the creek and left the future owner of 729 Elm Place with a major, never ending problem. The purpose of this Complaint is to prevent a repeat of this debacle. . The proposed development at 1230 7"' Ave S will impact an environmentally still much more sensitive area. I believe the City cannot afford not to request input from state and federal environmental and wildlife agencies before any decision is made to proceed with this development. With this notice I request that: 1. The City of Edmonds require the Applicant to present a review of the impact of the proposed project on the environment, prepared by an independent, recognized authority and demonstrating no adverse effects to the steep slopes, to area fish and wildlife, to the wetlands and creek, to existing homeowners, and to the salmon hatchery. 2. The City Review Board positively and irrefutably establish that the proposed development meets, or does not meet, as the case may be, any and all applicable city, county, state and federal codes and regulations, and make available to the public a detailed and unabbreviated record of its deliberations. S-2003-34 Attachment 9 • ==- Signatures.�: .. ... ...... .. Name (please print): �� ��// Phone:..itl Address: 77 -,1... _ _ RECEIVED ul_1' DEVELOPMENT SERVICES S-2003-34 Attachment 10 /�� /l�i�l`Q�'�'%• /�SD�" ��2CeS¢ .SOU-2!� /lOh9-d-ct' �. Oj art &/,Ov a-n o m�r�-e. w a-9�eL �� � � � ,o t-a Gl �. s. �%1•�. 14s- 7L Cam �f�r/�P `7�k8/li � A( &005: wga44eA �d' cv jrta_g C42-0-e-�ivQ'G Gz! r�ec-I�e C/ t 4 .-yr G�l kccwr i_ a- o `�• � a�'Q..s �-1-�-cam � Q� �� VO LG ,o'­ Name (please print):-( ��17L�q��--C Phone: Address: Critical Areas Report 1230 7th Avenue South Edmonds, Washington May 8, 2003 Prepared for City of Edmonds Development Services Department 121 5th Avenue North Edmonds, Washington 98020 14 LANDAU ASSOCIATES 130 2nd Avenue South Edmonds, WA 98020 (425) 778-0907 S-2003-34 Attachment 11 I TABLE OF CONTENTS 1 1.0 INTRODUCTION 1.1 SITE LOCATION AND DESCRIPTION 2.0 METHODOLOGY I3.0 RESULTS 3.1 DOCUMENT REVIEW 3.2 FIELD DELINEATION RESULTS l 3.2.1 Critical Areas Habitat ` 3.2.2 Upland Habitat 3.3 CRITICAL AREAS CLASSIFICATION AND BUFFERS 4.0 MITIGATING MEASURES 5.0 USE OF THIS REPORT 6.0 REFERENCES APPENDICES A Wetland Delineation Methodology B Wetland Data Sheets LIST OF FIGURES FiLure Title 1 Vicinity Map 2 Wetland Flagging Map Page 1-1 1-1 2-1 3-1 3-1 3-1 3-1 3-3 3-3 4-1 5-1 6-1 05MM3 UEDNINAMPROCIOMI IO%TrH AVE CRITICAL AREAS RPT.DOC H LANDAU AssociATEs IY 1.0 INTRODUCTION Landau Associates wetland biologists conducted a critical areas study, consisting of a wetland delineation and stream assessment, on the approximately 1.78-acre property at 1230 71h Avenue South located in Edmonds, Washington on February 12, 2003 (Figure 1). The scope of services for this project included: • Review of public domain information available for this site, including the Snohomish County area soil survey (Debose and Klungland 1983) and the City of Edmonds (City) Critical Areas Determinations (dated April 25, 1997 and June 20, 2001) for this site • Conduct a critical areas site investigation including the field delineation of onsite wetlands and flagging the onsite reach of Willow Creek • Prepare a Critical Areas Report documenting the findings of the site visit, including a brief summary of the methodology used, wetland habitat present onsite, classification and buffer determination for onsite wetlands and Willow Creek, mitigating measures appropriate to preserve onsite critical areas, and copies of supporting documents and figures (field data sheets, site map, and critical area survey map). 1.1 SITE LOCATION AND DESCRIPTION This approximately 1.78-acre property is undeveloped and is bound by 7`s Avenue South on the east side, houses and maintained lawn associated with the Elm Place development on the north and west sides, and single family residences on Paradise Lane on the south side. The easternmost portion of the site, in the 70'Avenue South right-of-way, is fairly level and is comprised of mowed grasses and forbs. The property slopes down steeply to the west of the right-of-way to approximately the mid -portion of the site. This area is comprised of forested and shrub habitat. The entire western half of the site's gently undulating topography is relatively flat and is comprised entirely of forested wetland. In addition, the south tributary to Willow Creek flows along the western edge of the site. Willow Creek is the only water supply for the Deer Creek Hatchery (City of Edmonds 1990). This site has been used for dumping of landscaping waste and other refuse, such as lumber, carpeting, building materials, etc. Most of the dumping has occurred on the southern half of the site and extends approximately halfway down the slope. A smaller dumping area, composed entirely of landscaping waste, occurs at the south-central portion of the site, directly behind Lot 17 (a residence on Paradise Lane). 05MM3 11EDMNASIWPROC107411 IMM AVE CRMAL AREAS RPT.DOC 1-1 L ANDAu AssoclAT£s 2.0 METHODOLOGY Landau Associates biologists Diane Brewster and Rone Brewer conducted the critical areas field investigation on March 5, 2003. Wetlands were delineated using the 1987 U.S. Army Corps of Engineers (USACE) Wetland Delineation Manual (USACE 1987), and supplemented with the USACE Regional Guidance letter on the 1987 Manual (USACE 1994). The routine determination was used because the onsite wetland area has a homogeneous vegetation, soil, and hydrologic regime. Appendix A provides a complete description of the methodology used in this investigation. Public domain resources were reviewed prior to the site visit to determine existing conditions and potential wetland indicators on the site. During the site visit, the project site was walked to identify plant community types and identify wetland habitat. Three representative sample plots were selected within wetland and adjacent upland areas to define the wetland habitat and its extent. Each sample plot was marked with pink flagging and labeled TP-I, TP-2, etc. Data on vegetation, soil, and hydrology were collected at each point and recorded on the 1987 routine wetland investigation data form. Appendix B provides the data sheets completed for this project. The wetland edge was determined where the following three parameters were met: 1) the dominant plant species were considered hydrophytic by the U.S. Fish and Wildlife Service (USFWS) (Reed 1988); 2) soil was considered hydric under federal definition; and 3) hydrologic conditions meeting the federal wetland definitions were present or inferred. The wetland boundaries were marked in the field with pink flagging printed with the words "Wetland Boundary." To distinguish these flags from wetland flagging placed in July 2002 by a different firm, each of our flags was marked with the letters "LA" and then numbered sequentially. The stream- course was also marked using pink flagging labeled LA-S 1, LA-S 12, etc. These flags were not surveyed for reasons discussed in the field delineation results section of this report. The original wetland survey map (B&A Inc. 2002) is accepted for the purpose of this.Critical Areas Report (Figure 2). OWS/03 11EDMNASMPR00074\1107TH AVE CRITICAL AREAS RPT.DOC 2-1 LANDAU ASSOCIATES • • 3.0 RESULTS 3.1 DOCUMENT REVIEW Both the Snohomish County area soil survey (Debose and klungland 1983) and the City's Critical Areas Determinations (City of Edmonds 2001; City of Edmonds 1997) indicated the presence of wetland habitat and a creek onsite. One soil type, Everett gravelly sandy loam, 15 to 25 percent (map unit 19), is mapped on the entire site (Debose and Klungland 1983). The Everett series consists of very deep, somewhat excessively drained soils on terraces and outwash plains, and formed in glacial outwash. A typical profile includes a layer of very dark brown (IOYR 2/2) (Appendix A), very gravelly sandy loam to a depth of 6 inches below ground surface (BGS). Below this, to a depth of 18 inches, this soil is a dark brown (7.5YR 3/4) very gravelly sandy loam. Everett gravelly sandy loam is not identified as hydric (or wetland) soil, nor does it have hydric inclusions (USDA 1988). However, one of its inclusions, Alderwood, does have Norma loam (a hydric soil) as an inclusion. Both the April 25, 1997 and the June 20, 2001 • Critical Areas Determinations completed by the City identified wetland habitat and Willow Creek as occurring on this site. The City gives Willow Creek a rating of Class 2 stream, requiring a 25-ft buffer (measured from the top of the bank) and a 15-ft building setback. 3.2 FIELD DELINEATION RESULTS The weather during the March 5, 2003. site visit was cool (ranging from approximately 40 to 507) with scattered showers. According to the National Oceanic and Atmospheric Administration, the water year to -date precipitation was slightly below normal for the Puget lowlands of western Washington. It had rained heavily on March 2, 2003. 3.2.1 CRITICAL AREAS HABITAT We identified one wetland and one creek on this site. The majority of the observed wetland habitat was located in the western half of the site with the wetland edge located between 206 ft and 216 ft in elevation. In addition, an area meeting the soils, vegetation, and hydrology parameters was observed near the southern end of the site where the wetland extends east up the slope to the edge of the large dumping area at approximately 236 ft in elevation. This upslope area has the same soils and vegetation community as found on adjacent upland portions of the slope. The deciding factor to classify this area as wetland was the presence of groundwater within 12 inches of the soil surface. However, the groundwater 05/08/03 11EDMNAMPROC1070111017TH AVE CRITICAL AREAS RPT.DOC 3-1 LANDAU AssocIATE$ pattern had a distinctive V-shape (appearing farther upslope at one location only). A later investigation and site visit on April 18, 2003 determined the water source to be outflow from drain tiles that collect water from the east side of Vh Avenue and deliver water to the project site as point source approximately 6 inches below the surface. The upland portions of the project site adjacent to this area are considered to be the natural conditions where groundwater travels downslope from the east side of Vb Avenue at a depth below 12 inches from the surface. Because the hydrology at the one upslope area is due to an artificial point source that discharges groundwater close to the soil surface, this area is not considered as wetland and the wetland edge is considered to be the original boundary (as delineated by B&A Inc. 2002) near the. toe of the slope where water seeps into the wetland at a relatively constant topographic elevation across the site. The onsite wetland is part of a larger wetland system adjacent to Willow Creek that extends offsite to the west and north. However, the offsite wetland habitat has been disturbed by adjacent developments and consists primarily of maintained lawn rather than the native plant communities found on this site. A small area of upland was observed in the northwestemmost corner of the site, but was not flagged because its location excludes any development in this area. Willow Creek meanders through the wetland, flowing first to the north, then to the southwest. It enters the site via a culvert at the southwest boundary of the site. The culvert collects waters from what was the creek's original headwater area prior to development of this area. Willow Creek exits the site at the northwest boundary, joining the west fork of Willow Creek just outside the site boundaries, then flows to the Deer Creek Hatchery and eventually into Puget Sound. The wetland is composed of palustrine forested habitat and is dominated by red alder (Alnus rubra, FAC) with a few western red cedar (Thuja plicata, FAC) and western hemlock (Tsuga heterophylla, FAU-) scattered throughout. Numerous snags were observed throughout the wetland. The understory is dominated by patches of salmonberry (Rubus spectabilis, FAC+), with areas of vine maple (Acer circinatum, FAC-), Himalayan blackberry (Rubus armenicus, FAC-) and red huckleberry (Vaccinium parifolium, FACU) on hummocks along the edges. The sparsely vegetated ground layer is dominated by patches of skunk cabbage (Lysitchitum americanum, OBL) and piggyback -plant (Tolmiea menziesii, FAC). Other groundlayer species observed in the wetland include lady fern (Athyrium felix- femina, FAC), deer fern (Blechnum spicant, FAC+), stinging nettle (Urtica dioica, FAC+), and patches of slough sedge (Carex obnutpa, OBL) and bittersweet nightshade (Solanum dulcamara, FAC+). Vegetation observed throughout the wetland meets the definition of hydrophytic (wetland or water - loving) vegetation. 05/08/03 IXEDMNAMPROC1074111WTH AVE CRITICAL AREAS RPT.DOC 3-2 LANDAU AssociATEs Soil observed in the wetlan d is typical of Norma soil and consists of a black (lOYR 2/1) silt loam to a depth of 11 inches BGS. Below 11 inches, soils are a dark gray (10YR 4/1), gravelly sandy loam. This soil meets the definition of hydric soil. The wetland is located within the Willow Creek flood plain. Soils in this area are saturated to the surface and small areas of pooled water up to 1 inch were observed. Based on a visual evaluation, groundwater flows downgradient from the eastern portion of the site into the wetland and Willow Creek. Wetland hydrology indicators include adventitious roots on the trees located within the wetland, water - stained leaves, saturated soils, and areas of standing water. Based on these characteristics, this area meets the criteria for wetland hydrology. 3.2.2 UPLAND HABITAT Upland habitat is comprised of both forested and shrub habitat. The shrub habitat is dominated L� by nearly monotypic stands of Himalayan blackberry.. The forested habitat has widely spaced trees consisting of red alder, big leaf maple (Acer macrophyllum, FACU), western red cedar, and holly (Rex aquifolia, FACU). The understory is dominated by salmonberry with areas of Indian plum (Oemlaria cerisformis, FACU), black raspberry (Rubus leucodermis, NI) and an ornamental shrub identified as laurel. The ground layer is composed of patches of stinging nettle and sword fern (Polystichum munitum, FACU). Soils.are similar in color and texture to those observed in the wetland; however, no groundwater 1 was encountered to 18 inches BGS. Thus, the upland area does not meet the vegetation or hydrologic parameters for wetland habitat. J 3.3 CRITICAL AREAS CLASSIFICATION AND BUFFERS The onsite wetland meets the City of Edmonds definition for a Class 2 Wetland because it is greater than 1 acre in size, is comprised of one habitat type (forested) without an open water component, and does not support species listed as threatened or endangered. Class 2 wetlands are typically given 50-ft buffers with a 15-ft building setback from the edge of the buffer. Willow Creek meets the City's definition for a Category 2 Stream because its flow is less than 20 cubic ft per second and its waters are used by salmon (offsite) at the Deer Creek Hatchery. Category 2 streams are typically given a 50-ft buffer by the City with the same building setback as described for wetland buffers. Because of the position of Willow Creek on this site, the creek and its buffer are contained within the onsite wetland and its buffer. 0SM8103 11EDMNAMPRO0074111017TH AVE CRITICAL AREAS_RPT.DOC 3-3 LANDAU ASSOCIATES v 4.0 MITIGATING MEASURES 1 The site design plan, dated February 11, 2003, has been reviewed in consideration of mitigating measures appropriate to preserving and protecting the onsite wetland and stream. The elements of the site Idesign that affect the onsite critical areas or hydrology into these areas include: 1. Building four residences along the east side of the site 2. Averaging the wetland buffer by adding buffer width at the north end of the site and reducing the buffer width at the south end while keeping the total pre -averaging buffer acreage 3. Tightlining runoff from driveways into the existing sewer system 4. Collecting roof runoff and dispersing it into infiltration/dispersion trenches at the back of each property 5. Installing ejector pumps in the basement of each home to be tightlined into the sewer system. ' In light of these proposed elements, recommended mitigating measures are given below: 1. Place 6-ft-tall wooden fences along the back boundary of each yard to ensure that people do ' not start to encroach into the buffer or throw yard waste into the buffer. 2. Clear all previously dumped materials from the site. ' 3. Returning roof runoff to the drainage basin via the proposed infiltration/dispersion trenches is recommended in order to ensure that the hydrology of the Willow Creek drainage basin is maintained. This element is recommended if further study finds that slope stability will not be adversely affected by this shallow groundwater and surface runoff. Infiltration rates for the trenches would need to match the stormwater runoff rates for storm events up to the 100- year storm. ' 4. Rather than tightline water from the ejector pumps to the sewer system, this water could be diverted into the infiltration/dispersion trenches to allow current groundwater flows to be I maintained into the Willow Creek drainage basin. This measure is recommended only if this additional runoff would not adversely affect the infiltration and runoff rate calculations described in item 4. 5. The outfall of the existing drain tile (encountered on the April 18, 2003 site visit) should be incorporated into the infiltration/dispersion trench to spread water flow across the area and reduce point source erosion. Again, this measure would only be feasible if it did not adversely affect the infiltration and runoff rate calculations described in item 4. Buffer areas that were cleared by large equipment during preliminary site studies should be revegetated with native shrub and tree species that occur on the site in the same densities that occur in undisturbed buffer areas. This will help to stabilize the slope. In addition, restoration of dense vegetation will serve to protect the wetland and stream from human intrusion. 05/08/03 %%EDMNASIWPROC%074t110VTH AVE CRITICAL AREAS RPT.DOC 4-1 LANDAu ASSOCIATES • • 7. The proposed buffer averaging will reduce the buffer near the south end of the site by a maximum of 5 ft. This is not expected to adversely affect the wetland and stream as long as a fence is installed. r OW8103 11EDMNASIWPROC1074117017TH AVE CRITICAL AREAS RPT.DOC 4-2 LANDAU ASSOCIATES A I L� 5.0 USE OF THIS REPORT • This report was prepared for the exclusive use of the City of Edmonds and their consultants for the specific application to this project. The use by others, or for purposes other than intended, is at the user's sole risk. The findings presented herein are based on our understanding of the Jackson Short Plat project, the City's Critical Areas Regulations, and on vegetative, soil, and hydrology conditions observed during site visits on March 5 and April 18, 2003. Within the limitations of scope, schedule, and budget, the findings presented in this report were prepared in accordance with generally accepted sensitive area investigation principles and practices in this locality at the time the report was prepared. We make no other warranty, either express or implied. Wetland areas delineated by Landau Associates are considered preliminary until the USACE and/ or local jurisdictional agencies validate the wetland boundaries. Since wetlands are dynamic communities, wetland boundaries change over time. The USACE typically recognizes wetland delineations for a period of 5 years. LANDAU ASSOCIATES, INC. Diane Brewster Senior Wetlands Ecologist Samuel Casne Director, Natural Resources DLB/SRC/ccy UM8103 1%EDMNAS%WPRC0074111017TH AVE CRITICAL AREAS RPT.ODC 5-1 LANDAU ASSOCIATES • 6.0 REFERENCES B & A Inc. 2002. City of Edmonds Critical Areas Study: Wilderness Bluff Planned Residential Development. Prepared for A.F.M. Industries, Inc. Gig Harbor, Washington. October. ' City of Edmonds. 2001. City of Edmonds Critical Areas Determination. Applicant: Brian & Doloris Buchea. Site Location: West of 7`s Avenue South between Elm Street and Birch Street (1.78-acre site). Determination No.: CA-97-59. June 20. . Ci ty of Edmonds. 1997. City of Edmonds Critical Areas Determination. Applicant: Brian &Doloris Buchea/Paul Sowa, John L. Scott Realty. Site Location: West of 7 h Avenue South between Elm Street ' and Birch Street (1.78-acre site). Determination No.: CA-97-59. April 25. City of Edmonds. 1990. Where in the World is Your Watershed: A Guide to Edmonds' Watershed Protection (pamphlet). City of Edmonds Public Works Department, Park & Recreation Department, and Engineering Division. Edmonds, Washington. 'Debose A. and M. Klun land. 19 3 g 8 Soil Survey of Snohomish County Area, Washington. U.S. Department of Agriculture, Soil Conservation Service, in cooperation with Washington State Department of Natural Resources and Washington State University Agriculture Research Center. July. Reed; Jr., Porter B. 1988, revised 1993. National List of Plant Species That Occur in Wetlands: Northwest (Region 9). U.S. Fish and Wildlife Service Biological Report 88 (26.9). Washington, DC. USACE. 2002. Special Public Notice: Final Regional Conditions, 401 Water Quality Certification I Conditions, Coastal Zone Management ConsistencyResponses, or Nationwide Permits p , i is for the Seattle District Corps of Engineers for the State of Washington. U.S. Army Corps of Engineers Regulatory Branch. Seattle, Washington. USACE. 1994. Washington Regional Guidance on the 1987 Wetland Delineation Manual. U.S. Army Corps of Engineers, Seattle District Regulatory Branch. Seattle, Washington. May 23. USACE. 1987. Corps of Engineers Wetlands Delineation Manual Technical Report. Y-87-1. U.S. Army Corps of Engineers, Waterways Experiment Station. Vicksburg, Mississippi. USDA. 1988. Hydric Soils of the State of Washington Conservation Service. October. U.S. Department of Agriculture, Soil 05/08/03 11EDMNAS%WPR0C10741110%7TH AVE CRITICAL AREAS RPT.DOC 6-1 LANDAU ASSOCIATES 361 !Sf 1063 1 745 1DOD t062 t1oT • mo flfo FIR R 333 FIR PL ffos e S $ $ fie fin aso 612 1103 file ei0 Sw s o AS fill 1114 me gild file 111D tin tir1 11r0 fin 710 1121 ills 1124 �D 1 tiN 11120 33n1 1iN /D6 n 1123 f IN tif 1N Set 140 I13D '1137 1'so /let 1110 1126 If32 1133 tiN 1132 MIT am 1f10 list 1136 Ilse 373 tia Q�".] na rise tia frse traw 1rs6 air 6" fee 1152 ties Sep llOf ifla 769 fly 1741 113D WOOOS D CREEK u Rau- PROPERTY OWNED BY 64 2 6" FIX) fps Teo Ife tip •,-,,tt WILLOW CREEK CONDO 7/e 776 n0 760 6:J.V � 63 mf 1211 ES 6f / 62 me 12DO j.'pW 61 f a NAt A 713 t2f0 12V Dra D33 1220 1 Q07 12n ill 1214 10 t� i i 7I0 In 713 ND MS a17 12T0 7jiir:; Q /2a n: 724 QT "9 Hf a% 7" ae 7" E Ry 12" F07 N6 fie e22 TVs/m "u 1227 L• , .` fr2e 1237 1216 fin rl; 1224 f 1 1 12/ 222 1226 BIRCH PL 1221 [% 1230 /23f 7/6 /27D ern fra , D/1 K1 of ifi est f 1261 TR!.! /230 1240 2a0 710 2/7 lr>r ,235 Isar R� tom. ,.:. 7 112a0 _< _ i3 :. 12M fat 1239 1262 123D D Subject Property 1251 1250 11.# 817 36 1Nf 12" J 1291 = fate 1 230 7th Ave S" 12e7 1:ie 1256 y� E ,asp A. 697 s s sae rass 719 1350 707 ¢ y`r esf MIi L $ fam ay oaf / 701 l 7r0 70 611 1]TH WY 7w 722 72s n0 rae2e tar _ 9 Sao 1371 20 £r>.' no g 8 g i•S$ ns Its 1a00 en I � Rae t., 709 6q 7M 7 1 ei 1109 00 DW r •�rrgg!U,,' 3/0 NTH WY SW 611 aa0 1607 e20 1af0 9 NS 1413 sa6 ai s/D +afe e 1619 rows �► est 2 617 len towel NTH WY SW fare }} /osn lose aw rte ' fur sfi sas $36 724 )20 n7 t 10n7 foeW NTH WY sn K S-12 102s 10611 BN es 717 723 ax if •�->• 10605 10519 10431 W4 f1 Y, /4" y -eyy a• { j. 0 i f 7a `.-' « a 724 n6 1679 e07 Wt fair 710 .�•R w '`'.;tip <�rx �C��q, 6q t * rsa 2666 a > 502 we 3 s w LANDAU ASSOCIATES I Source: City of Edmonds 1230 7th Avenue South Edmonds, Washington Not to Scale Vicinity Map Figure 1 • 1 J urrwrrunv w /\ve weuana 1 I :w/an MUIZ U"Veal Areas Rep0d%F -dwg (A)'Figmg 2' S/ rAW N88°30'11'W ti ?9f B{ 1 - p•_.AL�//,y ♦ . ♦ . ♦ . ♦ +' �o-�TSJ�'- �' • • w -`. , [ r 1 is 1 ' \\'w FR 1 ' \' \ I ,Willow Creek' • _ w ♦ ti 1 OF or. SAN • .♦ • w . • a `....II• j 1 1 I I r /♦ j i i i; i Serf. UA ........... ...... \p w . w y .. • • '�, ; i �.tl ,1 ; i' .../:.' I� 1 I t / ; - / - .10•' I 25� N M `I• ♦ • ...� -t • w w . a. Ar; a ,. , \•-4.-..;; r ; 1 1 EDII 1 N 1 I q ' `4�G/�:L... ♦ • ; �;, .r. r. .r. `'A ; I ; ; 1 ; 1 �a� l r}A�I%L latn's ♦ yd' 1 I I 0 ♦ . ` ` a. . w ♦ ♦ 1` ' v t li l . ' ' \4 i ' ® ry n I I � ,i .: •�♦ .?_�a: r /' \/,\ ♦ +� � �� 1% // I 1 r 1 t ♦ 1 I. '�/� � 1 1 R f /ATER .w . .. ♦ ♦ •. • - • I ..' i 1 �,�4 II i i. Il! I ' 1 Sl4LINr w ♦ .. w • _ ♦ v)/1e1 1 1 ' /j1//1 I , ; ,i I : ♦ 29d i L ' 1 3 rr 9. +�" ♦ ` .. • • a. . . . . . • ♦ 1 /: i� I /�/i�i / r i i1 ! i 1 wl cr. C.O. tic .. � N88030'11'W I 290.8R -- . � . I 1 , 1 MHN -s� Source: AFM Industries 2003 0 50 100 1230 7th Avenue South ' Figure 14 LANDAU Scale in Feet Edmonds, Washington Wetland Flagging Map ASSOCIATES 0 • • I k" KLEINFELDER An employee owned company October 28, 2003 Kleinfelder Project Number: 36170 Ms. Jeannine Graf City of Edmonds 12.1 Fifth Avenue North Edmonds, WA 98020 Subject: Third -Party Geotechnical Review Wilderness Bluff Short Plat 1230 - 7th Avenue South Edmonds, Washington Dear Ms. Graf: 0CT 3 0 BUILDING DEPT. This letter presents Kleinfelder, Inc. (Kleinfelder's) responses to the October 24, 2003 letter prepared by Mr. Alan Jackson (site developer). Kleinfelder performed a third -party independent geotechnical review for this site. Kleinfelder's review comments are presented in our October 15, 2003 letter. Mr. Jackson's October 24, 2003 letter addresses Kleinfelder's review comments presented in our October 15, 2003 letter. Kleinfelder has no additional geotechnical issues associated with this site at this time. Please call us at (425) 562-4200 if you have any questions regarding this letter or other geotechnical issues with this site. Sincerely, KLEINFELDER, INC. James M. Schmidt Senior Geotechnical Engineer L K, James A. McElroy Manager, Geotechnical Engineering. 36170/SWL295.doc Copyright 2003 Kleinfelder, Inc. Page I of 1 K L E IN F E L D E R 2405 140th Avenue, NE, Suite A101, Bellevue, WA 98005 (425) 562-4200 (425) 562-4201 fax io k'% KLEINFELDER An employee owned company October 15, 2003 Kleinfelder Project Number: 36170 Ms. Jeannine Graf City of Edmonds 121 Fifth Avenue North Edmonds, Washington 98020 Subject: Third -Party Geotechnical Review Wilderness Bluff Short Plat 1230 — 7te Avenue South Edmonds, Washington Dear Ms. Graf: RECEIVED 01CT172 3 BUILDING DEPT. This letter presents Kleinfelder, Inc.'s (Kleinfelder's) third -party independent review comments regarding geotechnical aspects for the Proposed Wilderness Bluff Short Plat located at 1230 — 7th Avenue South in Edmonds, Washington. Kleinfelder's services were performed in accordance with The City of Edmonds Task Order Number 2, dated September 26, 2003. SITE DESCRIPTION The short plat will consist of dividing an approximately 1.8-acre site into four lots and constructing one single-family residence on each lot. The site is bounded by 7 h Avenue South to the east, residential homes and lawn space to the north and west, and single-family residences to the south. The east portion of the site is fairly level and consists of mowed grass and forbs. The middle portion of the site slopes down steeply (up to 30 percent) to the west. Vegetation in the middle portion of the site consists of deciduous and conifer trees and shrubs. The west portion of the site is relatively flat and comprises a forested wetland. Willow Creek flows along the west edge of the site. The local neighbors have reported that up to approximately 10 feet of yard waste and construction debris has been dumped along the southern half of the site and extends approximately halfway down the steeply sloping portion of the site. Vehicles dumping yard waste and construction debris have become stuck and required assistance for removal. The neighbors have also reported that historic construction in this area has exposed springs within the slope. 36170/SEA3L280.doc Page 1 of 4 Copyright 2003 Kleinfelder, Inc. K L E 1 N F E L D E R 2405 140th Avenue, NE, Suite A101, Bellevue, WA 98005 (425) 562-4200 (425) 562-4201 fax k'% KLEINFELDER An employee owned company October 15, 2003 Kleinfelder Project Number: 36170 Ms. Jeannine Graf City of Edmonds 121 Fifth Avenue North Edmonds, Washington 98020 Subject: Third -Party Geotechnical Review Wilderness Bluff Short Plat 1230 — 7te Avenue South Edmonds, Washington Dear Ms. Graf: RECEIVED 01CT172 3 BUILDING DEPT. This letter presents Kleinfelder, Inc.'s (Kleinfelder's) third -party independent review comments regarding geotechnical aspects for the Proposed Wilderness Bluff Short Plat located at 1230 — 7th Avenue South in Edmonds, Washington. Kleinfelder's services were performed in accordance with The City of Edmonds Task Order Number 2, dated September 26, 2003. SITE DESCRIPTION The short plat will consist of dividing an approximately 1.8-acre site into four lots and constructing one single-family residence on each lot. The site is bounded by 7 h Avenue South to the east, residential homes and lawn space to the north and west, and single-family residences to the south. The east portion of the site is fairly level and consists of mowed grass and forbs. The middle portion of the site slopes down steeply (up to 30 percent) to the west. Vegetation in the middle portion of the site consists of deciduous and conifer trees and shrubs. The west portion of the site is relatively flat and comprises a forested wetland. Willow Creek flows along the west edge of the site. The local neighbors have reported that up to approximately 10 feet of yard waste and construction debris has been dumped along the southern half of the site and extends approximately halfway down the steeply sloping portion of the site. Vehicles dumping yard waste and construction debris have become stuck and required assistance for removal. The neighbors have also reported that historic construction in this area has exposed springs within the slope. 36170/SEA3L280.doc Page 1 of 4 Copyright 2003 Kleinfelder, Inc. K L E 1 N F E L D E R 2405 140th Avenue, NE, Suite A101, Bellevue, WA 98005 (425) 562-4200 (425) 562-4201 fax i k4 KLEINFELDER PROJECT DESCRIPTION One single-family residence will be located only on the easternmost quarter of each lot, while the larger remaining portion will be a critical areas tract. Each home will consist of one floor of living space and a garage over a daylight basement. The homes will also be set back approximately 25 feet from 7t' Avenue South. Cuts and fills on the order of 8 to 10 feet will be required to achieve the proposed finish floor elevation. Some filling in the home backyards will be necessary to create a lawn area. PURPOSE AND SCOPE The purpose of our geotechnical engineering services was to provide third -party, independent review of available geotechnical documents for. the site and preparation of this report. THIRD -PARTY INDEPENDENT REVIEW Our third -party review consisted of reviewing the following documents that were provided by the City of Edmonds: • Five letters of complaint from local neighbors. • Critical Areas Report 1230 7th Avenue South, Edmonds, Washington, prepared by Landau Associates for the City of Edmonds, Dated May -8, 2003. • Geotechnical Engineering Study, Proposed Wilderness Bluff Short Plat, 1230 — 7t' Avenue South, Edmonds, Washington, prepared by Geotech Consultants, Inc. for Alan Jackson, dated September 3, 2003. • Letter of Interest, prepared by the City of Edmonds to Mr. Alan Jackson. SUBSURFACE CONDITIONS Soil Geotech Consultants, Inc. (Geotech) explored subsurface conditions at the site by excavating seven backhoe test pits in August 2003. The test pits were located in the east portion of the* site where the residential homes will be located and extended to a maximum depth of about 9 feet below ground surface. Subsurface conditions encountered by Geotech consist of up to 24 inches of topsoil overlying up to 3 feet of weathered sand and gravel with abundant roots. This layer overlies dense to very dense sand and gravel with cobbles. Up to 2 feet of fill was encountered in three test pits. Geotech stated that large amounts of yard waste, garbage, and construction debris were observed scattered throughout the site and were encountered in the topsoil and fill. The site soils are classified as "Everett Series" according to the Soil Survey of Snohomish County Area Washington prepared by the United States Department of Agriculture. 36170/SEA3L280.doc Page 2 of 4 Copyright 2003 Kleinfelder, Inc. kn KLEINFELDER Groundwater Groundwater seepage was observed at depths of 6 to 6.5 feet below ground surface in two test pits. Because the test pits were open only for a short time period, the static water level was not confirmed. The Landau Associates (Landau) critical areas report encountered drain tiles on the west portion of the property. The drain tiles reportedly collect water from the east side of 7th Avenue and deliver it to the project site as a point source approximately 6 inches below the ground surface. REVIEW COMMENTS As previously stated, the purpose of our services was to provide third -party independent review of available geotechnical documents for the site. Based on our review of the referenced project, we offer the following review continents. Review Comment No. 1: Geotech's geotechnical report, Landau's critical areas report, and information provided by the local neighbors all identify the presence of yard waste on the site. However, the lateral and vertical extent and the material type and chemical make up of the yard waste has not been investigated. Consequently, the potential for impact to the development cannot at this time be determined. We suggest that the developer identify the lateral and vertical extent of the yard waste. The yard waste limits should be shown on a map with respect to the proposed home locations. The documents reviewed do not address the potential for chemical contamination of the soil and groundwater below the yard waste. Because the yard waste has been placed on this slope over several years, we believe that there is a potential that chemicals (such as total petroleum hydrocarbons) may have also been dumped along with the yard waste. We suggest that the developer prepare a sampling and analysis plan for evaluating soil and groundwater conditions beneath the yard waste. Site cleanup, if required, should be performed in accordance with Washington State and City of Edmonds regulations. Review Comment No. 2: The documents reviewed do not indicate whether the yard waste that might be located outside the residential home footprint will remain. We suggest that a slope stability study be performed to assess the potential for slope instability following site development if yard waste is to remain on the property. 36170/SEA3L.280.doc Page 3 of 4 Copyright 2003 Meinfelder, Inc. AdIlk k'q KLEINFELDER CLOSURE We will be pleased to discuss the above comments with you and representatives from the design team at your convenience. Should you have any questions or wish to arrange a meeting to discuss this letter, please call us at (425) 562-4200. Sincerely, KLEINFELDER, INC. James M. Schmidt, P.E. Senior Geotechnical Engineer 36170/SEA3L280.doc Page 4 of 4 Copyright 2003 Kleinfelder, Inc. 14 _t 0 F EDdr_ ti V BIRCH PL w Q CITY OF EDMONDS WATERLINE AS -BUILT d ADDRESS HOMEOWNER 1236 - 7th Avenue South Gerry Davis CONTRACTOR SCALE Mountain Shadow Construction NTS DATE DR4wn WATERLINE 7-7-2004 IBY K, Haney NO. 2003-1007 'n I m Tic Ac cT. -� Z703 Z S'06 3 0 f l 0 0 [ (.A r-'T` o F) -j- I S N 0 C7- Fl-Q'T' 18, 9 I (o S a.. t* , I/e-PeMN/,Otis SQF_FQ.GE 13 V I L..DI ►.i em t"ZQOF = Z.360 S. f=, 188 S.F. 0StIvE k W,&•t..V ' (o5Z_ S.r-. -r-o _r AlL = 3 z o 0 S F, CITY C 0 P vj& ; f 9 N N Z.q �l• w /jj e�uai GTt�U /I I PQ 1FS� I L--M-rt Oki /IotWtE F,!_-rerL .-rmtP ,RttCA y 5lLT l F�1-lGG �/ f4 LIU& CP A.cEA. c C dl / 1KlTlroa.Tr A 7- win z9a.81' N vt &;' o PVC DCTE TIOA! Cu-rL.E.T L._, LIC-- -r-0 D167.Il 1pIL-rIc. 1h + N N N 14 N I N ,4 t I I I V N a N W N ry N PLOT t�LW�i � N ?". G,4L•G S GoiZ I 5tfblEcT -ro K.oukxrf..j LJ S 1d A4,t=.OW c.o t.15T . A= L 3 0. 3 t�6 p O t 1�Ern1�ISTS o f sr' S-zoog -34 N %i AG.TuAL. ZloZ.�}- -- — — cx►S-rl"4 c.01.47ol) es J 37e) W.141> SGALE I"�Zo1 Ft1_L : 2..50 Gv. •IDS.e�A ITEGESS AUG,? 6 F�Mir cot FR Ae°o W-44- w FLOW zeS'rW_tc Z.A S. 3''D6x:Sot I DE7�C.iT10iJ o Go u ...-q- d h ¢_ � • 5.5, l,. C �GTE � 3 =J� 16 VeS 1 c i 89v CITY OF EDMONDS 121 5TH AVENUE NORTH • EDMONDS, WA 98020 • (425) 771-0220 • FAX (425) 771-0221 Website: www.oi.edmonds.wa.us DEVELOPMENT SERVICES DEPARTMENT Planning • Building • Engineering Mr. Al Jackson 16401 Highway 99 Lynnwood, Washington 98037 RE: 7th & Elm Short Plat Dear Mr. Jackson: October 21, 2003 GARY HAAKENSON MAYOR Thank you for so promptly responding to my request to provide a soils investigation report for the subject short plat. As my previous letter indicated, during the short plat review process the City received claims of unclean fill and construction debris illegally dumped and abandoned on your property. Because of the potential of contaminated soils and illegal .fill material placed on site, I required a soils report which you provided. Upon receipt of the GeoTech Consultants report dated September 3, 2003 I engaged the services of the City's peer review consultants, Kleinfelder who was tasked to review the report for sufficiency regarding the extent of soil exploration for contamination and plan for soil removal or remediation. Enclosed please find the Kleinfelder review letter dated October 15, 2003 (a copy has also been forwarded to Mr. James H. Strange, Jr. P.E. of GeoTech Consultants). The City shall require that Mr. Strange respond to the peer review comments and provide additional information, documentation or investigation in this matter as stated in the review letter. Note, once contaminated soils are found you are required by State Law to inform the Department of Ecology (local contact 425-649-7000) and follow their regulatory guidelines. The City Engineer shall continue to withhold final approval of the civil plans for this short plat until the GeoTech Consultant response is received, reviewed and approved by appropriate City staff, including but not limited to outside peer review as deemed necessary by the City. No additional building permit applications may be filed on this property until the civil plans are approved, and the building permit application filed under #03-458 shall not be issued until this matter is resolved thus it is in your best interests to expedite the response from Mr. Strange. If you have any questions please feel free to contact me during normal City business hours of 9:00am to noon and 1:00pm to 4:00pm, Monday through Friday at 425-771-0220 extension 1226. Sincerely, 6����rD Jeannine L. Graf Building Official Cc: Dave Gebert, City Engineer n�� ,oretc- A:uaus.` -11. 1890 cisfpr C'itu - HPkinan..)anan DATE RECEIVED 0 mh -2 Ili -�5 PERMIT EXPIRES CITY OF EDMONDS USE / PERMIT ZONE `� t/ NUMBER -- CONSTRUCTION PERMIT APPLICATION JOB SURUAPT* ADDRESS OWNER NAMEINAME OF BUSINESS PLAT NAME/SUBDIVISION N0. LOT Nq. UD N0. LID FEE t O� - �/,s � � � /VA�/� ,�►-, A /� iu , MAILING ADDRESS PUBLIC RIGHT OF WAY PER OFFICIAL STREET MAP RW Po Approves RW ReQulred �0j{� / L/ v O EXISTING _t_ PROPOSED et Street Uee Parms Req'd Inspection Required Sidewalk Required CITY ZIP TELEPHONE REQUIRED DEDICATION FT UndeVound NAME ��:� /� L �/Vrj � METER SIZE 1� LINE SIZE I�!j NO. OF FIXTURES /3 PRV REQUIRED YES NO 0 Z ✓[� p� C ADDRESS REMARK Z O OWNER/CONTRACTOR RESPONSIBLE FOR EROSION CONTROL/DRAINAGE CITY ZIP TELEPHONE 6v�i2�7C" k4, q21r 3S3-ark NAME `ON-�r CB p ') gfg- ENGINEERING REVIEWED BY DATE ' ' ADDRESS (� 61�f �t .FIRE, REVIEWED BY DATE to CITY ZIP TELEPHONEIEL zs���r-:�8z3 VARIANCE OR.CU 'SHORELINE OR AD Bq '" INSPECTION RE BOND POSTED STATE LICENSE NUMBER EXPIRATION DATE C CKED BY n,►Bv,,,�rsd g,�7�� /�9/©,SS ; oYEs O $. SEPA REVIEW COMPLETE . `.EXEMPT SIGN AREA 'ALLOWED,, 'PROPOSED HEIGHT TALLOW PROPOSED PROPERTY TAX ACCOUNT.PARCEL NO 'Z00 2?A3 3, 01(�c� EXP 1 2� 7 " NEW RESIDENTIAL PLUMBING I MECH LOT COVERAGE ALLOWED PROPOSED `• REQUIRED SETBACKS (Fr..), • FRONT %, SIDE,: ,REAR PROPOSED SETBACKS (FT.) FRONT L/RSI E REAR h COMPLIANCE OR ❑ ADDITION `❑ COMMERCIAL O, CHANGE USE D 2 �< �.' L3S .. , • I a Z_ _ OF. -,..,, REOD PARKING PROVIDED LOT AREA PLANNING REVIEWED BY ATE ❑ REMODEL ❑ . MULTIFAMILY ❑ SIGN 2. 2 REPAIR GRADINFENCE G " CYDS ❑ :. ( X FT) REMARKS, 1 r7 a S C Gt rv. —i c, �. OTHER ❑ DEMOLISH ❑ TANK ❑ ^✓11 GARAGE RETAINING WALL FRE SPRINKLER✓J ❑ Q CARPORT ROCKERY FIRE ALARM C k (TYPE OF USE BUSINESS OR ACTIVITY) EXPLAIN:. , Q C n /1� T/ M - CHECKED BY TYP F TRUCTION CO OCCUPANT s I` �lr ,I� LV .. GROUP NUMBER NUMBER OF CRITICAL a OF DWELLING AREAS SPECIAL INSPECTION AREA OCCUPANT O STORIES !� UNITS , NUMBER REQUIRED YES .'.; LOAD DESCRIBE WORK TO BE DONE REMARKS PROGRESS`INSPECTIONS PEWUSC 108/FINAL INSPECTION READ _ 9 _ e eti veil t f � Fly ; VALUATION &Q_ w ZoOo Vw At, ' Description ..FEE Des ription FEE Plan Check ` ` State Surcharge ` b HEAT SOURCE. GLAZING % 4;LOT-SLOPE % d-. \ , r A —. Buildih0eP Irmii ''' City Surcharge �- PLAN CHECK VESTED DATE 'Plumb ng.. ` Mechanical THIS PERMIT AUTHORIZES ONLY THE WORK NOTED. THIS PERMIT COVERS WORK TO It BE DONE ON PRIVATE PROPERTY ONLX ANY CONSTRUCTION ON THE PUBLIC Grading DOMAIN (CURBS, SIDEWALKS, DRIVEWAYS, MARQUEES, ETC.) WILL REQUIRE SEPARATE PERMISSION. Engr. Review m PERMITAPPLICATION: ISO DAYS 4 PERMIT LIMIT.1 YEAR - PROVIDED WORK IS STARTED WITHIN 180 DAYS Engr. Inspection SEE BACK OF PINK PERMIT FOR MORE INFORMATION 'APPLICANT, ON BEHALF OF HIS OR HER SPOUSE, HEIRS, ASSIGNS AND SUCCESORS Fire Review Plan Chk. Deposit r IN INTEREST, AGREES TO INDEMNIFY, DEFEND AND HOLD HARMLESS THE CITY OF 2 EDMONDS, WASHINGTON, ITS OFFICIALS, EMPLOYEES, AND AGENTS FROM ANY AND Fire Inspection Receipt It IALL CLAIMS FOR DAMAGES OF WHATEVER NATURE, ARISING DIRECTLY OR INDIRECTLY FROM THE ISSUANCE OF THIS PERMIT. ISSUANCE OF THIS PERMIT SHALL NOT BE 9 an Ldsca a Ins DEEMED TO MODIFY, WAIVE OR REDUCE ANY REQUIREMENT OF ANY CITY ORDINANCE P P• Total Amt. Due = NOR LIMIT IN ANY WAY THE CITY $ ABILITY TO ENFORCE ANY ORDINANCE PROVISION.*9 Recording Fee Receipt # ON V NEBY IS ACKNOWLEDGE THAT I HAVE CORRECT; AND THAT 1 AM THE OWTHIS ER, ORPTHE DU YTAUTHORIZED AGENTHAT THE OFAPPLICATION APPROVAL GIVEN THE OWNER. I AGREE TO COMPLY WITH CITY AND STATE LAWS REGULATING CONSTRUC- CALL This application is not a permit until signed by the TION; AND IN DOING THE WORK AUTHORIZED THEREBY, NO PERSON WILL BE EMPLOYED Building Official or his/her Deputy: and Fees are paid, and IN VIOLATION OF THE LABOR CODE OF THE STATE OF WASHINGTON RELATING TO FOR INSPECTION receipt IsacknovNedgedInspace provided. WORKMEN'S COMPENSATION INSURANCE AND RCW 18.27. OFFICIAL NAT E SIGNATURE (OWNER AGE DATE SIGNED / E (425) ODATE 7— f 0� / 7 71-0220 • R ED BY ATE -J EN ON M 1333 IS UNLAWFUL TO USE OR OCCUPY A BUILDING OR STRUCTURE UNTIL A FINAL INSPECTION HAS BEEN MADE AND APPROVAL OR A CERTIFI- ORIGINAL -FILE YELL INS —1`1 CATE OF OCCUPANCY HAS BEEN GRANTED. UBC SECTION 109 PINK -OWNER GOLD -ASSESSOR 04/02 PRESS HARD -YOU ARE MAKING 5 COPIES GREEN- ACCOUNTING. 0 0 N88030'11"W 290:6, 192.99.1 _ 1 ; i BsaL. (TYP.) W W .907, S.F. I ��jj •I 1 I 1 I y L�WWW y EOTI°W r . 1 II W .y 19,139 S.W. SOILS TEST PIT W Y Lri py LOT �. u( 19W5 S.F ;JµpRIR 0 1$❑NL W ;,WN k WAU F 91Ii1- IAtil V(NI 14 ,I y LL W W y y W" W �. " �. W y �. W. W W W W W y W W y. " s m W11 '• 1 ` i L. (TYP.) ! I R Cl l �956 S.F. COT 3, 19.277 S.F. � i i 1• P, � t90.77.1, 1 IjI I �A �/ 40T T 18,9I6 S.F. ,'�8� \ r JJJ d��J6 690 Bs.a.L I. I • N88030'11"W 290.811 15 EXIST 12' CONC. CULVERT II' i1 I' II II' 1 I! I 17 1a Property Address: I 19 VI 7TH AVF .SOUTH GR. 30 Legal Descril THE SOUTH 265.2 FLEI NORTHWEST OLARTER OF NORTH, RANGE 3 EAST. EXCEPT THE EAST 30 R DEED RECORDED UNOER SITUATE IN THE COUNTY Basis of Bea PLATOFELM PLACE �— Project Datc PROJECT SITE AREA: TAX PARCEL NO.: EXISTING/PROPOSED L PROPOSED LAND USE: PROPOSED NUMBER 01 TOTAL BUILDING (FOOT PARKING REOUIRED: PARKING PROPOSED.'