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19817 MAPLEWOOD DR.PDF12198 19817 MAPLEWOOD DR INTEIROFFICE COMMUNICAONS DATE 195- 19 TO k c FROM �A,Jk) SUBJECT: t4c-;-W &0&125) lqgl-1 1t4ql,.-,wvvba noro Itt k IV, k4f 4- 0,, c cf kew, c As, 6)6f ak felifto?,le Se cvli 41.eff p s VA hev, -fv 71ej vilivIlne hw� dlt"5 c (,).�s aA7 W 6a' -7 -74 -30 /? vu4torpvp�, R E C E I V ED (of FED 191985- 1 PUBLIC WORKS TAX ACCOUNT/PARCEL NUMBER: BUILDING PERMIT (NEW STRUCTURE): COVENANTS (RECORDED) CRITICAL AREAS: ag -led DETERMINATION: E] Conditional Waiver Z?b6l'udy Required E] Waiver DISCRETIONARY PERMIT DRAINAGE PLAN DATED: PARKING AGREEMENTS DATED: EASEMENT(S) RECORDED FOR: PERMITS (OTHER): PLANNING DATA CHECKLIST DATED: SCALED PLOT PLAN DATED: SEWER LID FEE $: LID SHORT PLAT FILE: LOT: BLOCK: SIDE SEWER AS BUILT DATED:- SIDE SEWER PERMIT(S) #: 69 Zgj" SOILS REPORT DATED: STREET USE / ENCROACHMENT PERMIT #: WATER METER TAP CARD DATED: OTHER: 00 o 0 V- Lij .-j z < 4LI J14'-0 'w �x ;ot� 'o ,6 C, 0 \ o, .p f\ �6 PLOT PL/-\,NJ SC4, LIE: I"= 20'-0 LOT 18 M6.10LEWOOTO ESTf,,TM'S IE'Dmawlo-o , vv/kea", v 14 / 7 5-, qY ZONE dCS-9 S F T 0 1 S: 0 H'C'-- IG H T I N14 0, B - �985 n vs PA v e- T'Cee JP�L-:R C A,-rc H BA-5 114 (VENT), DETE1jT,0,, 'T C0H-rR0L CATCH P'PE LE"r 2 x �co v"E p �- BAStP4 SLOPE SYSTEM CROSS SECTION :-' PAGE 3 FOR OUTLET CONTROL DETAIL 0LJTLQT CONTROC — 4- SL.O.W To o Lf-r L-E T (RI P RAP OR KUNOF F -5 P R E A D E R) 2' - 2-' . (0" DE---P, 41- 16 " SPALLS A 2' 5A,_ tp 'USWEC) F?CC., UT L Z-r RIPRAP OUTLET ,3HED C- R-Ay IF L /-0 TREN r-�4 MIN 10' LONG 710��PLCW 1 4' PE'FLF p,,E. Be I Pvl RD 4" PERF PIPE WITH CAP5 RUNOFF SPREADE T STANDARD DRAINAGE PLAN DETENTION SYSTEM PACE I OF, Z3 for location- Z plan by phone da te DESIGN DATA System Imperm P i Number Area pkr� Orifice D, Ka L h n;—,-' NOTES .. 1. Call Engineering Division (771-3202) for pre6ackfill'and final inspections. 2. Responsibility for Operation and . maintenance of drainage systems on Private property fS the resoonsibility of the property owner(s). Material accumulated in the storage Pipe must - be Flushed out and removed from catc'h basins to allow Proper operation out let control orifice must be . The open at all times. kept CITY OF EDMONDS Q )YO ci rz 7-IA-11 -:P"f 7-0 7. C) 7z)rtl— ' lowdifod 4, PObfltjq SITE PLAN, SCALE: X, f ,r3 Av,m 0,00 51 -,a / wer _Cr eqA 'Z'!�7 6��;.cr.--Jcy -7i-v'4rL'd:- . )TE: DO NOT USE RUNOFF SPREADER ON SLOPES 'ER 15 PERCENT ( WITHOUT SPECIAL DESIGN ) STANDARD DRAINAGE PLAN DETENTION SYSTEM PAGE 2 OF 3 Ulu U, I CITY of EDINHOS RECENED ODE SEWER PERMIT For Inspection Call 771-3202 MA'k PERMIT NO. Zf2lg Address of Construction: / scription (Include all eas6ments) Owner and/or Builder: Contractor & License No: Singl:e Family Residence Multi -Family (No. of Units Commercial (No. of fixture Units Invasion into City Right -of -Way: No 41�� Yes (If Yes, Right -of -Way Construction Permit required. Call One -Call -Center (1-800-424-5555) before any excavation.) Cross other Private Property: No k"� -Yes (If Yes, easement required, attach legal description and county easement number.) PLEASE READ THE ITEMS LISTED ON THE BACK '-F _1]?A�r-' 'I certifr a comply I .�h t I Ka-veread and shall Date with the items listed on the,back. Assessment Fee: ,Receipt No.: Partial Inspection: ]�?E_AMQ RF--LN%D -rO GRIM PIPE DEP-r�A GW_ Comments Date Initial Final Inspection Approved: Date InitiO 00 Rejected: CD n �it i a�l Reason Date Ln .r. t* PERMIT MUST BE POSTED ON JOB SITE > White Copy File Green Copy Inspector, Buff Copy - Applicant The City of Edmonds Side Sewer Drawing EASEMENT NO . ............................. ------------ - NEW CONSTRUCTION CR REPAIRS 0 LID NO. 16-1 -------- ASMT. NO - ---------------- OWNER -- ----------- ------------------------------- CONTRACTOR ----- O.W.N-ER ------------------------------------------------------------ PERMIT NO. JOB ADDRESS --- 1 -9.9 1 -q M-fSRtX-- qO --- I)RIME ...... LEGAL DESCRIPTION: LOT NO. ---------------------------- BLOCK NO - ----------------------- EDMON�DS tl T ---------------------------------------------------------------------------------------------------------------------------- NAME OF ADDITION JAAPwe-w--o-0D .... G-5-rx-M.5 ----------------- z X 19817 3 0 t) W-0001-1 1175 (RE V.1 1/78) 4rc-*.wtsc 11 bp Approved: DATE .... By c-c"NeCT1014 Tb GKISIr %,rue 4. 61 DP. 0 MIH=09-1250 Geotechnical Engineering Report Lilley Residence Edmonds, Washington For Bob and Nancy Lilley I 17625-1301h Ave. NE, C102, Woodinville, WA 98072 Cornerstone Phone: 425-844-1977 Geotechnical, 'Inc',. Fax: 425-844-1987 August 30, 2002 Bob and Nancy Lilley 19817 Maplewood Drive Edmonds, Washington 98026 Geotechnical Engineering Report Lilley Residence Edmonds, Washington CG File No. 1339 Dear Mr. & Mrs. Lilley: INTRODUCTION This report presents the results of our geotechnical engineering evaluation at your residence located 19817 Maplewood Drive Edmonds, Washington, Vicinity Map, at in as shown on the Figure 1. We were provided with a plot plan from the original construction, dated January 28, 1985. The residence is located at the top of a steep slope, which has shown signs of recent movement. You have recently installed a modular block wall to provide stability for the steep slope. You observed signs of settlement around this modular block wall. You have requested that we prepare this report to provide recommendations for additional support for the residence and the steep slope. This report provides design loads and recommendations for the installation and design of anchors to provide resistance to lateral movement of the steep slope to the east of the residence. You have provided us with a copy of the plans for the existing residence, along with a map showing the approximate location of the existing side sewer line. The side sewer extends down the hillside to the main line near the toe of the slope. We do not know if the movement of the hillside has affected the side sewer. I I Geotechnical Engineering Report Lilley Residence August 30, 2002 CG File No. 1339 Page 2 You have also conducted a survey of the floor elevations within your residence, as directed by Cornerstone Geotechnical, Inc. staff. These elevations do not appear to vary significantly, indicating the building has not undergone detrimental settlement. We have been discussing different design options with you. We have tried to make recommendations that provide the greatest benefit per cost. Other options were discussed that provide a better safety margin, but are not economical. SCOPE The purpose of this study is to explore and characterize the subsurface conditions behind the house and around the modular block wall, and to present repair recommendations. Specifically, our scope of services as outlined in our Services Agreement, dated August 9, 2002, includes the following: I . Review available geologic maps of the area. 2. Evaluate the shallow subsurface conditions at the footing of the residence and behind the modular block wall. These explorations may include hand pits, Dynamic Cone Penetrometer Tests, or borings. 3. Prepare cross sections to illustrate the approximate extent of loose soils. 4. Meet with you to discuss options and recommendations for repairs to the residence or modular block wall. 5. Prepare a report discussing our observations and recommendations. We have also expanded our services with your authorization. SITE CONDITIONS Surface Conditions The existing one-story residence has a daylight basement open to the rear of the house, toward the east. It sits at the top of an easterly -facing steep slope. Behind the house, a concrete sidewalk leads to a wooden deck and a short staircase. These stairs step downward to an asphalt path. A modular block wall, approximately 4 feet in height, lies to the east of the residence. The ground surface slopes steeply downward to the east below the toe of the modular block wall. Cornerstone Geotechnical,. Inc. I I I 11 I I I 11 I I I I I I F I I I Geotechnical Engineering Report Lilley Residence August 30, 2002 CG File No. 1339 Page 3 The slope is vegetated chiefly with blackberries and other brush, with a few small deciduous trees. The areas to the north and south of this area are forested with brush, deciduous trees, and evergreen trees up to 3 feet in diameter. We observed signs of animals burrowing along the slope and within the forested areas. The upper deck, along with a portion of the upper floor of the existing residence, is supported on 4x4 timbers extending to 12-inch-diameter concrete piers. The plans for the existing residence indicate that the piers were to extend five feet below the ground surface. We observed piers leaning toward the steep slope that have been topped with an additional 2-foot-high vertical column of concrete. These improvements indicate that problems existed prior to your purchase of the house. We also observed signs of settlement, such as cracking, in the asphalt pathway and in the ground surface both above and below the modular block wall. Explorations Subsurface conditions were explored at the site on August 9, 21, and 22, 2002, by excavating three shallow test pits with hand tools, drilling a total of three borings with a portable hollow - stem -auger drill rig, and conducting four Dynamic Cone Penetrometer Tests. The explorations were logged by a geologist from this firm who also examined the soils and geologic conditions encountered. The Site Plan, Figure 2, shows the approximate locations of the explorations. The soils were visually classified in general accordance with the Unified Soil Classification System, a copy of which is presented as Figure 3. The samples were brought back to our laboratory for further classification. The logs of the hand pits are shown on Figure 4. The boring depths ranged from 16.0 to 30.3 feet. The boring samples were obtained at 2.5- or 5- foot intervals. The samples were obtained using the Standard Penetration Test (SPT) method in general accordance with ASTM D 1586. The SPT consists of driving a 2-inch-outside-diameter sampler using a 140-pound hammer falling 30 inches. The standard method is to drive the sampler 18 inches and record the blows for each 6 inches of penetration. The total number of blows for the last 12 inches of penetration (unless otherwise noted) is termed the Standard Penetration Resistance blow count or "N-value" (units: blows per foot). These values are shown on the boring logs, presented in Figures 5 through 7. I Cornerstone Geotechnical, Inc. Geotechnical Engineering Report Lilley Residence August 30, 2002 CG File No. 1339 Page 4 The Dynamic Cone Penetrometer Tests (DCPTs) consisted of driving a I O-square-centimeter point using a 35-pound hammer falling 15 inches. The standard method is to record the blows for each 10 centimeters of penetration. A computer program converts the counts into the Standard Penetration Resistance blow count or "N-value" (units: blows per foot). Figures 8 through I I present the results of the DCPTs. Subsurface Conditions Hand Pit 1, excavated to locate a concrete pier under the foundation, encountered wet fill material consisting of silty sand with drain gravel. This hand pit encountered the pier at a depth of approximately 1.5 feet. The plans indicate that this pier, along with the other piers planned for placement under the east footing of the residence, extends at least 4 feet downward. Hand Pit 2, excavated in the forested area immediately downslope of a Moot -diameter evergreen tree, encountered dry, loose, brown medium sand to the full depth explored. Hand Pit 3, excavated adjacent to an upper -deck -supporting concrete pier, did not encounter the bottom of the pier. Very loose to medium dense, medium to coarse sand extended to a depth of about 7 to 9 feet in each of the borings. The upper 3 feet of Boring 3, consisting of silty sand with gravel, similar to that encountered in Hand Pit 1, is probably backfill for the footing on the east side of the residence. Below the loose soil layer, the material consisted of medium dense to very dense gray medium to coarse sand. This material is interpreted as an advance outwash deposit that has been glacially consolidated. The depths of loose material indicated by the DCPTs generally agree with those indicated by our other explorations. Figure 12 shows the cross section from the existing residence eastward beyond our explorations, with the probable depth to the underlying dense soils. Except for the upper fill zone at Hand Pit 1, ground water seepage was not encountered in our explorations, and we did not encounter ground water seepage from the hillside. Global Stability Analysis We completed global stability analysis to determine the factor of safety against slope failure at the site using a computer program known as XSTABL, version 5.2. XSTABL is a two- dimensional, limit -equilibrium, slope stability program. The sections were analyzed using the Cornerstone Geotechnical, Inc. Geotechnical Engineering Report Lilley Residence August 30, 2002 CG File No. 1339 Page 5 Bishops method of slices. XSTABL generates random potential failure surfaces and determines their corresponding factors of safety with respect to failure. The factor of safety is defined as the ratio of the internal soil strength divided by the gravity driving forces that cause failure. By generating a large number of random surfaces, the factor of safety can be obtained as the lowest number calculated. We have assigned soil strengths as shown below: Soil Type Cohesion (psf) Phi -value (deg) Sand, Loose to Medium Dense 0 34 Advance outwash deposits consisting of Medium Dense to Very Dense 0 I 42 These geotechnical values were obtained by back -calculation using the existing geometry and assuming a factor of safety slightly less than 1.0. It has been our intent with our geotechnical. design to improve the stability of the steep slope by adding a tieback anchoring system. The design of lateral resistance was also determined using the XSTABL program. We calculated the lateral force per lineal foot that would be needed to establish safety factors. We determined that a static factor of safety of 1.5 could be achieved by placing anchors that could retain 4,300 pounds of lateral force per lineal foot of the residence (perpendicular to the slope face). The lateral resistance could come from one row of anchors installed into the steep slope east of the residence. CONCLUSIONS AND RECOMMENDATIONS General In our opinion, the stability of the steep slope can be improved to the above factors of safety with tieback anchors attached to a timber wall. The timber wall may not extend into native soils, but will help distribute the load laterally. Figure 13 shows the approximate location of the proposed timber wall, to be determined in the field by a geotechnical engineer. Figure 14 presents a typical I ICornerstone Geotechnical, Inc.. Geotechnical Engineering Report Lilley Residence August 30, 2002 CG File No. 1339 Page 6 cross-section showing the anchoring system with the no-load zone. These recommendations will increase the factor of safety of the slope. We have consulted with you that it would be best to stabilize the face of the steep slope above the wall with timber cribs or erosion -control mattings. These options will be discussed further, in the field, based on the actual conditions encountered during construction. We have consulted with you that it is best to complete anchor installation before the onset of the wet season. The timber wall will also be placed in a manner to conform to the hillside based on the morphology of the slope after the underbrush is cleared. Even though improvements will increase the residential structure stability, the hillside is very steep and will always have a potential of failure even though significant problems have not occurred in recent times. The hillside is at risk of slope movement, as shown by our explorations and analysis. This repair should significantly improve the risk of slope movement under the residence that would cause the residence to slide. The repair may not reduce risk of slope movement above and below the repair area. We understand that the anchors may be placed under the sanitary sewer east of the residence. It should be confirmed that the sewer line is shallow enough that there will be no potential damage from the anchor installation and possible anchor pullback during installation and/or testing. We expect the no-load zone will be significantly deeper than the sewer line and should not affect it. Based on the shallow ground water we encountered in Hand Pit 1 and Boring 3, both located near the side sewer, we recommend that the side sewer line should be checked for damage due to the movement of the hillside. We do not recommend direct discharge of water concentrated on to the steep slopes. It is best to collect water in pipes and tightline it down the slope. Concentrated water flow can cause significant erosion for the sandy soils at the steep slopes on the site. Lateral Resistance (Anchors) The anchored portion of any system should be located at a sufficient depth to develop resistance within the stable soil mass. We have estimated that a "no-load zone" be at least 5 feet into the Cornerstone Geotechnical, Inc.. Geotechnical Engineering Report Lilley Residence August 30, 2002 CG File No. 1339 Page 7 medium dense sand, as measured perpendicular from the slope face. The anchor type and length will be selected to satisfy requirements for lateral load and embedment. Anchors to resist lateral movement should withstand a lateral force of 4,300 pounds per lineal foot to achieve a static safety factor of 1.5 with respect to slope movement. The design capacity needs to be confirmed or modified using data obtained from load tests completed prior to produ ction tieback installation. Since a factor of safety for deep-seated failures of 1.5 is included in the design, it is our opinion that additional safety factors on the anchors are not needed. Two anchors should be load tested to 200 percent of the anchor design capacity. The load tests should consists of cyclic loading in increments of 25 percent of the design load, up to 200 percent of the design load or to failure, whichever comes first. The anchor may need additional steel to withstand the 200 percent load. If the 200 percent design value is not achieved, the anchor design capacity should be reduced to reflect a safety factor of 2 on ultimate capacity. The test location should be determined in the field based on soil conditions observed during excavation. All production anchors should be proof tested to 130 percent of design capacity. The testing program should be reviewed and monitored by the geotechnical engineer. Drainage We recommend that concentrated storm water not be allowed to directly discharge onto the slopes. All of the solid pipes should be connected and routed down the slope. The drainage system behind the wall should consist of 4-inch-diameter, perforated PVC pipe that is surrounded by free -draining material, such as pea gravel. The drains should discharge into tightlines leading to an appropriate collection and discharge point. USE OF THIS REPORT We have prepared this report for Bob and Nancy Lilley and their agents, for use in planning and design of this project. The data and report should be provided to prospective contractors for their Cornerstone Geotechnical, Inc. Geotechnical Engineering Report Lilley Residence August 30, 2002 CG File No. 13 3 9 Page 8 bidding and estimating purposes, but our report, conclusions, and interpretations should not be construed as a warranty of subsurface conditions. The scope of our work does not include services related to construction safety precautions, and our recommendations are not intended to direct the contractors' methods, techniques, sequences or procedures, except as specifically described in our report, for consideration in design. There are possible variations in subsurface conditions. We recommend that project planning include contingencies in budget and schedule, should areas be found with conditions that vary from those described in this report. We. should be retained to provide monitoring and consultation services during construction to confirm that the conditions encountered are consistent with those indicated by the explorations, and to provide recommendations for design changes, should the conditions revealed during the work differ from those anticipated. As part of our services, we would also evaluate whether or not earthwork and foundation installation activities comply with contract plans and specifications. Within the limitations of scope, schedule, and budget for our work, we have strived to take care that our work has been completed in accordance with generally accepted practices followed in this area at the time this report was prepared. No other conditions, expressed or implied, should be understood. now, Cornerstone Geotechnical, Inc. Geotechnical Engineering Report Lilley Residence August 30, 2002 CG File No. 13 3 9 Page 9 We appreciate the opportunity to be of service to you. If there are any questions concerning this report or if we can provide additional services, please call. Sincerely, Cornerstone Geotechnical, Inc. Jeff Laub Senior Staff Geologist 'PO"'Oki- is 1EXPIRES 081161,91 1 Rick B. Powell, PE Senior Engineer JPL:RBP:nt Two Copies Submitted Fourteen Figures cc: Mr. Will Bailey, Earth Firm (3 Copies) Cornerstone Geotechnical, Inc. Vicinity Map N I I. �nT X-1 K-T-� �ILU Proje Site A-- M E-E Cornerstone Phone: (425) 844-1977 Lilley residence agOello Geotechnical, Inc. Fax: (425) 844-1987 File Number Figure MP 17625-130th Ave NE, C-1 02 - Woodinville, WA - 98072 1339 1 1 I I I I I SITE PLAN Forested Area 3-foot.diameter evergreen tree LEGEND HP-1 Number and Approximate Location of Hand Pit DC-4 fy I? Forested ? Area ? Modular block wall �80 I? (Height = Approx. 4 feet) Approximate location of diameter side sewer (1 to 2 feet deep) VisiPY6 �* CrAcking 90 Piers supporting -3' upper level --------------------- Brg D ? DC-1 ? HP-3 ? ? 1 QO OPW XY NO Piers had previous movement and have been realigned B-1 Asphalt Number and Approximate Location of Soil Boring Driveway DC-1 Number and Approximate Location of Dynamic Cone Penetrometer Test 0 10 20 Scale 1 10' Topography is approximate based on measurements using a construction level with stadia. Local variations may exist. Elevation (ft) is based on an assumed datum of 100'. Unified Sbil- Cl-assification System MAJOR DIVISIONS GROUP GROUPNAME SYMBOL GRAVEL CLEAN GRAVEL GW WELL -GRADED GRAVEL, FINE TO COARSE GRAVEL COARSE - GRAINED MORE THAN 50% OF GP POORLY -GRADED GRAVEL COARSE FRACTION GRAVEL GM SILTY GRAVEL SOILS RETAINED ON NO. 4 SIEVE WITH FINES GC CLAYEY GRAVEL MORE THAN 50% RETAINED ON number 200 SIEVE SAND CLEAN SAND SW WELL -GRADED SAND, FINE TO COARSE SAND SID POORLY -GRADED SAND MORE THAN 50% OF SAND COARSE FRACTION PASSES NO. 4 SIEVE WITH FINES SM SILTY SAND SC CLAYEY SAND SILTAND CLAY INORGANIC ML SILT FINE - CL CLAY GRAINED LIQUID LIMIT LESS THAN 50% SOILS ORGANIC OL ORGANIC SILT, ORGANIC CLAY MORE THAN 50% PASSES NO. 200 SIEVE SILTAND CLAY INORGANIC MH SILT OF HIGH PLASTICITY, ELASTIC SILT CH CLAY OF HIGH PLASTICITY, FAT CLAY LIQUID LIMIT 50% OR MORE ORGANIC OH ORGANIC CLAY, ORGANIC SILT HIGHLY ORGANIC SOILS PT PEAT NOTES: SOIL MOISTURE MODIFIERS 1) Field classification is based on Dry- Absence of moisture, dusty, dry visual examination of soil in general to the touch accordance with ASTM D 2488-83. 2) Soil classification using laboratory Moist- Damp, but no visible water .tests is based on ASTM D 2487-83. Wet- Visible free water or saturated, 3) Descriptions of soil density or usually soil is obtained from consistency are based on below water table interpretation of blowcount data, visual appearance of soils, and/or test data. Cornerstone Phone: (425) 844-1977 Unified Soil Classification System Geotechnical, Inc. Fax: (425) 844-1987 Figure 3 17625-130th Ave NE, C-102 - Woodinville, WA* 98072 LOG OF EXPLORATION DEPTH Usc SOIL DESCRIPTION HAND PIT ONE 0.0-0.2 0.2-2.0 HAND PIT TWO 0.0-0.5 0.5-5.0 HAND PIT THREE 0.0-0.2 0.2-4.0 BARK DUST SP-SM BROWN SILTY MEDIUM,TO COARSE SAND WITH GRAVEL (LOOSE TO MEDIUM DENSE, MOIST TO WET) (FILL) SAMPLE WAS COLLECTED AT 1.5 FEET GROUND WATER SEEPAGE WAS ENCOUNTERED AT 1.0 FEET SLIGHT HAND PIT CAVING WAS OBSERVED FROM 1.5 TO 2.0 FEET FOUNDATION OBSERVED FROM 0.0 TO 1.5 FEET CONCRETE PIER OBSERVED FROM 1.5 TO 2.0 FEET; DID NOT LOCATE BOTTOM OF PIER HAND PIT WAS COMPLETED AT 2.0 FEET ON 8/9/02 FOREST DUFF SP BROWN MEDIUM SAND WITH TRACE GRAVEL AND ROOTS (LOOSE TO MEDIUM DENSE, DRY TO MOIST) (WEATHERED OUTWASH) SAMPLE WAS COLLECTED AT 5.0 FEET GROUND WATER SEEPAGE WAS NOT ENCOUNTERED HAND PIT CAVING WAS NOT OBSERVED HAND PIT WAS COMPLETED AT 5.0 FEET ON 8/9/02 BARK DUST SM BROWN MEDIUM SAND WITH TRACE GRAVEL (LOOSE, MOIST) (WEATHERED OUTWASH) SAMPLES WERE NOT COLLECTED GROUND WATER SEEPAGE WAS NOT ENCOUNTERED SLIGHT HAND PIT CAVING WAS OBSERVED FROM 0 TO 4 FEET CONCRETE PIER OBSERVED FROM 0.0 TO.4.0 FEET; DID NOT LOCATE BOTTOM OF PIER HAND PIT WAS COMPLETED AT 4.0 FEET ON 8/9/02 CORNERSTONE GEOTECHNICAL, INC. FILE NO 1339 FIGURE 4 SOIL DESCRIPTION W 0� Standard Penetration Resistance b a- z W 0 (140 lb. weight, 30" drop) B-1 (6 2 < 0 0� W 0 Blows per foot J (n 0 0 Surface Elevation: 10 20 30 40 50 Dark brown to brown medium sand with silt, SP- roots, and organics (loose, moist) (Topsoil) Sm ----------------------------------------- Red-brown medium sand with gravel (loose, moist) (Landslide debris) Light brown medium to coarse sand with grave SP- 5 — ------- ... ... ....................... ...... (medium dense, moist) Sw Gray -brown medium sand with gravel (loose, dry) ------------------------------------------- Rust-stained brown -gray medium to coarse 10 — -------............. .................. sand with gravel (dense, moist) (Advance Outwash) Brown -gray medium to coarse sand with gravel (very dense, moist) (Advance Outwash) N"26-50(6") 7 15- ..... ................ ... ....... ............. Gray medium sand with trace gravel N=24-28-36 41 (very dense, moist) (Advance Outwash) SP- SW Gray medium to coarse sand with trace gravel 20 — ------- ....... ....... ................... .. N-22-50(.6") (very dense, moist) (Advance Outwash) Gray medium sand with trace gravel 25 — — ----- ....... ........ ....... ....... ... N-:-25-45(6") (very dense, moist) (Advance Outwash) Boring completed at 26.5 feet on 8/21/01 No ground water was encountered 30 . .......................... .................... LEGEND Depth 2- O.D. split spoon sample Liquid limit Impervious seal P Sample pushed driven. 0 Moisture content Water level TV Torvane reading, W O.D. thin -wall sample tons/if + Plastic limit Piezometer Up PP Pocket penetrometer reading, tons/fe NOTE: The stratification lines represent the approximate boundaries between soil types and the transition may be gradual. Cornerstone 'Phone: (425) 844-1977 Lilley residence Fax: (425) 844-1987 Geotechnical, Inc. EFFile Number Figure 17625-130th Ave NE, C-102 - Woodinville, WA - 98072 1339 1 5 SOIL DESCRIPTION W w Standard Penetration Resistance b _j CL z W X: :D F_ (140 lb. weight, 30" drop) B-2 0 2 0 (L of uj 0 Blows per foot 0 Surface Elevation: 10 2jD 30 40 50 Dark brown medium sand with organics, SP- silt SM Brown medium to coarse sand with gravel (loose, moist) (Fill) Brown medium to coarse sand with gravel SP- Sw 5 .................................. ...... and a piece of plastic (very loose, moist) Rust -stained brown -gray medium sand with trace gravel (loose, moist) ----------------------------------------- Slightly rust -stained gray medium sand with 10 - ------- trace gravel (dense, moist) (Advance Outwash) Rust -stained gray medium to coarse sand with 15 - - ----- ....... ........................ . ..... trace gravel (very dense, moist to wet) (Advance Outwash) Gray medium sand with trace gravel SP- 20 - -------------. .......................... .. (very dense, moist) (Advance Outwash) Sw N=19-50(5")4 Gray medium to coarse sand with trace gravel 25 - - ----- ....... ........ ......................... N=50($") 41 (very dense, moist) (Advance Outwash) Gray medium to coarse sand with trace gravel 30 - - ------ ....... ........... .... W (very dense, moist) (Advance Outwash) Boring completed at 30.3 feet on 8/22/02 No ground water was encountered 351 ............. LEGEND Liquid limit Impervious sea[ P Sample pushed Depth 2- O.D. split spoon sample 'M Moisture content Water level TV Torvane reading, driven. . tons/ft' + Plastic limit Piezometer tip PP Pocket penetrometer 3" O.D. thin -wall sample reading, tons/fe NOTE: The stratification lines represent the approximate boundaries between soil types and the transition may be gradual. Cornerstone Phone: (425) 844-1977 Lilley residence Geotechnical, Inc. Fax: (425) 844-1987 1 File Number Figure 17625-130th Ave NE, C-1 02 - Woodinville, WA - 98072 1339 1 6 SOIL DESCRIPTION U) W Of Standard Penetration Resistance B-3 d _j (L z W :lf :) �_' I`_ (140 lb. weight, 30" drop) (6 2 < 0 a_ W 0 Blows per foot J U) Surface Elevation: One foot below ground surfac) 10 29 30 40 50 17 Brown silty medium to coarse sand with gravel (medium dense, wet) (Fill) SM Does not Brown silty sand with gravel for 10", then extend Brown medium sand with trace gravel '4 below fill (loose, moist) (Fill) ��;r7 ;;�"crijr; -s7a_n;_W'11Ft7Tr;jjg7;\;�i �P- ....... ............... ....... ....... (loose, moist) (Fill) ------------ mm—m ----------- SW -------- Gray. medium to coarse sand with gravel (medium dense, moist) (Advance. Outwash) Rust -stained gray medium to coarse 10 . ....... ....... ....... .. .................... sand withtrace gravel& silt (dense, moist) SP- (Advance Outwash) Sw Gray medium to coarse sand with gravel (very dense, moist) (Advance Outwash) N"20-50(6") 15 . . ...................................... Slightly rust -stained gray medium to coarse N=25-50(6") sand with trace gravel (very dense, moist) (Advance Outwash) Boring completed at 16.0 feet on 8/22/02 Ground water perched in fill - not within the Advance Outwash 20 - ------- ...... . ............................. 25 - - ----- ....... ........ ................... 30 - - ------ ....... ....... ................... LEGEND Depth 2' O.D. split spoon sample Liquid limit Impervious seal P Sample pushed driven. N Moisture content Water level TV Torvane reading, 3" O.D. thin -wall sample tons/fe + Plastic limit Piezometer tip PIP Pocket penetrometer reading, tons/fe NOTE: The stratification lines represent the approximate boundaries between soil types and the transition may be gradual. Cornerstone Phone: (425) 844-1977 Lilley residence Geotechnical, Inc. Fax: (425) 844-1987 File Number 1 Figure 17625-130th Ave NE, C-;l 02 - Woodinville, WA - 98072 1339 7 1 1 WILDCAT DYNAMIC CONE LOG Page I of I PROJECT NUMBER: 1339 DATE STARTED: 08-09-2002 DATE COMPLETED: 08-09-2002 HOLE#: DC-1 CREW: Jeff Laub SURFACE ELEVATIONfeet below ground surfa PROJECT: Lilley residence WATER ON COMPLETION: Yes ADDRESS: 19817 Maplewood Drive HAMMER WEIGHT: 35 lbs. LOCATION: Edmonds, WA CONE AREA: 10 sq. cm BLOWS. RESISTANCE GRAPH OF CONE RESISTANCE TESTED CONSISTENCY DEPTH PER 10 cm Kg/CM2 0' 50 100 150 N' SAND & SILT CLAY 3 13.3 ... 3 VERY LOOSE SOFT 4 17.8 ..... 5 LOOSE MEDIUM STIFF I ft 3 13.3 ... 3 VERY LOOSE SOFT 4 17.8 ..... 5 LOOSE MEDIUM STIFF 5 22.2 ...... 6 LOOSE MEDIUM STIFF 2 ft 4 17.8 ..... 5 LOOSE MEDIUM STIFF 2 8.9 2 VERY LOOSE SOFT 4 17.8 ..... 5 LOOSE MEDIUM STIFF 3 ft 3 13.3 ... 3 VERY LOOSE SOFT I M 3 13.3 ... 3 VERY LOOSE SOFT 3 11.6 ... 3 VERY LOOSE SOFT 4 ft 2 7.7 2 VERY LOOSE SOFT 3 11.6 3 VERY LOOSE SOFT 3 11.6 3 VERY LOOSE SOFT 5 ft 3 11.6 3 VERY LOOSE SOFT 3 11.6 ... 3 VERY LOOSE SOFT 3 11.6 ... 3 VERY LOOSE SOFT 6 ft 2 7.7 2 VERY LOOSE SOFT 1 3.9 1 VERY LOOSE VERY SOFT 2 m 7 27.0 ....... 7 LOOSE MEDIUM STIFF 7 ft 35 119.7 .................................. - DENSE HARD 8ft 9 ft 3m 10ft I I ft 12 ft 4m 13 ft Cornerstone Phone: (425) 844-1977 Lilley residence Fax: (425) 844-1987 Geotechnical, Inc. File Number Figure 17625-130th Ave NE, C-102 - Woodinville, WA - 98072 1 1339 1 8 WILDCAT DYNAMIC CONE LOG HOLE #: DC-2 CREW: Jeff Laub PROJECT: Lilley residence ADDRESS: 19817 Maplewood Drive LOCATION: Edmonds, WA DEPTH I ft 2 ft 3 ft m 4 ft 5 ft 6 ft 2 m 7 ft 8 ft 9 ft 3 m 10ft I I ft 12 ft 4 m 13 ft Page I of I . PROJECT NUMBER: 1339 DATESTARTED: 08-09-2002 DATE COMPLETED: 08-09-2002 SURFACE ELEVATIO131ase of modular block w WATER ON COMPLETION: -No HAMMER WEIGHT: 35 lbs. CONE AREA: 10 sq. cm BLOWS RESISTANCE GRAPH OF CONE RESISTANCE PER 1.0 cm, Kg/CM2 0 50 100 150 N' 1 4.4 1 1 4.4 1 3 13.3 ... 3 2 8.9 2 2 8.9 2 3 13.3 3 3 13.3 3 4 17.8 ..... 5 5 22.2 ...... 6 9 40.0 ........... I I 11 42.5 ............ 12 12 46.3 ............. 13 9 34.7 .......... 9 7 27.0 ....... 7 6 23.2 ...... 6 6 23.2 ...... 6 10 38.6 ........... 11 6 23.2 ...... 6 6 23.2 ...... 6 4 15.4 .... 4 4 13.7 ... 3 7 23.9 ...... 6 8 27.4 ....... 7 8 27.4 ....... 7 12 41.0 ........... 11 22 75.2 ..................... 21 30 102.6 ............................. - 33 112.9 ................................ 50 171.0 ............................................... TESTED CONSISTENCY SAND & SILT ..CLAY' VERY LOOSE VERY SOFT VERY LOOSE VERY SOFT VERY LOOSE SOFT VERY LOOSE SOFT VERY LOOSE SOFT VERY LOOSE SOFT VERY LOOSE SOFT LOOSE MEDIUM STIFF LOOSE MEDIUM STIFF MEDIUM DENSE STIFF�' MEDIUM DENSE STIFF MEDIUM DENSE STIFF LOOSE STIFF LOOSE MEDIUM STIFF LOOSE MEDIUM STIFF LOOSE MEDIUM STIFF MEDIUM DENSE STIFF LOOSE MEDIUM STIFF LOOSE MEDIUM STIFF VERY LOOSE SOFT VERY LOOSE SOFT LOOSE MEDIUM STIFF LOOSE MEDIUM STIFF LOOSE MEDIUM STIFF MEDIUM DENSE STIFF MEDIUM DENSE VERY STIFF MEDIUM DENSE VERY STIFF DENSE HARD DENSE HARD Cornerstone Phone: (425) 844-1977 Lilley residence Geotechnical, Inc. Fax: (425) 844-1987 File Number Figure 17625-130th Ave NE, C-1 02 - Woodinville, WA - 98072 1 1339 1 WILDCAT DYNAMIC CONE LOG HOLE #: DC-3 CREW: Jeff Laub PROJECT: Lilley residence ADDRESS: 19817 Maplewood Drive LOCATION: Edmonds, WA DEPTH I ft 2 ft 3 ft I m 4 ft 5 ft 6 ft 2 m 7 ft 8 ft 9 ft 3 m 10ft I I ft 12 ft 4 m 13 ft PROJECT NUMBER DATESTARTED DATE COMPLETED Page I of I 1339 08-22-2002 08-22-2002 SURFACE ELEVATION: Base of steep scarp WATER ON COMPLETION: No HAMMER WEIGHT: 35 lbs. CONE AREA: 10 sq. cm BLOWS RESISTANCE GRAPH OF CONE RESISTANCE TESTED CONSISTENCY PER 10 cm Kg/CM2 0 50 100, 150 N' SAND & SILT CLAY 1 4.4 1 VERY LOOSE VERY SOFT 4 17.8 ..... 5 LOOSE MEDIUM STIFF 5 22.2 ...... 6 LOOSE MEDIUM STIFF 2 8.9 2 VERY LOOSE SOFT 3 13.3 3 VERY LOOSE SOFT 5 22.2 ...... 6 LOOSE MEDIUM STIFF 8 35.5 .......... 10 LOOSE STIFF 1 4.4 1 VERY LOOSE VERY SOFT 1 4.4 1 VERY LOOSE VERY SOFT 0 0.0 0 VERY LOOSE VERY SOFT 1 3.9 1 VERY LOOSE VERY SOFT 1 3.9 1 VERY LOOSE, VERY SOFT 2 7.7 2 VERY LOOSE SOFT 9 34.7 .......... 9 LOOSE STIFF 12 46.3 ............. 13 MEDIUM DENSE STIFF 12 46.3 ............. 13 MEDIUM DENSE STIFF 13 50.2 .............. 14 MEDIUM DENSE STIFF 13 50.2 .............. 14 MEDIUM DENSE STIFF 12 46.3 ............. 13 MEDIUM DENSE STIFF 12 46.3 ............. 13 MEDIUM DENSE STIFF 13 44.5 ............ 12 MEDIUM DENSE STIFF 10 34.2 ......... 9 LOOSE STIFF 35 119.7 .................................. - DENSE HARD 35 119.7 .................................. DENSE HARD 27 92.3 .......................... - MEDIUM DENSE VERY STIFF 25 85.5 ........................ 24 MEDIUM DENSE VERY STIFF 25 85.5 ................... 24 MEDIUM DENSE VERY STIFF 37 126.5 ................ - DENSE HARD 38 130.0 ...0 ........ 0 ........................ - DENSE HARD 22 75.2 ..................... 1 21 MEDIUM DENSE VERY STIFF Cornerstone Phone: (425) 844-1977 Lilley residence Geotechnical, Inc. Fax: (425) 844-1987 File Number F gure 17625-130th Ave NE, C-1 02 - Woodinville, WA - 98072 1 13N 1 10 WILDCAT DYNAMIC CONE LOG Page I of I PROJECT NUMBER: 1339 DATE STARTED: 08-22-2002 DATE COMPLETED: 08-22-2002 HOLE #: DC-4 .CREW: Jeff Laub SURFACE ELEVATIONorth of residence (wood PROJECT: Lilley residence WATER ON COMPLETION: No ADDRESS: 19817 Maplewood Drive HAMMER WEIGHT: 35 lbs. LOCATION: Edmonds, WA CONE AREA: 10 sq. cm BLOWS RESISTANCE GRAPH OF CONE RESISTANCE TESTED CONSISTENCY DEPTH PER 10 cm Kg/cm2 0 50 100 150 N' SAND & SILT � CLAY 1 4.4 1 VERY LOOSE VERY SOFT 1 4.4 1 VERY LOOSE VERY SOFT- 1 4.4 1 VERY LOOSE VERY SOFT 2 8.9 2 VERY LOOSE SOFT 1 4.4 1 VERY LOOSE VERY SOFT 2 ft 2 8.9 2 VERY LOOSE SOFT 3 13.3 3 VERY LOOSE SOFT 5 22.2 ...... 6 LOOSE MEDIUM STIFF 3 ft 12 53.3 ............... 15 MEDIUM DENSE STIFF I m 10 44.4 ............ 12 MEDIUM DENSE STIFF 10 38.6 ........... I I MEDIUM DENSE STIFF 4 ft 10 38.6 ........... I I MEDIUM DENSE STIFF 22 84.9 ........................ 24 MEDIUM DENSE VERY STIFF 21: 81.1 ....................... 23 MEDIUM DENSE VERY STIFF 5 ft 22 84.9 ........................ 24 MEDIUM DENSE VERY STIFF 6 ft 2 m 7 ft 8 ft 9 ft 3 m 10ft lift 12 ft 4 m 13 ft Cornerstone Phone: (425) 844-1977 Lilley residence Geotechnical, Inc. Fax: (425) 844-1987 File Number Figure 17625-130th Ave NE, C-102 - Woodinville, WA - 98b72 1 1339 1 11 CROSS-SECTION A -AV (SCALE 1:1) House Sidewalk S ew it He Pit Th ree Hand Ph Three Modular block wall Modular wall / Projected extent 4 1 of foundation pier. : ! (from plaruif* L-0 I Pier for upper deck - d e ow Tilling slightly dawmilope d Dram Drain mck pe ? __ Vwy ... .. r"hy 3' perf pi V.Y Brushy Slope pe p ? to to .L— D.. r to loo. C!fZ:_, ..... C_ Very lom Prob depth to dern soft to DC j�' ? Very to. to loose *vve expect that the foundation for the house is supported vertically on stable soil because no Medf— denee significant settlement is apparent M.A. in the house structure. to :4- ? DC-3 to -ry d— ? Me,—d X BI-2 .............. . ... . . ..................... Do to�d 0 10 B-1 20 Cornerstone Phone: (425) 844-1977 Lilley residence Fax: (425) 844-1987 Geotechnical, Inc. File Number igure Scale 1 1 Or 17625-130th Ave NE, C-102 Woodinville, WA - 98072 1339 12 I I I I I I I I I I 11 I I I I I 11 ? ? ? SITE PLAN Forested ? ? Area 80 Modular block wall (Height = Approx. 4 feet) ,.4 ? Approximate location of Proposed timber pile wall.with tiebacks spaced every fde-T 4" diameter side sewer (1 to 2 feet deep) (location to be determined in the field by geotechnical engi 1�r rn VisibF6 ? - ------------------- CrAcking —,Piers supporting upper level --- ----------------- Forested Area ? Topography is approximate based on measurements 0 10 20 using a construction level with stadia. Local variations may Cornerstone Phone: (425) E exist. Elevation (ft) is based Geotechnical, Inc. Fax: (425) Scale V = 10' on an assumed datum of 100'. no I TYPICAL ANCHORMALL DETAIL (SCALE = 1:1) Pmiected extent Tj 1-1111 of foundobw Per Pier (w upper docir - TUVng slighUy do —slope Veryloose I ID— Vy 1— D ProWbl. ftp#pv-...b 1 1V—UW1rk /-%1 1%11 lul - to be drilled at 0 b from horizontal 0 10 20 Scale 1 1 Or onrade slope above timber pile wall t 4 lowest slope possible; remove existing modular block wall SQ0y slope 6x6 timber pile with 6x6 timber lagging 'min. embedment B-1 09/04/2002 10:12 14258441987 CORNERSTONE GEOTEC PAGE. 0Z nerstone 17625-1301� Ave. NE, C102, WoodInville, WA 98072' Phone: 425-844-1977 igGeotechnical, Inc. Fax: 423-844-1987 September 3, 2002 Bob and Nancy Lilley 19817 Maplewood Drive Edmonds, Washington 98026 Geotechnical Letter — Emergency Slide Repair Lilley Residence Edmonds, Washington CG File No. 1339 Dear Mr. & Mrs. Lilley: STREET FILE. This letter presents our comments regarding the critical area requirements for the City of Edmonds. Your residence is located at 19817 Maplewood Drive in Edmonds, Washington Wc have previously written a geotechnical report to improve the stability of the site, dated August 30, 2002. We understand that the City of Edmonds has evaluated the site and concurs with our recommendation that improvements should occur on a timely basis. For this reason, the City of Edmonds has advised us that we should prepare this letter to formally request an exemption from the critical area study requirements because the slide has put the existing house at risk and rcquires an emergency basis to fix it prior to wet weather. 'Me slide is down slope of your house. We have provided recommendation's in our geotechnical report to improve the stability of the slope. These improvements will be directly down slope of the residence and will increase the factor of safety for deep-seated type failures. The planned improvements will consist of anchors and timber lagging. Timber lagging may extend up the slope in a crib pattem if the slope is too steep. The improvements will be on your property and will be installed to provide improvement to the stability of the slope behind the house. nerefore, we request that the critical area study requirements be exempted on this project. It is our intent only to stabilize the portions that need additional stability on an emergency basis. ATTACHMENT 2 09/04/2002 10:12 14258441987 CORNERSTONE GEOTEC PAGE 03 Geotechnical Letter — Emergency Slide leepair Lilley Residence September 3, 2002 CG File No. 1339 Page 2 We appreciate the opportunity to be of service to you. If there are any questions concerning this report or if we can provide additional services, please call. Sincerely, Cornerstone Geotechnical, Inc. VEXPIRES N Rick B, Powell, PE Senior Engineer -TPL:RBP:nt One Copy Submitted cc: Ms. Star Campbell, Development Services Department Mr. Will Bailey, Earth Firm Cornerstone Geotechnical, Inc. Date: To' From: MEMORANDUM September 10, 2001 Rob Chave, Planning Manager 'bC1 Star Campbell, Planning Division STREET FILE Subject: REQUEST FOR AN EMERGENCY EXEMPTION FROM CRITICAL AREAS REQUIREMENTS The purpose of this memo is to request an emergency exemption from critical areas requirements for 19817 Maplewood Dr. Introduction A Critical Areas Determination of Study Required has been made for the site because of the possibility of a Steep Slope Hazard Area on the site and a creek along the site's eastern boundary (See Attachment 1). The owners, Bob and Nancy Lilly, represented by Will Bailey for Earthfirm Inc. are seeking a solution to stabilize the slope at the site. A letter requesting an exemption to Critical Areas .requirements written by a Licensed Geotechnical Engineer, was submitted on September 4 th (See Attachment 2). This letter was accompanied by a Geotechnical Report for the site (See Attachment 3). The letter and the report state that revisions to the site are needed in order to stabilize the,slope. The revisions consist of a new timber retaining wall that will replace a concrete block rockery previously installed at the site (See Figure 2 of Attachment 3). Points of Consideration • A site visit was made for the Critical Areas Determination. While at the site, signs of erosion on the slope where observed. The signs of erosion are in close proximity to the house. These were documented with photographs taken at that site visit (See Attachments 4 through 8). • The stream is located near the east property line. The stream meets the definition of a Category 3 stream. As such, it requires 25' of protection (10' buffer / 15' building setback). The proposed revisions appear to be far enough away from the stream to be outside of this area of protection required for the stream. • A survey to show whether or not a steep slope hazard area exists on the site has not been submitted to the City. However, it appears that the location of the revisions would be within an area considered,to be' a steep slope hazard area. City of Edmonds czR Planning Division The proposed revisions appear to be only those that are necessary to stabilize the slope on an emergency basis. This was stated in the letter submitted by the geotechnical engineer (Attachment 3). ECDC Chapter 20.15.13.040 allows for an exemption from the regulations of the Critical Areas Chapter for "Emergencies that threaten the public health, safety and welfare as defined in ECDC 20.110.020(D)." ECDC 20.110.020(D) defines an emergency as, "a situation in which the community services director or his/her designee determines immediate action Js required to prevent or eliminate threat to health or safety or persons or property. Please review this request for an emergency exemption from critical areas regulations for the specific proposal as detailed in Attachment 3 and complete the following: Emergency Exemption Approved: (Check if applicable) Emergency Exemption Denied: (Check if applicable) Additional information will need to be reviewed before the exemption may be approved (Check if applicable) This information should consist of the following: Signed: —Robert.Chave, AICP, Planning Manager X 1I-&,>O- Date �'-o C. 18) 11 March I I y 2003 STREET FILE ,GARY HAAKENSON CITY OF EDMONDS MAYOR 121 STH AVENUE NORTH - EDMONDS, WA 98020 - (425) 771-0220 - FAX (425) 771-0221 Website: wwwci.edmondsma.us DEVELOPMENT SERVICES DEPARTMENT Planning # Building - Engineering Robert and Nancy Lilley 19817 Maplewood Drive 'Edmonds, WA 98026 RE: Geotechnical Update Dear Mr. and Mrs. Lilley: The purpose of this letter is to make a second request for a geotechnical update on the monitoring program instituted by Cornerstone Geotechnical, Inc. on your property last fall. As you recall pursuant to Cornerstone letter dated October 11, 2002 a monitoring survey program was to be installed using two inclinometer casings that will monitor horizontal deflection of the slope. Also, metal rebar pins were to be driven into the ground at the top of the slope to be observed by you on a weekly,basis to confirm any movement. Please direct Cornerstone to provide an update to the City and include the status of when a written plan will be submitted that includes a schedule for implementation for temporary and permanent slope protection and slope mitigation. As a reminder, recommendations in the plan shall consider the stability of the slope and seasonal weather conditions when establishing a time schedule for installation of the stabilization measures. Once this plan is provided the City will expedite the review and approval and permit issuance. Please provide the plan by April 11, 2003. If you have any questions please contact me directly at 425-771-0220 extension 1226. Sincerely, ��W� Jeannine L. Graf Building Official cc: Rick Powell, PE, Cornerstone Geotechnical, Inc. Incorporated August 11, 1890 Sister. City - Hekinan, Japan 4'.o C. 18 0 \3 CITY OF EDMONDS STREET FILE GARY HAAKENSON MAYOR 121 5TH AVENUE NORTH - EDMONDS, WA 98020 - (425) 771-0220 - FAX (425) 771-0221 Website: www.d.edmondsma.us DEVELOPMENT SERVICES DEPARTMENT Planning - Building - Engineering Robert and Nancy Lilley March 28, 2003 ,19817 Maplewood Drive,, Edmonds, WA 98026 RE: Lilley Permit Application 902-438 Dear Mr. and Mrs. Lilley: The City is in receipt of the Cornerstone Geotechnical letter dated March 6, 2003, (received by the City on March 21, 2003). The City accepts the recommendations of the engineer of record to continue to evaluate the slope and movement on your property. Although some slope movement is evident as stated in the geotech report; "This shallow movement, evident in our test results, should not affect the existing foundation system of the main building footprint because of the piers that underlying the main foundation system" there is no observable effect to the foundation of the residence. Any noted temporary erosion control measures should be made to insure the safety of the property. After future gebtechnical monitoring is complete, and if warranted by the test results, a written plan shall be submitted by your geotechnical engineer if temporary or permanent slope protection and slope mitigation is required, or, if further investigation determines that the house foundation system is affected by the slope movement or if structural repairs must be made to the deck. Please note that because the situation on your property has apparently stabilized, it is no longer considered an "emergency" under the City's critical areas ordinance, and therefore the previously issued emergency exemption no longer applies. Be aware'that any future work will have to' be evaluated under the City's critical areas regulations. If you believe that it is likely that you will want to pursue construction or alteration of your property, you should consider applying for applicable critical areas review(s) at the earliest available time to avoid any future delays due to a required City review. At this time the City is returning your plan submittal documents (enclosed). Some of these materials could be used in fature submittals should you need to pursue slope protection or slope mitigation on your property. If you have any questions please contact me directly at 425-771-0220 extension'1226. Sincerely, Jeannine L. Graf Building Official cc: Rick Powell, PE, Cornerstone Geotechnical, Inc. Will Bailey, Earthfirm, Inc. Rob Chave, Planning Manager Incorporated August 11, 1890 Sister City - Hekinan, Japan Cornerstone 17625-130th Ave. NE,C102, Woodinville, WA 98072 Phone: 425-844-1977 Geotechn'ical, In.c. Fax: 425-844-1987 F-, March 6, 2003 STREET FILE COUNTER Bob and Nancy Lilley 1-9�1 7 Maplewood Drive Edmonds, Washington 98026 Evaluation of Inclinometer Readings I F ILE' Lilley Residence Edmonds, Washington CG File No. 1339 Dear Mr. & Mrs. Lilley: This letter presents our evaluation of the inclinometer readings at two locations to the west of your residence, at the top of the steep slope. This letter also discusses the data from our shallow metal rebar monitoring program. /- In brief, our main concern on this project is the depth of the very loose to loose FILL and the unknown depth of your piers under your residence. We are not aware, at this time, if the piers extend through the fill or if they are built in accordance with the plans. The pier depths of 5 feet in accordance with the plans would not be adequate for the structure. We "suspect" the building piers. extend through the loose fill based'on the performance of the main structure, but we do not have evidence or documentation to support this. theory. Nonetheless, based on the cost to stabilize the slope and the unknowns if an engineered fix is absolutely necessary at this time, you have opted to monitor the lateral movement of the slope. We have installed the inclinometer casings and the rebar pins to evaluate if movement is occurring and the depth of movement. We installed four metal rebar pins into the ground near the top of the slope during October 2002. The distance from these pins to the building was measured by the owner on a weekly basis. The owner reported to us that slight movement occurred, approximately 0.1 to 0.2 inches, during initial weeks, but since has not showed any significant movement. Evaluation of Inclinometer Readings Lilley Residence March 6, 2003 CG File No. 1339 Page 2 On February 18, 2003, we re -measured the two inclinometer casings installed along the west side of the residence. The inclinometer readings were compared to the baseline readings taken October 25, 2002. The attached charts illustrate the downslope displacement at both points. The data indicates we have identified some shallow movement to a depth of approximately 6 feet at both locations. We did not find evidence of any movement deeper than 6 feet. No movement indicates the slope has a factor of safety of above 1.0 for the given time period. Based on our previous global stability analyses, the calculated factor of -safety is slightly above 1.0 using nonconservative soil values. The addition of ground water to the slope will significantly lower the factor of safety. For you information, typical new building standards would have a factor of safety of at least 1.5. We have also attached the cross section of the slope showing the density of the soil that cores the slope. We have also provided the location of the movement, which, in our opinion, correlates to a relatively shallow movement. This shallow movement, evident in our test results, should not affect the existing foundation system of the main building footprint because of the piers that underlying the main foundation system. -At this time, we understand that you wish to replant the steeper part of the slope with a better vegetation to improve the surface erosion and possibly any very shallow slough events. It is our opinion this is acceptable, but it should not give you any false preconceptions that the slope is stabilized with the plants. At a minimum, the monitoring program should be continued to confirm deep-seated movement has not occurred. Other options would be to locate the documentation of the foundation pier depths or somehow investigate the pier depths.' If the piers can be confirmed that they extend through the loose soils, then the risk of a slope failure affecting the building is relatively small. 000 Cornerstone Geotechnical, Inc. Evaluation of Inclinometer Readings Lilley Residence March 6, 2003 CG File No. 1339 Page 3 If there are any questions concerning this letter, or if we can provide additional services, please call. Sincerely, Cornerstone Geotechnical, Inc. I r-mmor MUIRTKEU-';� Rick B. Powell, PE Principal JPL:RBP:nt One Copy Submitted Attachments: Figure I Two Charts cc: Mr. Will Bailey, Earth Finn Cornerstone Geotechnical, Inc. Residence A P qj ed extent —4 Of fwwation Pier Plum)* Ui Pier for upper de�& ? TftV eqV9 ft downalop. 'Af! bm "We expect that the foundation for the house is supported vertically on stable soil because no significant settlement is apparent in the house structure. 0 10 20 In MEL Scale I" = 10' Deck CROSS-SECTION A -All (SCALE = 1:1) MThm S$q- L� to 1%, V.V b. V_ b— .1 D.— t. ry d.— 04 Estimated movement plane observed in inclinometer reading W% b— bM 1A.1kxnd._1 Very loose to loose fill or slide debris Medium dense or better outwash Cornerstone Phone: (425) 844-1977 Lilley Residence iw Geotechnical, Inc. 'ax: (425) W-1987 File Number Figure 17625-130th Ave N E, C-1 02 - Woodinville, WA - 98072 1 1339. 1 1 Lilley Residence - North Inclinometer A Direction (Baseline Data 10/26/62) -3.00 -2.00 -1.00 0.00 1.00 2.00 3.00 0 -6 CL Deflection (in) W 2/18/03 I-Illey Residence - South Inclinometer A Direction (Baseline Data 10/26/02) -3.00 -2.00 -1.00 0.00 1.00 2.00 3.00 CL 26 Deflection (in) 2/1 a:M7] EarthfirmcN Jeannine Graf Building Official 121 5h Avenue North Edmonds, WA 98020 Dear Jeannine, STREET FILE 144 Landslide Restoration Ar Erosion Control z Native Plantings Stability yot! can bank- on! BUILDING. NOY 2002 November 1, 2002 This letter follows your letter of October 29, 2002 accepting Cornerstone's reco . mmendations for temporary erosion control measures and monitoring. We have completed the tern . porary erosion control measures recommended in Cornerstone's letter dated October 11, 2002. Thank you for your help with this project. Please feel free to contact me if you have further questions or concerns. Thank you, EARTHFIRM INC. William P. Bailey. General Manager Cc: Bob and Nancy Lilley Rick Powell, Cornerstone GeotechniCal P 0. Box 633 z Monroe, WA. 982 72 x Ph. (425) �71-5614 x Fax (360) 668-44 70 Lj J ��l xT "Ott, IN-1k, 17 , I -QN ;Z� - 1-4 AV, d�r, , VC �o 'r '4-;l 4 A Rj, Al its u IN Z pv It kz, I F� F-�; 1, 'A 'I Nk ly, 1�; UP A V, t.Dvq, Iv Lz, A = = w A I;oV/, I- Al ;Wllti 'Will M-0 Alp "M-li-w-1; Lk- -7�* . Im AW M MA 0 ICM AV 4 ZI Ile Fo' y- -t- 7-7 pry ;V� Ip AA- k 4%6, I P -X r,10 re .... ..... AMMMA '40 a -4 IA AW ;q Sm AVIM Ww, 4v Im sw I 'W" �'A' A W"ow AM �-GJ� 54 f !, "OWN, Own - Cm Wass 901 k�f -!?, 0- �, X 3 J7. _WN#*jv. VA% I ji Km 4.7 Zia 'W .4 -4 CITY OF EDMONDS FILE CRITICAL AREAS DETERMINMEET Site Location: 19817 Maplewood Drive Tax Acct. Number: 5067-000-018-00-04 Determination: Study Required Determination #: CA-02-180 Applicant: Will Bailey for Bob Lilley Owner: Bob Lilley CRITICAL AREAS DETERMINATION: STUDY REQUIRED (CA-02-180) During review and inspection of the subject site, it was found that the site may contain critical areas, including a Steep Slope Hazard Area and a Stream pursuant to Chapter 20.1513 of the Edmonds Community Development Code (ECDC). STUDY REQUIREMENT — STEEP SLOPE HAZARD AREA To determine if a Steep Slope Hazard Area does exist, prior to submission of any development permit, you will be required satisfy the requirements of the Critical Areas Chapter by completing the following Steep Slope Hazard Area Delineation Requirements: A topographic survey must be completed that delineates any Steep Slope Hazard Areas prepared by a Licensed Land Surveyor. [A steep slope hazard areas is defined by the Edmonds Community Development- Code as ground that rises at an inclination of 40% or greater within at least 20 feet of elevation change. In order to delineate a steep slope hazard area, it is necessary to locate the top and toe of the slope. The inclination of the slope is established by averaging the inclination over at least 20 feet of vertical relief. A steep slope hazard area is bordered by a 50 foot wide buffer measured from both the top and the toe of the steep slope hazard area. Adjacent to the buffer, there is a 15 feet wide building setback.] In order to complete this Study Requirement, this map must be submitted to the Planning Division for review and approval. DEVELOPMENT PROPOSALS ON A SITE WITH STEEP SLOPE HAZARD AREAS Development is restricted within the Steep Slope Hazard Area, its buffer, and/or building setback. If development must occur within these areas, the applicant may pursue certain processes provided in the Critical Areas Chapter of the Edmonds Community Development Code. The applicable process depends on the specific development proposal and site but may include one of the following: o For development proposals within the 50-foot buffer, but no closer than 10 feet from the top or toe of the slope, the 50-foot buffer requirement may be reduced to 10 feet if a study is completed by a licensed geologist or geotechnical engineer which clearly demonstrates that the proposed buffer alteration will have no adverse impact upon the site, the public or any private party. This is a process through which development could be allowed as close as 25'frorn the top or toe of the slope (assuming the buffer may be reduced to 10'— the 15' building setback still applies). o Development proposals closer than 25' from the top or toe of the slope may be allowed through the approval of a Steep Slope Exemption, Critical Areas Variance, or Reasonable Use Exception. These are Land Use Permits that must be obtained through the Planning Division. If you think your specific development proposal may require one of these processes, contact a Planner for more information. ATTACHMENT 1 M STUDY REQUIREMENT — STREAM The site investigation has shown that the site may contain a stream near the eastern boundary of the lot. This stream fits into the definition of a Category 3 stream as defined by ECDC .20.15B.060.A.4(c). This is a stream that does not run year-round and is not used by salmonids. Based on the above finding, a Critical Areas Study is required to locate the stream on the property. Stream' Delineation: A surveyor licensed by.the State of Washington must, perform the Tollowiri g: • Physically mark the edge of the stream. • Delineate the required buffer (refer to ECDC 20. 1 5B. 120. (A) for the required buffer widths). • D elineate the required building setback from the buffer (required setback is 15 feet). o Create a map showing the stream, the buffer and the building setback. In order to complete this Study Requirement, this map must be submitted to the Planning Division for review and approval. NOTE: One survey may be completed that shows any steep slopes and the stream. DEVELOPMENT PROPOSALS ON A SITE WITH A STREAM Development proposals that encroach into the stream buffers or building setbacks may be allowed through the approval of certain processes. The specific process depends on the individual site and development proposal but may include Buffer Averaging, a Critical Areas Variance, and/or a Reasonable Use Exception. If you think that you have a proposal thatmay require one of these processes, please contact a Planner for more information. I PROJECT SPECIFIC CONDITIONAL WAIVERS If the property ownerwishes to apply for a specific development permit which they feel would not impact the Critical Areas located on the site, they may submit their proposal to the Planning, Department for review. If the Planning Department finds that the proposed development permit will.not adversely impact a Critical Area or its buffers, a conditional waiver may be issued on a project by project basis. EXEMPT DEVELOPMENT PROPOSALS Certain development proposals may be exempt from Critical Areas Requirements (ECDC 20.15B.040). If you think that a specific development proposal may be exempt, contact a Planner for more information. Name Sighature Date o Cited sections of the Edmonds Community Development Code (ECDC) can be found on the City of Edmonds website. at www.ci.edmonds.wa.us. 2 City of EdmouAs Development Services Department Planning Division Phone: 425.771.0220 Fax: 425-771.0221 The Critical Areas Checklist contained on this form is to be filled out by any person preparing a Development Permit Application for the City of Echnonds prior to his/her submittal of the application to the City. ne purpose of the Checklist is to enable City staff to determine whether any potential Critical Areas are, or may be, present on the subject property. The inforniation needed to complete the Checklist should be easily available from observations of the site or data available at City Hall (Critical areas inventories, maps, Or soil surveys). Date Received: - a -7 — 0 City Receipt #: 4 r---7 IR Critical Areas File #*. Ch-02-- ISO Critical Areas Checklist Fee: $45.00 Date Mailed to Applicant, A property owner, or his/her authorized representative, must fill out the checklist, sign and date it, and submit it to the City' The City will review the checklist, make a precursory site visit, and nuke a determination of the subsequent. steps necessary to complete a development pamit application. Please submit a vicinity map, along with the signed copy of this form to assist City staff in finding and locating the specific piece of property described on this forrii. In addition, the applicant shall include other pertment information (e.g. site plan, topography map, eft.) or studies in conjunction with this Checklist to assistant staff in completing their preliminary assessment of the site. The undersigned applicant, and his/her/its heirs, and'assigns, in consideration on the processing of the application agrees to release, indemnify, defend and hold the City of Edmonds harmless from any and all damages, including reasonable attorney's fees, arising from any action or infi-action based in whole or part upon false, misleading, inaccurate or incomplete infonnation "shed by the applicant his/her/its agents o I r employees. By MY signature, 1 certify that the information and exhibits herewith submitted are true and correct to the best of my knowledge and that I am authorized to file this application on e behalf of the owner as listed below. SIGNATURE OF APPLICANTIAGENT —DATE. Property Owner"s Authoilzation By my signature, I certify that I have authorized the above Applicant/Agent to apply for the subject land use application, and grant my permission for the public officials and the staff of the City of Edmonds to enter the subject property for the. purposes of inspection and p�sting 9�tendant to this application. IL "j fffl �L4 Owner/AppHeant: —&o� Li u-ek Name I -1 M*PLEz) Cob Savet Addrm city State zip Telephone: IhS G-71 1145 Email address (optional):. AppHeant Representative: k,Z'1LA_ Name 7,24A,40 t4c + Street Address U_—CCx:)t wwff- LA `7SO_4� city Stalte zip Telephone: Lf2-S Email Address (optional): CH&W Aim ChaklisLdoc/3.19.2001 D- LU Lij < q'i o cj) lu -j Ab, " C, N PLOT PLA�,�j 'S C A, LIE: 1 20% 0 * LOT 16 M6,10LEWOOTO IESTAkYWS 0 .. zr . It 17 5'. Ajq 0 .ZONE X-al SETSAC KS: F R 0, N OTHER HEIGHT DA ZoneD N.W. 1/4, SEC. 19 T.27N.9 RA E.W.M. ISO /"07., % 10414 941 1 Tx': I PL . 21 MOD Aft 255-- 19M svew" 04Y MUM CMv 19504 ADVcHrIST Mat I-qw3 11583 c CD 96 -met ISI+ 13116 e. CwD- 1fw§j M703 19702 ?,two 1 709 411 Iq714 .720 M721 14 A449 low I th 19804 I"Of At It L WOO WX 19016 1"10 40 Ina so f IMP 4EM"Fi lab ST 2M TR s 2M got too" El sit 20104 L -LA 14 "to# #4 "W 11MIDMAIPOWD 801 LA I ir: I ;'- " soft 11'p 1 11 1 Man I N 110 ST u3jo aw tat$ WOO 20366 sass.2006 J20 a g"M 21=4 to 20310 0-il 20OW7 03 Ob ton gnu Is 263IR 17 04 1 low ANN arld I 1101011OL61LO-am 19829 19817 19830 19903 19905 19900 10 19911 % 19910 % % Ell k A Tie IF VAR Ne, 4-v 14 ;;Oo 4e 42,, le 4XI � on"),W4 jou V Ail 41:27— ov, STREET FILE GARY HAAKENSON CITY OF EDMONDS MAYOR 121 5TH AVENUE NORTH * EDMONDS, WA 98020 , (425) 771-0220 FAX (425) 771-0221 Website: wwwci.edmondsma.us DEVELOPMENT SERVICES DEPARTMENT �1- - - W-C M"o Planning - Building - Engineering I? C. 189 March 11, 2003 Robert and Nancy Lilley J-9817-Maplewbod Drive Edmonds,'WA' 98026 RE: Geotechnical Update Dear Mr. and Mrs. Lilley: The purpose of this letter is to make a second request for a geotechnical update on the monitoring program instituted by Comerstone Geotechnical, Inc. on your property last fall. As you recall pursuant to Cornerstone letter dated October 11, 2002 a monitoring survey program was to be installed using two inclinometer casings that will monitor horizontal deflection of the slope. Also, metal rebar pins were to be driven into the ground at the top of the slope to be observed by you ori a weekly basis to confinn any movement. Please direct Cornerstone to provide an update.to the City and include the status of when a written plan will be submitted that includes a schedule for implementation for temporary and permanent slope protection and slope mitigation. As a reminder, recommendations in the plan shall consider the stability of the slope and seasonal weather conditions when establishing a time schedule for installation of the stabilization measures. Once this plan is provided the City will expedite the review and approval and permit issuance. Please provide the plan by April 11, 2003. If you have any questions please contact me directly at 425-771-0220 extension 1226. Sincerely, ��W� Jeannine L. Graf Building Official cc: Rick Powell, PE, Cornerstone Geotechnical, Inc. Incorporated August 11, 1890 Sister. City.- Hekinan, Japan STREET FILE GARY HAAKENSON CITY OF EDMONDS MAYOR 121 5TH AVENUE NORTH - EDMONDS, WA 98020 - (425) 771-0220 FAX (425) 771-0221 Website: wwdedmondsma.us DEVELOPMENT SERVICES DEPARTMENT 117 C. Planning - Building * Engineering February 11, 2003 Robert and Nancy Lilley M17 Map-lewo'od Drive Edmonds, WA 98026 RE: Geotechnical Update Dear Mr. and Mrs. Lilley: The purpose of this letter is to request a geotechnical update on the monitoring program instituted by Cornerstone Geotechnical, Inc. sometime in October/November of 2002. As you recall pursuant to Cornerstone letter dated October 11, 2002 a monitoring survey program was to be installed using two inclinometer casings that will monitor horizontal deflection of the slope. Also, metal rebar pins were to be driven into the ground at the top of the slope to be observed by you on a weekly basis to confirm any movement. Please direct Cornerstone to provide an update to the City and include the status of when a written plan will be submitted that includes a schedule for implementation for temporary And permanent slope protection and slope mitigation. As a reminder, recommendations in the plan shall consider the stability of the slope and seasonal weather conditions when establishing a time schedule for installation of the stabilization measures. Once.this plan is provided the City will expedite the review and approval and permit issuance. If you have any questions please contact me directly at 425-771-0220 extension 1226. Sincerely, 4AW;`j�r Jeannine L. Graf Building Official .9 cc: Rick Powell, PE, Cornerstone Geotechnical, Inc. Incorporated August 11, 1890 Sister City - Hekinan, Japan 0. �f PC. 1891, STREET FILE GARY HAAKENSON CITY OF EDMONDS MAYOR 121 5TH AVENUE NORTH - EDMONDS, WA 98020 - (425) 771-0220 - FAX (425) 771 -=1 Website: www.dedmondsma.us DEVELOPMENT SERVICES DEPARTMENT Planning - Building - Engineering October 17, 2002 Robert and Nancy Lilley I , �817 Maple -wood Drive Edmonds, WA 98026 RE: Lille'y Retaining Wall Permit Application #02-438 Dear Mr. and Mrs. Lilley: On August f 1, 2002 the City received a permit application submitted by your contractor, Will Bailey of Earthfirm, Inc., to construct a timber pile wall with tiebacks to stabilize the east slope of your property. It was determined by your geotechnical engineer that the work to be done under this permit' was to stabilize the portions of the slope that need additional stability o . n an emergency basis' Due to the emergency nature of the request, an "emergency exemption for Critical Areas reqluirements" was approved as part of the permit review. The City's Building, Planning and En � ineering Divisions reviewed the application and sent corrections in a timely 9 manner, and are still awaiting responses to those corrections. The City was recently informed by your contractor, Will Bailey from Earthfirm, Inc., that you have chosen not to do the work as described in your permit application due to the cost of the project, but instead want to re -landscape the slope. In the Geotechnical Engineering Report dated August 30, 2002 and letter dated September 3, 2002, both prepared by Rick Powell of Cornerstone Geotechnical, Inc., he states that the hillside is at risk of slope movement, and that the repair should significantly improve the risk of slope movement under the residence that would cause the residence to slide. He also recommends that wall/anchor installation be completed before the onset of the wet season. Due to the significant nature of the statements made by your Geotechnical Engineer that have been brought to the City's attention, temporary slope stabilization measures must be made -immediately to insure the safety and welfare of the occupants of your house and property, as well as those in the adjacent public park. Therefore, it is my determination as Building Official for the City of Edmonds that by 5:00 pm November 1, 2002, a written plan shall be submitted by your geotechnical engineer, that includes a schedule for implementation for temporary and permanent slope protection and slope mitigation. Recommendations in the plan shall consider the stability of the slope and seasonal weather conditions when establishing a time schedule for installation of the. stabilization measures. Once this plan is provided the City will expedite the Incorporated August 11, 1890 Sister City - Hekinan, Japan review and approval and permit issuance. Be advised, field reports by the geotechnical engineer shall be. required to be provided to the City for all phases of work. If the permanent improvements include the ret9iningwall/anchor design that is currently in for plan review, the engineer of record. must respond to the outstanding plan review correctiotis from the Building, Planning and Engineering Divisions, so that the permit can be issued. Nothing in this letter * should be interpreted as waiving requirements to the Uniform Building Code or City discretionary permit approvals. I advise you to consult the Edmonds Planning Div ' ision, (Star Campbell, contact person), to determine what permits, if any, are required by the Planning Division. For building permit information, Lara Palmatier, Senior Permit. Coordinator" will be' your contact person. The purpose of this letter is to trigger your obligations under Washington State law, the State adopted Building Code and Edmonds City Ordinance #2661. Therefore, failure to comply with the terms. of these requirements, as modified in the future to incorporate your geotechnical engineer's recommendations, could result in civil or criminal liability. I trust that you will move p I romptly so enforcement measures will not be necessary. If you have any questions about this letter please contact me directly at 425-771-0220 extension 1226. Sincere ly, Jeannine L. Graf Building Official cc: Rick Powell, PE, Cornerstone Geotechnical, Inc. Will Bailey, Earthfirrn, Inc. -t-n C. 1891, I STREET FILE 4 CITY OF EDMONDS - GARY HAAKENSON MAYOR 121 5TH AVENUE NORTH. EDMONDS, WA 98020 '- <425) 771-0220 - FAX (425) 771-0221 DEVELOPMENT SERVICES DEPARTMENT Planning - Building - Engineering ' September 13, 2002 Rick B. Powell, P.E. Cornerstone Geotechnical Inc. 17625 130' Avenue NE, C102 Woodinville, Washington 98072 RE:. Lilley Repair project @ 1�817 Maplewood Drive . Dear Mr. Bail dy: in response to your voice mail message to me this morning, the purpose of this letteris to clarify City permitting requirements for the proposed work at the -subject property., It is ' my understanding that Will Bailey requested an emergency Critical'Areas waiver from the City Planning Manager,, Rob - Chave. Mr.- Chave has the authority to grant specific exemptions of Edmonds Community Development Code (ECDC) Chapter 20.15B. However, please be advised, waivers of ECDC 20.15B shall in no way waive or reduce Uniform Building Code (UBC) requirements for proposed grading, slope repair work, retaining wall construction, sewer repair work, etc. As Building Official for the City of Edmonds all provisions of the LJBC shall be satisfied before a building permit is issued. Earth Finn provided the City a letter dated September 3, 2002 that states, 'the slide has put the existing house at risk and requiresan emergency basis to fix it prior to wet weather' please note that your soils report dated 8/30/02 does not confirm this assessment, although the report does state that it is best to complete anchor installation before the onset of the wet season. However, because of this statement our permitting staff quoted an expedited review period which we will honor. The permit application and soils report were submitted by Earth Firm to the Building Division on September 11, 2002. My review was done the very next working day and notes four outstanding* requirements that shall be provided in order for the permit to be issued. I strongly suggest that you expedite the structural engineer's design and provide all other information as soon as possible in order for the work to start before wet weather. Sincerely,* Jeanriine L. trfaf Building Official Cc: Will Bailey, Earth Firm, Inc. Bob & Nancy Lilley Incorporated August 11, 1890 0 Sktpr rAhj - Hokinan Annan P i-1 �� (11 C. 1 89a STREET FILE CITY OF EDMONDS 121 STH AVENUE NORTH - EDMONDS, WA 98020 - (425) 771-= - FAX (425) 771-=1 Website: wwwd.edmondsma.us DEVELOPMENT SERVICES DEPARTMENT Planning - Building - Engineering . I October 29, 2002 Robert and Nancy Lilley 19817 Maplewood Drive �dtnonds, WA 98026 RE: Lilley Retaining Wall Permit Application #02-438 Dear Mr.* and Mrs. Lilley: GARY HAAKENSON MAYOR' The City is in receipt of the Cornerstone Geotechnical letter dated 10/11/02, (received by the City on October 25, 2002). The City accepts.the recommendations of the engineer of record to evaluate the slope utilizing a monitoring system priorto submitting a final plan for temporary and permanent slope protection and slope mitigation. All noted temporary erosion control measures must be made immediately to insure the safety and welfare of the occupants of the house, property and surrounding properties. After the geotechnical monitoring is complete, a written plan shall be submitted byyour geotechnical engineer, that includes a schedule for implementation -for temporary and permanent slope protection and slope mitigation. Recommendations in the plan shall co , nsider the stability of * the slope and s * easonal weather conditions when establishing a time schedule for installation of the stabilization measures. Once this plan is provided the City will expedite the review and approval and peftnit issuance. If you have any questions please contact me directly at 425-771-0220 extension 1226. Sincerely, Jeannine L. Graf Building Official cc: Rick Powell, PE, Cornerstone Geotechnical, Inc. Will Bailey, Earthfirm, Inc. Incorporated August 11, 1890 Sister C.itv - Hekinan. Janan CITY OF EDMONDS 121 5TH AVENUE NORTH - EDMONDS, WA 98020 - (425) 771-0220 FAX (425) 771-0221 Website: www.d.edmondsma.us DEVELOPMENT SERVICES DEPARTMENT C. Planning - Building - Engineering Robert and Nancy Lilley March 28, 2003 19817 Maplewood Drive Edmonds,- WA 98026 RE: Lilley Permit Application #02-438 Dear Mr. and Mrs. Lilley: GARY HAAKENSON . MAYOR The City is in receipt 'of the Cornerstone Geotechnical letter dated March 6, 2003, (received by the City on March 21, 2003). The City accepts the recommendations of the engineer of record to continue to evaluate the slope and movement on your property. Although some slope movement is evident as stated in the geotech report; "This shallow.movemeni, evident in our test results, should not affect the existing foundation system of the main building footprint because of the piers that underlying the main foundation system" there is no observable effect to the foundation of the residence. Any noted temporary, erosion control measures should be made to insure the safety of the property. After future geotechiiical monitoring is complete, and if warranted by the test results, a written plan shall be submitted by your geotechnical engineer if temporary or permanent slope protection and slope mitigation is required, or, if further investigation determines that the house foundation system is affected by the slope movement or if structural repairs must be made to the deck. Please note that because the situation on your property has apparently stabilized, it is no longer considered an "emergency" under the City's critical areas ordinance, and therefore the previously issued emergency exemption no longer applies. Be aware that any future work will have to be evaluated under the City's critical areas regulations. If you believe that it is likely that you will want to pursue construction or alteration of your property, you should consider applying for applicable critical areas review(s) at the earliest available time to avoid any future delays due to a required City review. At this time the City is returning your plan submittal documents (enclosed). Some of these materials could be used in future submittals should you need to pursue slope protection or slope mitigation on you'r property. If you have any questions please contact me directly at 425-771-0220 extension 1226. Sincerely, Jeannine L. Graf Building Official cc: Rick Powell, PE, Cornerstone Geotechnical, Inc. Will Bailey, Farthfirrn, Inc. - Rob Chave, Planning Manager Incorporated August 11, 1890 Sister City - Hekinan, Japan 4.4 C. 189 %j 0 � 0 CITY OF EDMONDS 121 5TH AVENUE NORTH - EDMONDS, WA 98020 - (425) 771-0220 * FAX (425) 771-0221 Website: www.d.edmonds.wa.us DEVELOPMENT SERVICES DEPARTMENT Planning - Building - Engineering Robert and Nancy Lilley March 28, 2003 19817 Maplewood Drive Edmonds, WA 98026 RE: Lilley Permit Application #02-438 Dear Mr. and Mrs. Lilley: GARY HAAKENSON MAYOR The City is in receipt of the Cornerstone Geotechnical letter dated March 6, 2003, (received by the City on March 21, 2003). The City accepts the recommendations of the engineer of record to continue to evaluate the slope and movement on your property. Although some slope movement is evident as stated in the geotech report; "This shallow movement, evident in our test results, should not affect the existing foundation system of the main building footprint because of the piers that underlying the main foundation system" there is no observable effect to the foundation of the residence. Any noted temporary erosion control measures should be made to insure the safety of the property. After future geotechnical monitoring * is complete, and if warranted by the test results, a written plan shall be submitted by your geotechnical engineer if temporary or permanent slope protection and slope mitigation is required, or, if further investigation determines that the house foundation system is affected by the slope movement or if structural repairs must be made to the deck. Please note that because the situation on your property has apparently stabilized, it is no longer considered an "emergency" under the City's critical areas ordinance, and therefore the previously issued emergency exemption no longer applies. Be aware that any future work will have to be evaluated under the City's critical areas regulations. If you believe that it is likely that you will want to pursue construction or alteration of your property, you should consider applying for applicable critical areas review(s) at the earliest available time to avoid any future delays due to a required City review. At this time the City is returning your plan submittal documents (enclosed). Some of these materials could be used in ftiture submittals should you need to pursue slope protection or slope mitigation on your property. If you have any questions please contact me directly at 425-771-0220 extension 1226. Sincerely, Jeannine L. Graf Building Official cc: Rick Powell, PE, Cornerstone Geotechnical, Inc. Will Bailey, Earthfirm, Inc. Rob Chave, Planning Manager Incorporated August 11, 1890 Sister City - Hekinan, Japan CITY OF EDMONDS 121 5TH AVENUE NORTH - EDMONDS, WA 98020 - (425) 771-0220 * FAX (425) 771-0221 Website: www.d.edmondsma.us DEVELOPMENT SERVICES DEPARTMENT Planning - Building - Engineering March 11, 2003 Robert and Nancy Lilley 19817 Maplewood Drive Edmonds, WA 98026 RE: Geotechnical Update Dear Mr. and Mrs. Lilley: GARY HAAKENSON MAYOR The purpose of this . letter is to make a second request for a geotechnical update on the monitoring program instituted by Cornerstone Geotechnical, Inc. on your property last fall. As you recall pursuant to Cornerstone letter dated October 11, 2002 a monitoring survey program was to be installed using two inclinometer casings that will monitor horizontal deflection of the slope. Also, metal rebar pins were to be driven into the ground at the top of the slope to be observed by you on a weekly basis to confirm any movement. Please direct Cornerstone to provide an update to the City and include the -status of when a written plan will be submitted that includes a schedule for implementation for temporary and permanent slope protection and slope mitigation. As a reminder, recommendations in the plan shall consider the stability of the slope and seasonal weather conditions when establishing a time schedule for installation of the stabilization measures. Once this plan is provided the City will expedite the review and approval and permit issuance. Please provide the plan by April 11, 2003. If you have any questions please contact me directly at 425-771-0220 extension 1226. Sincerely, ��W� Jeannine L. Graf Building Official cc: Rick Powell, PE, Cornerstone Geotechnical, Inc. Incorporated August 11, 1890 Sister. City - Hekinan, Japan 0 9 MEMORANDUM Date: September 10, 2001 To: Rob Chave, Planning Manager From: Star Campbell, Planning Division Subject: REQUEST FOR AN EMERGENCY EXEMPTION FROM CRITICAL AREAS REQUIREMENTS The purpose of this memo is to request an emergency exemption from critical areas requirements for 19817 Maplewood Dr. Introduction A Critical Areas Determination of Study Required has been made for the site because of the possibility of a Steep Slope Hazard Area on the site and a creek along the site's eastern boundary (See Attachment 1). The owners, Bob and Nancy Lilly, represented by Will Bailey for Earthfirm Inc. are seeking'a solution to stabilize the slope at the site. A letter requesting an exemption to Critical Areas requirements written by a Licensed Geotechnical Engineer, was submitted on September 4 th (See Attachment 2). This letter was accompanied by a Geotechnical Report for the site (See Attachment 3). The letter and the report state that revisions to the site are needed in order to stabilize the �lope. The revisions consist of a new timber retaining wall that will replace a concrete block rockery previously installed at the site (See Figure 2 of Attachment 3). Points of Consideration • A site visit was made for the Critical Areas Determination. While at the site, signs of erosion on the slope where observed. The signs of erosion are in close prbximity to the house. These were documented with photographs taken at that site visit (See Attachments 4 through 8). • The stream is located near the east property line. The stream meets the definition of a Category 3 stream. As such, it requires 25' of protection (10' buffer/ 15' building setback). The proposed revisions appear to be far enough away from the stream to be outside of this area of protection required for the stream. • A survey to show whether or not a steep slope hazard area exists on the site has not been submitted to the City. However, it appears that the location of the revisions would be within an area considered to be a steep slope hazard area. City of Edmonds cQ Planning Division The proposed revisions appear to be only those that are necessary to stabilize the slope on an emergency basis. This was stated in the letter submitted by the geotechnical engineer (Attachment 3). ECDC Chapter 20.15.B.040 allows for an exemption from the regulations of the Critical Areas Chapter for "Emergencies that threaten the public health, safety and welfare as defined in ECDC 20.110.020(D)." ECDC 20.110.020(D) defines an emergency as, "a situation in which the community services director or his/her designee determines immediate action is required to prevent or eliminate threat to health or safety or persons or property. Please review this request for an emergency exemption from critical areas regulations for the specific proposal as detailed in Attachment 3 and complete the following: Emergency Exemption Approved: P-""' (Check if applicable) Emergency Exemption Denied: (Check if applicable) Additional information will need to be reviewed before the exemption may be approved (Check if applicable) This information should consist of the following: Signed: Robert Chave, AICP, Planning Manager Date 17625-130tl Ave. NE, C102, Woodinville, WA 98072 co''r n1eirstone Phone: 425-844-1977 Geotechniccil Inc. Fax: 425-844-1987 September 3, 2002 Bob and Nancy Lilley 19817 Maplewood Drive Edmonds, Washington 98026 Geotechnical Letter — Emergency Slide Repair Lilley Residence Edmonds, Washington CG File No. 1339 Dear Mr. & Mrs. Lilley: OLP - 6,- RANp,,ij, r- "UI/ This letter presents our comments regarding the critical area requirements for the City of Edmonds. Your residence is located at 19817 Maplewood Drive in Edmonds, Washington. We have previously written a geotechnical report to improve the stability of the site, dated August 30, 2002. We understand that the City of Edmonds has evaluated. the site and concurs with our recommendation that improvements should occur on a timely basis. For this reason, the City of Edmonds has advised us that we should prepare this letter to formally request an exemption from the critical area study requirements because the slide has put the existing house at risk and requires an emergency basis to fix it prior to wet weather. The slide is down slope of your house. We have provided recommendations in our geotechnical report to improve the stability of the slope. These improvements will be directly down slope of the residence and will increase the factor of safety for deep-seated type failures. The planned improvements will consist of anchors and timber lagging. Timber lagging may extend up the slope in a crib pattern if the slope is too steep. The improvements will be on your property and will be installed to provide improvement to the stability of the slope behind the house. Therefore, we request that the critical area study requirements be exempted on this project. It is our intent only to stabilize the portions that need additional stability on an emergency basis. Geotechnical Letter — Emergency Slide Repair Lilley Residence September 3, 2002 CG File No. 13 3 9 Page 2 We appreciate the opportunity to be of service to you. If there are any questions concerning this report or if we can provide additional services, please call. Sincerely, Cornerstone Geotechnical, Inc. 31;751a-7- ' ' '9 '�� I.: 'IS I EXPIRES 08 / 16 Rick B. Powell, PE Senior Engineer JPL:RBP:nt One Copy Submitted cc: Ms. Star Campbell, Development Services Department Mr. Will Bailey, Earth Firm " Cornerstone Geotechnical, Inc. 0 CITY OF EDMONDS CRITICAL AREAS DETERMINATION Site Location: 19817 Maplewood Drive Tax Acct. Number: 5067-000-018-00-04 Determination: Study Required Determination #: CA-02-180 Applicant: Will Bailey for Bob Lilley Owner: Bob Lilley CRITICAL AREAS DETERMINATION: STUDY REQUIRED (CA-02-180) During review and inspection of the subject site, it was found that the site may contain critical areas, including a Steep Slope Hazard Area and a Stream pursuant to Chapter 20.1513 of the Edmonds Community Development Code (ECDC). STUDY REQUIREMENT — STEEP SLOPE HAZARD AREA To determine if a Steep Slope Hazard Area does exist, prior to submission of any development permit, you will be required satisfy the requirements of the Critical Areas Chapter by completing the following Steep Slope Hazard Area Delineation Requirements: A topographic survey must be completed that delineates any Steep Slope Hazard Areas prepared by a Licensed Land Surveyor. [A steep slope hazard areas is defined by the Edmonds Community Development Code as ground that rises at an inclination of 40% or greater within at least 20 feet of elevation change. In order to delineate a. steep slope hazard area, it is necessary to locate the top and toe of the slope. The inclination of the slope is established by averaging the inclination over at least 20 feet of vertical relief. A steep slope hazard area is bordered by a 50 foot widelbuffer measured from both the top and the toe of the steep slope hazard area. Adjacent to the buffer, there is a 15 feet wide building setback.] In order to complete this Study Requirement, this map must be submitted to the Planning Division for review and approval. DEVELOPMENT PROPOSALS ON A SITE WITH STEEP SLOPE HAZARD AREAS Development is restricted within the Steep Slope Hazard Area, its buffer, and/or building setback. If development must occur within these areas, the applicant may pursue certain processes provided in the Critical Areas Chapter of the Edmonds Community Development Code. The applicable process depends on the specific development proposal and site but may include one of the following: o For development proposals within the 50-foot buffer, but no closer than 10 feet from the top or toe of the slope, the 50-foot buffer requirement may be reduced to 10 feet if a study is completed by a licensed geologist or geotechnical engineer which clearly demonstrates that the proposed buffer alteration will have no adverse impact upon the site, the public or any private party. This is a process through which development could be allowed as close as 25'from the top or toe of the slope (assuming the buffer may be reduced to 10'— the 15' building setback still applies). o Development proposals closer than 25'from the top or toe of the slope may be allowed through the approval of a Steep Slope Exemption, Critical Areas Variance, or Reasonable Use Exception. These are Land Use Permits that must be obtained through the Planning Division. If you think your specific development proposal may require one of these processes, contact a Planner for more information. ATTACHMENT 1 STUDY REQUIREMENT — STREAM The site investigation has shown that the site may contain a stream near the eastern boundary of the lot. This stream fits into the definition of a Category 3 stream as defined by ECDC .20.15B.060.A.4(c). This is a stream that does not run year-round and is not used by salmonids. Based on the above finding, a Critical Areas Study is required to locate the stream on the property. Stream Delineation:, A surveyor licensed by the State of Washington must perform the TO-Ilowih g: o Physically mark the edge of the stream. I o Delineate the required buffer (refer to ECDC2.0.15B.120. (A) for the required buffer widths). o Delineate the required building setback from the buffer (required setback is 15 feet). o Create a map showing the stream, the buffer and the building setback. In order to complete this Study Requirement, this map must be submitted to the Planning Division for review and approval. NOTE: One survey may be completed that shows any steep slopes and the stream. DEVELOPMENT PROPOSALS ON A SITE WITH A STREAM Development proposals that encroach into the stream buffers or building setbacks may be allowed through the approval of certain processes. The specific process depends on.the individual site and development proposal but may include Buffer Averaging, a Critical Areas Variance, and/or a Reasonable Use Exception. If you think that you have a proposal that.may requite one of these processes, please contact a Planner for more information. i PROJECT SPECIFIC CONDITIONAL WAIVERS If the property owner wishes to apply for a specific development permit which they feel would not impact the Critical Areas located on the site, they may submit their proposal to the Planning Department for review. If the Planning Department finds that the proposed development permit will ' not adversely impact a Critical Area or its buffers, a conditional waiver may be issued on a project by project basis. EXEMPT DEVELOPMENT PROPOSALS Certain development proposals may be exempt from Critical Areas Requirements (ECDC 20.1513.040). If you think that a specific development proposal may be exempt, contact a Planner for more information. Name re Date u Cited sections of the Edmonds Community Development Code (ECDC) can be found on the City of Edmonds website, at www.ci.edmonds.wa. us. 2 0 City of Edmonds Development Services Department Planning Division Phone: 425.771.0220 Fax: 425.771.0221 The Critical Areas Checklist contained on this form is to be filled out by any person preparing a Development Permit Application for, the City of Edmonds prior to his/her submittal of the application to the City. Ile purpose of the Checklist is to enable City staff to determine whether any potential Critical Areas are, or may be, present on the subject property. The information needed to complete the Checklist should be easily available from observations of the site or data available at City Hall (Critical areas inventories, maps, or soil surveys). Date Received: B- ')--7 - o City Receipt#: ')-o LA c�, IR Critical Areas File #: 6&-0?-- 150 Critical Areas Checklist Fee: $45.00 Date Mailed to Applicant: A property owner, or his/her authorized representative, must fill out the checklist, sign and date it and submit it to the City. Ile City will review the checklist, make a precursory site visit, and make a determination of the subsequent- steps necessary to complete a development permit application. Please submit a vicinity map, along with the signed copy of this form to assist City staff in finding and locating the specific piece of property described on this form. In addition, the applicant shall include other pertinent information (e.g. site plan, topography map, etc.) or studies in conjunction with this Checklist to assistant staff in completing their preliminary assessment of the site. The undersigned applicant, and his/her/its heirs, and assigns, in consideration on the processing of the application agrees to release, indemnify, defend and hold the City of Edmonds harmless from any and all damages, including reasonable attorney's fees, arising from any action or infraction based in whole or part upon false, misleading, inaccurate or incomplete information ftirtished by the applicant, his/her/its agents o . r employees. By y signature, I cer* that the information and exhibits herewith submitted are true and correct to the best of my MY I knowledge and that I am authorized to file this application on the behalf of the owner as listed below. SIGNATURE OF APPLICANT/kGENT DATE Property Owner's Authonzadon By my signature, I cer* thai I have authorized the above Applicant/Agent to apply for the subject land use application, and grant my permission for the public officials and the staff of the City of Edmonds to enter the subject property for the purposes of inspection and pctsting 9ttendant to this application. , 1, . . SIGNATURE OF OWNER Owner/AppHeant: -Pbg Li LLe�t Name I DATE 9-A7-01 AppHcant Representadve: R. 112wi m*vLc,,--)cob Qe- ZA-Lo V-1E Lumm - 004 Qc� Street Address Street Address EOtnoka> 7 2) -0 Z (, U --) C �- K" LL city State zip city State Zip I* - Telephone: 4-Z5 G-7*1 114n Telephone: As �hB SAD Email address (optiono):. Email Address (optional): Critical Areas ChecklisLdoc/3.19-2001 480 locritical Areas Checklist CA File No: OZ' Site Information (soils/ topography/ hydrology/vegetation) - 1. Site Address/ Location: MA-1 fV^04PLZZQ00 O_IW2�0 2. Property Tax Account Number: -0Q boo -7 goo ot!a On QL-c�. rnnCa a ck:po ot g5 cr� cx4 3. Approximate Site Size (acres or square feet): 4. Is this site currently developed? A yes; — no. . If yes; how is site developed? S Nx�,Ly &wL—tw AaaAM3: Z�M-Iw_ 5. Describe the general site topography. Check all that apply. - Flat- less than 5-feet elevation change over entire site. Rolling- slopes on site generally less than 15% (a.vertical rise of 10-feet over a horizontal distance of 66-feet) Hilly: - slopes present on site of more than 15% and less than 30% ( a vertical rise of 10-feet over a horizontal distance of 33 to 66-feet). Steep: grades of greater than 30% present on site (a vertical rise of 10-feet over a horizontal distance of less than 33-feet). Other (please describe):' 6. Site contains areas of year-round standing water: Approx. Depth. 7. Site contains areas of seasonal standing water: 1�0 Approx. Depth: What season(s) of the year? 8. Site is in the floodway floodph-dn of a watercourse. 9. Site contains a creek or an area flows across the grounds surface? Flows are year-round? ows are seasonal? (What time of year? 10. Site is primarily: forested meadow shrubs mixed urban landscaped (lawnshrubs etc) 11. Obvious wetland is present on site: oo N. LU 14 LU Ll I tri A , CX: o > -j P LOT P'L/'A',M 'S C A, LIE. 20*- 0 LOT 15 MAPLFVVO0Y0 r=-5rr..T&r*4 ID IDCQ 1p IP o''P 84 41- 0 qq v ZONE SETBACKS: R OTHER HEIGHT DA' ZoneD OW. 1/4,. SEC. �l 9 T.27NE9 RA A. VA. 255 a 1%W /"07 two* 11 wl. 19509 19507 #Amurisr cmsr p1-474M3 awat" UU3 1115D c so El —IBM To RLI gig" ST: & IS.I+ 1316 741 79% 19 m x 70 197M 41" ST MAPLE if PAItIC V6 19104 mm MIS 1"14 1991, WOO .0 90 199 1"10 so A . MIS 19016 Mig :1 1. - I- q4 A. 16 *010 200 �ST 2007W P, 3T "Ms. go Sze Pal gem 103 all 20104 oc 0 VOINUMODO GCOW Tw 11009mm ._2 a.vw. .. 0 2W4 Not 2 !j teals soy I ; 11 ldw I xam sow. 20310 2mis 31EAURA ST . . . . . . . ... .. 1 JAI ton tlrsb _ST 04" . 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