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224 12TH AVE N.PDF1111111111 592 224 12TH AVE N LIU & ASSOCIATES, INC. Geotechnical Engin�ng Enginwring GeohW Earth Sdence December 1, 2012 Mr Kurt Nimmergut 23128A — 76h Avenue West Edmonds, WA 98026 Dear Mr. Nimmergut: Subject: Feasibility Evaluation and Recommendations Onsite"Stormwater Disposal Nimmergut Lot 2xx — 12 th Avenue North Edmonds, Washington L&A Job No. 11-055 MRODUCTION At your request, we have completed a feasibility evaluation of onsite stormwater disposal for the subject lot, located at the above address in Edmonds, Washington. We understand that the development of a single-family residence is planned for this lot. Presented in this report are our findings, conclusion and recommendations for on onsite storinwater disposal for this residence. Previously, we performed a geotechnical investigation for this project, with our findings of the site conditions and geotechnical recommendations presented in our 07/24/2011 geotechnical report titled "Geotechnical Investigation, Single -Family Residence Building Lot, 2xx — l2th Avenue North, Edmonds, Washington." RECEIVED JAN 15 2013 DEVELOPMENT SERVICES CTR- CITY OF EDMONDS 19213 Kenlake Place NE - Kenmore, Washington 98028 Phone (426) 483-9134 - Fax (425) 486-2746 0 "TRUT FILE ""' December 1, 2012 Nimmergut Lot L&A Job No. 11-055 Page 2 SUBSURFACE EXPLORATION AND SOIL SAMPLING We explored subsurface condition of the subject lot initially on July 19, 2011, with four backhoe test pits, designated as Test Pits I through 4, with their locations shown on Plate 2. Test Pits I and 2, located on the downhill comers of the lot, had encountered an advance outwash deposit of dense, clean to slightly silty, fine to coarse sand with some gravel and occasional cobble, at 4.9 and 5.8 feet deep, respectively. We took soil samples from this deposit in these two test pits. Those samples had to be discarded after six months of no activity from the day they were obtained. When we were requested recently by you to perform an onsite stormwater disposal evaluation, soil samples would have to be obtained again in order to conduct Particle Size Distribution Tests on the samples for determine of their design infiltration rate of infiltration trenches to be used for onsite stormwater disposal. Therefore, two new backhoe test pits, designated as Test Pits 5 and 6, were excavated near Test Pits I and 2, on November 19, 2012, and soil samples were obtained from the same advance outwash deposit in these new test pits for Particle Size Distribution tests. The soil logs of the all six test pits, four old and two new, are presented on Plates 4 through 6 attached hereto. SOIL AND GROUNDWATER CONDITIONS The two new test pits, 5 and 6, were excavated to 8.5 and 9.0 feet deep, respectively. Test Pit 5 encountered a light -gray advance outwash deposit of dense, gravelly, fine to coarse sand with occasional cobble at 2.0 feet deep, which is similar to that encountered in Test Pit 1. Test Pit 6 encountered a very -dense, weakly -cemented till layer from 3.7 to 6.8 feet deep, which is underlain by a gray advance outwash deposit of dense, slightly LIU & ASSOCIATES, INC. December 1, 2012 Nimmergut Lot L&A Job No. 11 -055 Page 3 silty, fine to coarse sand with some gravel, which are similar to those encountered in Test Pit 2. Groundwater was not encountered by either Test Pit 5 or 6. DISCUSSION AND RECOAMENDATIONS Feasibility of Onsite Stormwater Disposal Based on the soil condition encountered by the test pits excavated on the lot, it is our opinion that the advance outwash deposit of clean, gravelly, fine to coarse sand with occasional cobble encountered by Test Pits I and 5 near the southwest comer of the lot should be able to support the proposed infiltration trenches to dispose stormwater onsite. Construction of infiltration trenches should be monitored by a geotechnical engineer. Particle Size Distribution Tests Two soil samples, obtained from Test Pit I at 4.0 to 6.0 feet (referred to as Soil Sample 1) and from Test Pit 2 at 7.5 to 8.5 feet (referred to as Soil Sample 2) below grade, were selected for Particle Size Distribution tests in laboratory to determine the design infiltration rate of the targeted soil deposit. The reports of these tests are presented on Plates A- I and A-2 in the attached APPENDIX. As shown in the Particle Size Distribution test reports, as presented on Plates A-1 and A-2 in the Appendix, Soil Sample I was composed of gravelly fine to coarse sand, with a clay content of 0.3%, a silt content of 2.5%, and a gravel/sand content of 97.2.0%; while Soil Sample 2 was composed of gravelly, silty, fine to coarse sand, with a clay content of 2.5%, a silt content of 24.0%, and a gravel/sand content of 73.5%. According to the LIU & ASSOCIATES, INC. December 15. 2012 Nimmergut Lot L&A Job No. 11-055 Page 4 USDA Texture Triangle Chart (IJ.S. Department of Agriculture), shown on Plate A-3 in the attached Appendix, Soil Sample I can be classified as "Sand" while Soil Sample 2 as "Loamy Sand". The reason Soil Sample 2 contained much higher silt content is because it was taken in the transition zone from the till soil layer to the advance outwash deposit. Design Infiltration Rate for Infiltration Trenches The Stormwater Management Manual for Western Washington, 2005 Edition published by Washington State Department of Ecology, was used to estimate the design infiltration rate of the target soil deposit for sizing infiltration trenches. According to the table of Recommended Infiltration Rates Based on USDA Soil Textural Classification shown on . Plate A-4, the short-term infiltration rate is estimated to be 8 iph (inches per hour) and the long-term infiltration rate 2 iph for Soil Sample 1, and 2 iph and 0.5 iph, respectively, for Soil Sample 2. As shown on Plate A-1, the 1310 size (the size of 10% passing) is 0.25 inch for Soil Sample I and 0.01 inch for Soil Sample 2. According to the table of Alternative Recommended Infiltration Rates Based On ASTM Gradation Testing presented on Plate A-5, the estimated long-term infiltration rate is, therefore, 5.0 iph for Soil Sample I and 0. 16 iph for Soil Sample 2. Based on the above, we recommend a design infiltration rate of 5.0 iph be used for the design of the infiltration trenches to be constructed in the southwest comer area of the site where Test Pits I and 5 were located. LIU & ASSOCIATES, INC. December 1, 2012 Nimmergut Lot L&A Job No. 11 -055 Page 5 Inffitration Trench Construction The trenches should be cut at least 6 inches into the underlying clean sand of advance outwash deposit To reach this target soil layer the infiltration trenches would have to be excavated at least 5.5 feet deep. The soil unit at bottom of infiltration trenches should be verified by a geotechnical engineer. The infiltration trenches should be set back at least 5 feet from property lines, at least 8 feet from nearby building foundations. The soil unit and trench cut bank stability should be verified by a geotechnical engineer during excavation. The schematic presentation of an infiltration trench with a single dispersion pipe is shown on Plate 7. The infiltration trench should be at least 24 inches wide. The schematic presentation of an infiltration trench with multiple dispersion pipes is shown on Plate 8. Multiple dispersion pipes, if used in an infiltration trench, should be placed at least 2 feet off the trench walls and spaced at no closer than 4 feet on centers. The side walls of the trenches should be lined with a layer of non -woven filter fabric, such as MULAR 140NS. The trenches are then filled with clean washed 3/4 to 1-1/2 inch gravel or crushed rock to within about 10 inches of the finish grade. The dispersion pipes should be constructed of 4-inch rigid PVC pipes and laid level in the gravel or crushed rock filled trenches at about 16 inches below the top of trenches. The top of the gravel or crushed rock fill should also be covered with the filter fabric finer. The remaining LIU & ASSOCIATES, INC. - December 1, 20-12 Nunmergut Lot L&A Job No. 11-055 Page 6 trenches should then be backfilled with onsite clean soil compacted to a non -yielding state. Gravel or crushed rock fill should be placed in lifts no more than 10 inches thick in loose state and compacted to a non -yielding state with a vibratory mechanical compactor. Stormwater captured over paved driveway should be routed into a catch basin equipped with an oil -water separator before being released into the infiltration trenches. LlMffATIONS This report has been prepared for the specific application to this project for the exclusive use by Mr. Kurt Nimmergut and his associates, representative, consultants and contractors. We recommend that this report, in its entirety, be included in the project contract documents for the information of the prospective contractors for their estimating and bidding purposes and for compliance with the recommendations in this report during construction. The conclusions and interpretations in this report, however, should not be construed as a warranty of the subsurface conditions. The scope of this study does not include services related to construction safety precautions and our recommendations are not intended to direct the contractor's methods, techniques, sequences or procedures, except as specifically described in this report for design considerations. Our recommendations and conclusions are based on the geologic and soil conditions encountered in the test pits, and our experience and engineering judgment. The conclusions and recommendations are professional opinions derived in a manner consistent with the level of care and skill ordinarily exercised by other members of the LIU & ASSOCIATES, INC. December 1, 2012 Nimmergut Lot L&A Job No. 11-055 Page 7 -anty, profession currently practicing under similar conditions in this area. No wan expressed or implied, is made. The actual subsurface conditions of the site may vary from those encountered by the test pits. The nature and extent of such variations may not become evident until construction starts. If variations appear then, we should be retained to re-evaluate the recommendations of this report, and to verify and/or modify them in writing prior to proceeding finther with the construction of the proposed development CLOSURE We are pleased to be of service to you on this project. Please feet free to contact us if you have any questions regarding this report or need further consultation. Yours very truly, n soc IN i7: C. 1. S. (Julian) Liu, Ph.D., P.E. Consulting Geotechnical Engineer Attach.: Plates 2, 4, 5, 6, 7 and 8, and Appendix LIU & ASSOCIATES.) INC. LIU & ASSOCIATES, INC. Gootmhniml F-Mineeft - Enghmdng Geobgy - Earth Sdence Ave m __:L SITE AND EXPLORATION LOCATION PLAN SINGLE-FAMILY BUILDING LOT 2XX - 12TH AVENUE NORTH EDMONDS, WASHINGTON !OB NO. ll::55-5 1 DATE 7/20Q�Ll I I PLATE-, TEST PIT NO. 3 Logged By.- JSL Date: 7119/2011 Ground El. Depth ft. USCS CLASS- Soil Description Sample No. W % Other Test SM Brown, loose. organic� silty fine SAND, with fine roots. slightly -'-rqqiS-L - - - - - - - - - - - - - - - - - — - - Sm - - - - - - - - - - Light -gray, dense to ver"ense. silty fine SAND, tam to some 2 gravel, slightly moist (fresh VASHON TILL) 3 4 5 6- 7 8 Test pit terminated at 6.5 ft; groundwater not encountered. 9- 10 TEST PIT NO. 4 Logged By- JSL Date. 7119/2011 Ground El. Depth ft. USCS CLASS. Soil Description Sample No. W % OHM Test SM Dark -brown, loose. organir, silty fine SAND, with fine roots. - - - - - - - - - - - - - - - - - - - - - --- Light-brown, dense, silly fine SAND, slight moist 2 3 ------------------------------------------- sm Light -gray. dense to very -dense, silty, fine to medium SAND, trace 4 to some gravel, occasional cobble. slightly moist (fresh VASHON TILL) 6 ---------- ------------------------------- 7 SP Gray, dense, slightly silty, fine to medium SAND, traim gravel, slightly moist (fresh ADVANCE OUTWASH) a- 9 Test pit terminated at 7.5 ft; groundwater not encountered. LIU & ASSOCIATES, INC. Geotechnical Engineering - Engineering Geology - Earth Sclenoe � TEST PIT LOGS SINGLE-FAMILY BUILDING LOT 2XX - 12TH AVENUE NORTH EDMONDS, WASHINGTON ' JOB NO. 11-055 1 DATE 7/19/20111 PLATE APPENDIX Particle Size Distribution Test Report Single -Family Building Lot 2xx — 12'h Avenue North Edmonds, Washington LIU & ASSOCIATES., INC. November 28, 2012 HWA Project No. 2012-025-23 Task 17 Table I — Summary of Sieve Analysis Test Results M 0 r J: ti TP-5, S-1 4-6 ft Olive brown poorly gmded SAND with gravel (SP) 5 24.5 62.4 15 0.3 0,25 TP-6, S-2 7.5-8.5 ft Olive brown silty SAND with gravel (SM) 8 22.4 51.2 24.0 2.5 0.01 Lab Report 2 e%, 0-- HWA GeoSciences Inc. FLIATE A - I- min GRAVEL SAND SILT Coarse Fine Coarse Medium Fine MEN MIR I in oil lllin I ilillmmh,, 11 1 11111111 HER moillills I I , OMEN oil,[ N sollillil§Ellll I 0 1111 WINNER I u n .11110m--illilli I'M 11111111 SYMBOL SAMPLE DEPTH (ft) CLASSIFICA11ON OF SOIL- ASTM 02487 Group Symbol and Name MC LL PL p, Gravel % Send CAI Fines OA * TP-5 S-1 4.0-6.0 (SP) Olive brown, poorly graded SAND with gravel 34.8 62.4 2.8 * TP-6 'S.2 7.5-8.5 (SMI) Olive brown, silty SAND with gravel 22.4 51.2 26.5 PARTICLE -SIZE ANALYSIS Laboratory Testing for Liu and Associates OF SOILS HWAGEOSCENCHINC Nimmergut Lot METHOD ASTM D422 PROJECT NO.: 2012-025 T1700 FIGURE.' HWAGR8Z 2012�=T170D.GPJ 11=112 P L-A-Te A--Z Tblxtural -TrIangle - U.S.D.A. IM cloy- 80 20 TO Cla 30 60 40 so si so Cl 40 Sandv By 7Y, illy Go Sandy . lay oam lay loam loam TO Loam 10 0 WE, IQ0X Cond 0 20 '10 go TO 60 so --R*mw Percent - 00% ent Shaded area is applicable for design Of infiltration BMPs Ngure 3.27 USDA Textural Triangle Source: U.S. Department of Agriculture 3-74 Volume III - HYdMI091C Anaiy_&� and —Flow coWi-,�I-gm—p— - .s February 200,5 FLAT& A- 3 for homogeneous soils. These rates not consider the e ts of site f Fec V, ! variability and long-term clogging due to siltation and biomass buildup in the infiltration facility. Table 3.7 — Recommended Infiltration Rates- basW on USDA Soil Te)xdt Classification. Estimated Long - *Short -Term Term (Design) Luffitration Correction Inilltration Rate Rate (Whr) Factor, CF. Onihr) Clean sandy gravels and 20 2 10 gravelly sands (Le., 90% of the total soil sample is retained in the#] 0 sieve) Sand 8 4 2*** Loamy Sand 2 4 0.5 Sandy Loam 1 4 025 Loam - 1 0.13 *P--11MV1AOf1V "Not recommended for uwhncnt Refer to SSC-4 and SSC-6 for treatment acceptability criteria Based on experience with long-term full-scale infiltration pond Performance, Ecology's Technical Advisory Committee (TAC) recommends that the short-term infiltration rates be reduced as shown in Table 3.7, dividing by a correction factor of 2 to 4 1 depending on the soil textural classification- The correction factors provided in Table 3.7 represent an average degree of long-term facility maintenance, TSS reduction through pretreatment and site variability in the subsurface conditions- -Mese conditions might include deposits of ancient landslide debris, buried stream channels, lateral grain size variability, and other factors that affect homogeneity) - These correction factors could be reduced, subject to the approval of the local jurisdiction, under the following conditions: 9 For sites with little soil variability, * Where there will be a high degree of long-term facility maintenance, a Where specific, reliable pretreatment is employed to reduce TSS entering the infiltration facility ID 110 MW shall a correction factor less than 2,0 be used. 3-76 VOIUMe III — HYdrologic Ana"is and . Flow Control BMps February 2005 PLI-\Te- A-4 CII(in 'Eactors higher am those provided in Table 3.7 should be considered for situations where long-term MainWaanCe will be difficult to implement, where little Or no preftitment is anticipate4 or where sit e- conditions am highly variable or uncertain.: These dMations require the use-bf best professional judgment by the site engineer and the approval of the local jurisdiction. An operation and Mainteanc. plan and . financial bonding plan may be required by the local jurisdiction. 2.A As an alternative to Table 3.7, recent studies by Massmann and Butchart (2000) were: used to develop the correlation Provided in Table 3.8. These studies compare infiltration measurements from fiIII-scale infiltration facilities to soil gradation data developed using the ASTM proced I urc (ASTM D422). The primary source of the data used by Massmarm and Butchart was from vviltsie (1998), who included limited ifiltration studies only on Thurston County sites- HOwCvcT; Massmann and Butchart also included limited data from King and Clark County sites in their analysis. Ibis table provides recommended long-term infiltration rates that have' been correlated to soil gradation ParaMeMrs using the ASTM soil gradation procedure_ Table 3.8 can be used to estimate long-term design infiltration rates directly from soil gradation da ta, subject to the approval of the local jurisdiction. As is true of Table 3.7, the long-term rates provided in Table 3-8 rePresent average conditions regarding site variability, the degree of long-term maintenance and Pretreatment for ISS control. The long-term infiltration rates in Table 3.8 may need to be decreased if the site is highly variable, or if maintenance and influent characteristics are not well controlled. The data that forms the basis for Table 3.8 was from soils that would be classified as sands or sandy gravels. No data was available for finer soils at the time the table was developed. Therefore, Table 3.8 should not be used for soils with a dio size (10% passing the size listed) less than 0.05 mm (US. Standard Sieve). Table 3.8 — Alternative Recommended Infiltration Rates on Gradation Testinct. Dio Size from ASTrd D422 Soil Estimated Lang-Terro (Design) Gradation Test (mm) Infiltration Rate (inibr) ?: 0.4 .9..- 0-3 6.5* 022 3-5* 0.1 2 t� OJ)5 0.9 0 Refff to SSC-4 md SSC�j-j(;7M=n=a=cPMbiY CFUUia FebnIaPJ 2005 "ImO "I — HYdrOlogic Analksis and Flow Control BMp, 3-77 P -TF LA , A-5 Z 6 C; M 0 rp Or Z fn ; 0 > c cn 0, > > :E < k > m cn Z 3: C m r z r Z 0 Z 0 z 0 r c r 10 CLSA� N-51're, (L, P I L-� Oil Ile ot, .!5SDIMeAT 6NTRO4. 20 v -51 lo?6 IT pvc ripa OZ - P.:.ASIQ (Kr=&PF:bg -0 0 . ; > u-, fZ4)qOF4-- LU Lj' c LJ14 , OP4 L yo (PV c- -n 4; H-rL I S FA6 K (e- CL81s-,�A 391-ro lY:z"'W,6,,lHe�D4ZAV6L GoTToml-rp,a�cH M 1 r4 14T.0 6LFW� 5AO)"�oiLS o4- a -�b pe� rA rA C- 0 a) z 0 04 z z 6 C) 0 -4 K , mr- m 0— m z z —a 0 C/) > < k M > M a) C: C/) Z Z 6) z -� 0 Z 0 -0 Z M 0 ;o 0 z m co CD MUL-ripLa 0 1 L - WA TaP- u 0 f-e�-Rr-, Ta�p Fcr- M\/F,- P\/C- TIGHT I L;14V-- W/,\y gv�,40pF-04 LY) -CILC--At4 S4 ;.JV�' �RAVr,-L- I OR CAU5,H5-P'K0eK r-ILL- r6arromITI:�5NcH G"MIP4, I t� TO C-L-eAV4 'SA�40Y 4�,01 LS LIU & ASSOCIATES, INC. Geotechnical Engineering Engineering Geology July 24, 2011 Mr. Kurt Nimmergut 23128A — 760Ayenue West Edmonds, WA 98026 Dear Mr. Nimmergut: Subject: Geotechnical Investigation Single -Family Residence Building Lot 2xx — 12th Avenue North Edmonds, Washington L&A Job No. 11 -055 I TO-11116"Tem Earth Science We have completed a geotechnical investigation for the subject single-family building lot, located at the above address in Edmonds, Washington. The general location of the site is shown on Plate I - Vicinity Map. We understand that your proposed development for the subject lot is to build a single-family residence, although architectural design plans for the residence is yet to be completed. The purpose of this investigation - is to explore subsurface conditions of the lot and evaluate site stability and potential geologic hazards of the lot for the proposed development. For this investigation four test pits have been excavated on the lot to explore subsurface conditions of the lot. Presented in this report are our findings of the site conditions, conclusion of site stability and some general geotechnical recommendations for the proposed development of the lot. RECEIVED 19213 Kenlake Place NE - Kenmore, Washington 98028 JAN 15 2013 Phone (425) 483-91134 - Fax (426) 486-2746 DEVELOPMENT SERVICES CTR. C17Y OF EDMONDS 421 S_ July 24, 2011 Mr. Kurt Nimmergut L&A Job No. 11 -05 5 Page 2 SCOPE OF SERVICES The achieve the -above purpose of this study, our scope of services comprise specifically the following: I Review the geologic and soil conditions at the lot based on a published geologic map. 2. Explore the subsurface conditions of the lot with backhoe test pits. 3. Evaluate site stability and potential geologic hazards of the lot and provide general geologic recommendations for the proposed development of the lot based on subsurface conditions encountered by the test pits. 4. Prepare a wTitten report to present our findings, conclusion, and recommendations. SITE CONDITIONS Surface Condition For our use in this investigation, you provided us with a topographic survey plan of the subject lot. 'Me lot is situated on the mid -slope of a moderate to steep, west -declining hillside. -We understand the subject lot is about,�/5 feet wide by about 135 feet deep. � 10, According to the topographic survey plan of the lot, as shown on Plate 2, the terrain within the lot generally slopes down westerly at about 7 to 15 percent grade for approximately the eastern two fifths of the lot, then steepens to about 17 to 23 percent grade for the remaining lot. The lot is currently vacant and undeveloped. It is covered with grass and occasional shrubs, and dotted by scattered young ornamental trees. LIU & ASSOCIATES, INC. M July 24, 2011 Mr. Kurt Nimmergut L&A Job No. 11-055 Page 3 Geologic Setting The Geologic Mgp of the Edmonds East and Part of the Edmonds West Quadrangles, Washingion by James P. Minard, published by U. S. Geological Survey in 1983, was referenced for the geologic and soil conditions at the residence site. According to this publication, the surficial soil unit at and in the vicinity of the subject lot is mapped as an Advance Outwash (Qva) soil unit. The advance outv.--ash soil unit is composed of stratified sand and gravel with very minor amount of silt and clay, deposited by the meltwater of advancing glacial ice of the last glacier. Due to their generally granular composition,g§�Aqyanc� outwash de osits are of moderately high permeability and drains fairly well. The advance outwash deposits had been glacially overridden and are generally dense to very dense in their natural, undisturbed state, except the top 2 to 4 feet of soils which are normally weathered to a loose to medium -dense state. The advance outwash deposits can stand in steep cuts or natural slopes for extended period when undisturbed. Where exposed on slopes with poor vegetation cover and subjected to storm runoff or groundwater seepage, the advance outwash deposits can be gradually eroded and may slough and redeposit to a flatter inclination. The underlying fresh advance outwash deposits in their native, undisturbed state can provide good foundation support with little settlement expected for light to moderately heavy structures. LIU & ASSOCIATES., INC. July 24, 2011 Mr. Kurt Nimmergut L&A Job No. 11-055 Page 4 Soil Condition Subsurface conditions of the subject lot were explored with four test pits. These test pits were excavated on July 19, 2011, with a rubber -tired backhoe to depths of 6.5 to 8.5 feet. The approximate locations of the test pits are shown on Plate 2 - Site and Exploration Location Plan. The test pits were located with either a tape measure or by visual reference to existing topographic features in the field and on the topographic survey map, and their locations should be considered only accurate to the measuring method used. A geotechnical engineer from our office was present during subsurface exploration, who examined the soil and geologic conditions encountered and completed logs -of test pits. Soil samples obtained from each soil layer in the test pits were visually classified in general accordance with United Soil Classification System, a copy of which is presented on Plate 3. Detailed descriptions of soils encountered during site exploration are presented in test pit logs on Plates 4 and 5. Test Pits 1. 2 and 3 were located near the southwest, northwest and northeast comers of the lot, respectively; while Test Pit 4 was located in the southeast quadrant of the lot. Test Pits 2, 3 and 4 encountered a laver of fresh Vashon till of light -gray, dense to ver�- dense, silty, fine to medium sand with a trace to some gravel and occasional cobble, with the surface of this layer at about 0.7 to 3.0 feet below the existing ground surface. This till deposit is overlain by a layer of weathered soil of brown to light -brown, medium - dense to dense, silty fine sand. The till deposit was not encountered by Test Pit Instead, a fresh advance outwash deposit of gray, dense, gravelly, medium to coarse sa�,d LIU & ASSOCIATES., INC. July 24, 2011 Mr. Kurt Nimmergut L&A Job No. 11 -055 Page 5 was encountered by this test pit at about 4.8 feet below existing grade. This advance outwash deposit is overlain by layers of light -brown to bro-%vn-gray, medium -dense to dense, gravelly, slightly silty to silty,- fine sand with occasional cobble, totaling 4.8 feet thick. The fresh advance ouuvash deposit was also encountered in Test Pit 2 after the till layer was punctured through. The advance outwash in Test Pit 2 was composed of gray', dense, slightly silty, fine to medium sand. with a trace of gravel. The Vashon till deposit encountered in Test Pits 2, 3 and 4 was plowed directly und�r glacial ice during the most recent glacial period as the glacier advanced over an eroded, irregular surface of older formations and sediments. It is composed of a mixture of unsorted clay, silt, sand, gravel, and scattered cobbles and boulders. The Vashon till soils over the top two to four feet are normally weathered to a medium -dense state, and i's moderately permeable and compressible. The underlying fresh till soils are very dense, and are commonly referred to as "hard pan". The fresh till soils are practicalW impervious to stormwater infiltration. The fresh till soils possess the strength of low- _gT4de concrete and can stand in steep natural slopes or man -make cuts for a long period. If remained undisturbed and well -drained, the fresh till soils can provide excellent I foundation support to structures with little settlement expected. Groundwater Condition Groundwater was not encountered by any of the four test pits excavated on the site. The fresh till soil underlying the site at shallow depth is of extremely low permeability and would perch stormwater infiltrating into the more permeable surficial weathered soils. LIU & ASSOCIATES, INC. I July 24, 2011 Mr. Kurt Nimmergut L&A Job No. 11 -055 Page 6 The amount of and the depth to this near -surface, perched groundwater would fluctuate seasonally, depending on precipitation, surface runoff, ground vegetation cover, site utilization, and other factors. This near -surface perched groundwater may dry uo completely- during the dryer summer months and accumulate and rise in the wet winte,t months. The fresh advance outwash deposit of gravelly medium to coarse sand and its overlying weathered soil are of high permeability and would allow stormwater to seep through easily. Therefore, the impact of groundwater on the construction of the proposed new residence should be minimal. CONCLUSION AND RECOMMENDATIONS General The design plans of the proposed residence to be constructed on the subject lot are yet to be completed. Therefore, only geotechnical recommendations of general nature for the development of the lot are presented in this report. We will be glad to provide project specific recommendations after we are provided with a set of design plans of tl�e residence. Site Stability The lot is underlain by dense to very -dense, fresh, Vashon till and advance oumas,h deposits of high to very -high shear strength. These soils are of high resistance again�t slope failure. Therefore, the lot is suitable for development of the proposed residence and should be quite stable, provided the general recommendations presented in this report and project specific recommendations to be furnished in future geotechnical engineering study LIU & ASSOCIATES.) INC. q July 24, 2011 Mr. Kurt Nimmergut L&A Job No. 11 -055 Page 7 are implemented and observed during and following completion of construction of the proposed residence. Geologic Hazards and Mitigation The fresh till soil underlying most of the lot at very shallow depth is of extremely low permeability and would perch stormwater infiltrating into the more permeable surficiAl soils. There is an remote chance that in wet winter months seepage of shallow perched groundwater may result in erosion of surficial weaker soils if vegetation cover is devoid. Progressive erosion may lead to shallow, skin -type mudflows. To mitigate such erosion haza d. excavation, grading and foundation construction work of the new residence should be carried out and completed in the dryer period from April 1 through October 3 1'. A silt fence should be installed along the downhill boundaries of the site to minimize transport of sediment onto neighboring properties or the street. The bottom of the filter cloth of the silt fences should be anchored in a trench filled with onsite soils. Vegetation outside of construction limits should be preserved and maintained. Interceptor trench drains should be installed on the uphill sides of construction areas, as required, to intercept and safety drain away surface runoff and near -surface perched groundwater. Unpaved exposed finished ground within the lot resulted from construction activitie's should be re -seeded and re -vegetated as soon as possible. Exposed ground and seeded areas should be covered with clear plastic sheets, as required, for erosion protection during construction. LIU & ASSOCIATES, INC. 9 July 24, 2011 Mr. Kurt Nimmergut L&A Job No. 11 -055 Page 8 Concentrated stormwater should not be discharged uncontrolled onto the ground within or adjacent to the lot. Stormwater over impervious surfaces, such as driveway and roofs of the new residence, should be captured by underground drain line system connected to roof downspouts. Water collected -by such drain line system should be tightlined to discharge into a storm sewer if one is available nearby. Otherwise, collected stormwater should be disposed through a suitable stormwater disposal facilities, such as infiltration trenches. If these recommendations are implemented, the erosion hazard of the property should be minimal. The lot is underlain by dense to very -dense, fresh, Vashon till and advance outwash deposits of high to very -high shear strength. Therefore, it is unlikely for deep-seated landslides to occur on the lot. With the competent soils underlying the lot and the lack of continuous extensive groundwater table at shallow depth beneath the lot, it is also unlikely for seismic hazards, such as soil lateral spreading, liquefaction, etc., to occur on the lot. Excavation Slopes Under no circumstance should excavation slopes be steeper than the limits specified by local, state and federal safety regulations if workers have to perform construction work in excavated areas. Unsupported temporary cuts greater than 4 feet in height should be n o steeper than I H: IV in surficial weathered soil, may be vertical in the underlying dense very -dense, fresh till provided that the overall depth of excavation does not exceed 12 LIU & ASSOCIATES, INC. 11 July 24, 2011 Mr. Kurt Nimmergut L&A Job No. 11-055 Page 9 feet, and . should be no steeper than 1/2H: I V in the dense, fresh, advance outwash soil underlying the till deposit. Excavation into the slope may be required for the construction of the new residence. If there is not sufficient space between the proposed building and the lot boundaries for sloped cut at the above recommended temporary cut slopes, excavation shoring would be required. We will be glad to provide excavation shoring recommendations when the project specifics of the residence are made available to us. Building Foundations Conventional footing foundations may be used to support the proposed residence. The footing foundations should be constructed on or into the undisturbed, dense to very -dense, fresh, till and/or advance outwash soils. For design of footing foundations of the residence, including dead and live loads, an allowable soil bearing pressure no greater - _- --- ---- than 3,000 psf may be used, -A one-third increase in this allowable soil bearing pressure may be used when considering short-term, transitory, wind or seismic loads. Drainage Control Building footprint excavation for the new residence, if encountering groundwater 'seepage, should have the bottom of excavation sloped and ditches excavated along bases of the cut banks to direct collected groundwater into sump pits from which water can be pumped out. A layer of 2-inch crushed rock should be placed over footing bearing subgrade soils, as required, to protect the soils from disturbance by construction traffic. LIU & ASSOCIATES, INC. p July 24, 2011 Mr. Kurt Nimmergut L&A Job No. 11 -055 Page 10 Storm runoff over impervious surfaces, such as roofs and paved driveway, should be collected by underground drain line systems connected to downspouts and by catch basins installed in the driveway. A drain line consisting of perforated, rigid, PVC drain pipe, at least 4 inches in diameter, should be installed at a few inches below bottom of basement walls to intercept and drain away groundwater flowing towards the walls. The drain lines should have sufficient slope (0.5 percent minimum) to generate flow by gravity, and water collected in the drain lines should be tightlined to discharge into a storm sewer or a suitable stormwater disposal facility. The drain lines should be completely embedded in washed gravel wrapped in a layer of non -woven filter fabric sock, such as 140N by Mirafi Inc., or approved equal. A vertical drainage blanket at least 12 inches thick, consisting of clean, 3/4 to 1-1/2-inch, washed gravel or crushed rock, should be placed against the walls. Stormwat.er and-. Fzroupdw.aper collected by the above drain line systems should be tightlined to discharge into a storm sewer or a suitable stormwater disposal facilities, such as infiltration trenches. LIMITATIONS This report has been prepared for the specific application to the subject project for the exclusive use by Mr. and Mrs. Nimmergut and their representatives, consultants and contractors- The conclusions and interpretations in this report, however, should not be construed as a warranty of the subsurface conditions. The scope of this study does not include services related to construction safety precautions and our recommendations are not intended to direct the contractor's methods, techniques, sequences or procedures, except as specifically described in this report for design considerations. LIU & ASSOCIATES, INC. July 24, 2011 Mr. Kurt Nimmergut L&A Job No. 11-055 Page I I The conclusion and general recommendations in this report are based on the geologic and soil conditions encountered in the test pits excavated on the lot, and our experience and engineering judgment. The conclusions and recommendations are professional opinions derived in' a manner consistent with the level of care and skill ordinarily exercised by other members of the profession currently practicing under similar conditions in this area. No warranty, expressed or implied, is made. The actual subsurface conditions of the site may vary from those encountered by the test pits. The nature and extent of such variations may not become evident until construction starts. If variations appear then, we should be retained to re-evaluate the recommendations of this report, and to verify or modify them in writing prior to proceeding further with the construction of the new residence. CLOSURE We are pleased to be of service to you on this project. Please feel free tocontact us if you have any questions regarding this report or need further consultation. Five plates attached Yours very truly, LIU SSOCIATF INC J. S. (Julian) Liu, Ph.D., P.E. Consulting Geotechnical Engineer LIU & ASSOCIATES.) INC. jE v S! rn cu AV 5 rq -,w RD , `1 1 ­ - - �� .:-, . j�� ;1, � I 3 t1l, 11 4A 11 on s , 1%, s 4, c p, b COO) AV s CA 5TH A AV s 40' *Ponf 6TH 2 to I 61H AV G) �Ull AV S 6T H s ";"A' T Um A I Ilk" m to AT15 . 0 . I !� P. $1 ­ Im Ono 7 V am AV L SrA VIS k to I AIMA Pt t w �TH AV m M 9TH 41A. AV ILI v ICU- Film; 98TH Fl, 'A p 7 ... �_S_L te 9:: P, �4 AV Ll) PL 98TIl -7 _-T 6_55 _H 1071 �jv 0 PL t t ILI' 9�Hll AV W lea F JIM z - .. ie q AV L� J, 0 �i' E , -1 01.4pic] 1v It _J!� . -.1ill : AV U) 5111 PL W i-;- 95TH PL W I I'll It Pl, N b 12lil AV 931W 6 '93RD 94111 Vj* ;9 w AV I ."", ­ - - 0 m -fi73 ­UL !r4 � NN 1 .1. ; . _T 11 - I w JPTH PLI z < 92ND 'lip C) > ��7=AV W 9. 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F33RD E�, AV W AV pt T! 82NO AV, �W PL W AV AV - - 2 0� MO AV, W m Pl, w p w �j T, 0-0 OIST 12 AV W" 80TIl L W". �11T L-N A _LCT-1-LL w S T AV p w 7,� AV t 1� UNIFIED SOIL CLASSIFICATION SYSTEM MAJOR DIVISIONS GROUP GROUP NAME SYMBOL GRAVEL CLEAN GW WELL -GRADED GRAVEL, FINE TO COARSE GRAVEL I COARSE- MORE THAN 50% OF GRAVEL GP POORLY -GRADED GRAVEL GRAVEL WITH GM SILTY GRAVEL GRAINED COARSE FRACTION SOILS RETAINED ON NO. 4 SIEVE FINES I GC CLAYEY GRAVEL SAND CLEAN SW WELL -GRADED SAND, FINE TO COARSE SAND MORE THAN 50% MORE THAN 5D% OF SAND SP POORLY -GRADED SAND SAND WITH SM SILTY SAND RETAINED ON THE COARSE FRACTION NO. 200 SIEVE PASSING NO. 4 SIEVE FINES' SC CLAYEY SAND FINE- SILT AND CLAY INORGANIC ML SILT CL CLAY GRAINED LIQUID LIMIT SOILS LESS THAN 50% ORGANIC OL ORGANIC SILT, ORGANIC CLAY SILTY AND CLAY INORGANIC MH SILT OF HIGH PLASTICITY, ELASTIC SILT MORE THAN 50% CH CLAY OF HIGH PLASTICITY, FAT CLAY PASSING ON THE LIQUID LIMIT NO, 200 SIEVE 5D% OR MORE ORGANIC OH ORGANIC SILT, ORGANIC SILT HIGHLY ORGANIC SOILS PT PEAT AND OTHER HIGHLY ORGANIC SOILS NOTES: SOIL MOISTURE MODIFIERS: 1. FIELD CLASSIFICATION IS BASED ON VISUAL EXAMINATION DRY - ABSENCE OF MOISTURE, DUSTY, DRY TO OF SOIL IN GENERAL ACCORDANCE WITH ASTM D2488-83. THETOUCH 2. SOIL CLASSIFICATION USING LABORATORY TESTS IS BASED SLIGHTLY MOIST - TRACE MOISTURE, NOT DUSTY ON ASTM D2487-83. MOIST - DAMP, BUT NO VISIBLE WATER 3. DESCRIPTIONS OF SOIL DENSITY OR CONSISTENCY ARE VERY MOIST - VERY DAMP, MOISTURE FELT TO THE TOUCH BASED ON INTERPRETATION OF BLOW -COUNT DATA, VISUAL WET - VISIBLE FREE WATER OR SATURATED, APPEARANCE OF SOILS, AND/OR TEST DATA. USUALLY SOIL IS OBTAINED FROM BELOW WATER TABLE LIU & ASSOCIATES, INC. UNIFIED SOIL CLASSIFICATION SYSTEM Geotechnical Engineering - Engineering Geology - Earth Science PLATE 3 t� LIU & ASSOCIATES, INC. Geotechnical Engineering - Engineering Goo" - Earth Science zzZz SITE AND EXPLORATION LOCATION PLAN SINGLE-FAMILY BUILDING LOT 2XX - 12TH AVENUE NORTH EDMONDS, WASHINGTON 001 TEST PIT NO. 1 Logged By: JSL Date: 7/19/2011 r_1 Depth USCS CLASS. Soil Descripfion Sampt If No. L 11 Other Test SM Light -brown, medium -dense, gravelly, silty, fine SAND, with fine roots, dry 2 3 ........................................... 4 SID Brown -gray, dense, gravelly, slightly silty, fine to medium SAND, occasional cobble, dry 5 -------------- -------------------------- SW Gray, dense, gravelly, medium to 4��S7AND, occasional 6 cobble, slight moist (fresh ADVANCE OUTWASH) 7 8 9 Test pit terminated at 8.0 ft; groundwater not encountered. 10 TEST PIT NO. 2 Logged By: JSL Date: 7/19/2011 Ground El. Depth USCS CLASS. Soil Description Sample No. W— % Other Test SM Light -brown, medium -dense, silty fine SAND, with fine roots, dry 2 7 ------------------------------------------ - SM Light -brown to light -gray, very -dense, silty fine SAND, some gravel, 3 dry (fresh VASHON TILL) 4 5 6 7 ------------------------------ SID ---- Gray, dense, slightly silty, fine to medium SAND. trace gravel, 8 slightly moist (fresh ADVANCE OUTWASH) 9 Test pit terminated at 8.5 ft; groundwater not encountered. 10 LIU & ASSOCIATES, INC. Geotechnical Engineering - Engineering Geology - Earth Science TEST PIT NO. 3 Logged By: JSL Date: 7/19/2011 Ground El. Depth ft. LISCS CLASS. Soil Descripbon Sample No. W % Other Test Sm Brown, loose, organic, silty fine SAND, with fine roots, slightly '_rnsc LISL Sm - - - - - - - - - - - - - - - - - - Light -gray, dense to very -dense, silty fine S;�N_5,_trac­e -to-so-m-e 2 gravel, slightly moist (fresh VASHON TILL) 3 4 5 6 7 8 Test pit terminated at 6.5 ft; groundwater not encountered. 9 to — TEST PIT NO. 4 Logged By: JSL Date: 7/19/2011 Ground El. Depth ft. USCS CLASS. Soil Descripbon Sample No. w % Other Test Sm Dark -brown, loose, organic, silty fine SAND, with fine roots, Aly nqj:Lt -_S1jgL L - - - - - - - - - - - - - - - - - - - -- Light-brown, dense, silty fine SAND, slight moist 2 _'N r Cig�t� n;e c�v;iWenVe, silty, fine to medium SAND, trace ay, 4 to some gravel, occasional cobble, slightly moist (t�tsh V�S�!ON TILL) 5 6 ----------- ------------------------------ 7 SID Gray, dense, slightly sitty,fine to medium SAND, trace gravel, slightly moist (fresh ADVANCE OUTWASH) 9 Test pit terminated at 7.5 ft; groundwater not encountered. 10 LIU & ASSOCIATES, INC. Geotechnical Engineering - Engineering Geology - Earth science TEST PIT LOGS SINGLE-FAMILY BUILDING LOT 2XX - 12TH AVENUE NORTH EDMONDS, WASHINGTON JOB NO. 11-055 .1 DATE 1/19/20111 PLATE 4 2129 77" Section'2. All lots herein not specifically noted shall have so height restrictions -except those common to the City of Edmonds standard building code and restrictions. The f011Owing'lots shall have height, I(. restrictions as follows: The roof ridge line or any-pait of the house* - garage or other Permitted building, except the chimney Or fireplace to� thereof, shall not extend above the stated height limit. All measure- ments shall be made from the top of the concrete street curb at the location noted for each lot: ­17 feet maximum height from 135*feet south Lot 12 V'! Of the 'nbrtheim!-most corn 13--21 er facing east on Highland Drive Jr `-Lot feet maximum height from the southeast corner of lot facing east o' n Highland Drive Loi;U4-:�ihr;u 18--17 feet Maximum height from center of each lot as facing -east Of'Hiqhland Drive. Lot'19.-'thru 23--27=feet maximum height as facing west on 12th Avenue West. Lot 24 thru 297-17 feet maxd:mum height from center of each'lot facing on Emerald Hills.Drive J,.ot 30 & 33-- 21 feet maximum height from center of each lot facing dn Emerald Hills Drive. Lot 36--16 feet maximum height from center-of.lot f' Emerald Hills Drive. acing on Lot 37--17 feet maximum height from center of lot facing on 12th Ave. West lot 40--le feet maximum height from center of lot facing on 1 1 2th Ave. West lot 41--21 feet ma . ximum height from.center \ of lot facing on Emerald Hills Drive. Lot 49--16 feet maximum height from center of lot facing on Skyli Drive. ne Lot 50 thru 54-- 17 feet maximum height from center of lot f* on Skyline Drive. acing ARTICLE XI 14—I.P.RESERVATION OF TREES ------ ..... trees on --individual lots D, . e i I— shall bg.limited to the area :.. :. ings,*patlOs and driveways are the va :trees must'first have the appro to be constructed.. - Any val of the'Architectural Control'C Uttee as hereinbefo-re stated in Article Omm -VII. ARTICLE X11 COMMON AREA MAINTENANCE: Section 1. A:11 common area streets are to be maintained by the Association through the Board of Trustees to At least equal Edmonds City design standards applicable to public streets of substantially the same width. Section 2. The association through the Board of Trustees shall preserve and. -maintain all Common areas in the natural setting and'in close conformity to . the condition at the time Declarant conveyed the location _hrithin- thirty. (.-w) dzAys after said plan and specifications have been submitted to it, approval will not be S' will be doeried to have been fully COmplied with. rcquired and the Article ARTICLE Vill USE RE-STRICTIOSS f Section 1. All Lots shall-5c known and described as residential Lots except said Co-nmon Area. No structures or buildings of any kind!-. shall be erected, altered, placed or permitted to remain on any rcsid- ential building lot Other than one detached Si"gle-fa-mily dwelling for single-family occupancy only not to exceed two stories in height and a private garage for not more than three cars, one of which may be for a boat or a trailer. A swimming pOO1 With appurtenant structures are also 8110%4ecl. Section-2. No building shall be located nearer to t . he front line of' t h e' ro- 't or nearer to the side street line than the building setback l7ines if-:shown'on tile recorded plat. In any event, no building of any kind sliall'be -located on any residential lot nearer than t,j. the front lot line, nor itearer than twent -fi ve(25) fe irty (30) feet to street 11ne, and no 6ttilding shall y et to any side be located nearer than twenty-five (25) feet tO tile rear lot line except rear yard fit:ured from center line of open. -space or easement in no case less than ten (10) feet with the exception of a detached garage. 3o. bui'lJing shall be locate� nearer than seven and one hal F (7 112) feet of the s'idc lot line. A detached gar . age may he located withill j*ive rcet of tile rear lot line, except where rear lot line abuts a street, ill 'which case the front yard setback of thirty (30) feet or -nore would prevail unless otberwis6 approved by said Arch- itectural Control C'onrlittcc. '11ardship cases may receive approval of variance by the ARchitcctural Control cortnittee sub" the Ci ty 0 f E Jcct to approval by - Section 3. - No dwelling sh.111 be permitted O'n any Lot at a cost of less than 000O."g) Cxclllsivc of land, based up -on the cost levels prevailing on the (late these restrictions are recorded, it being the intention and purpose or these restrictions to assure t,iat all dwellin . gs shall be of quality of wo,rkmanship and materials substaltially the same or better than that which can be produced on the date these restrictions are recorded at tile -minimum cost stated herein For tile nillimum permitted.' d.wellilig size.' The. ground floor area of th e main structure, exclusive open porclies, carports *and garage not be less than "ll undred square 'feet for the ground fl�' t tire I Ve sh. o'ne -siory. oor of a dwelling of more Section 4. T) Wre Zro� -NO alli-m-11S. livestock or Poultry of any kind shall b' eTg e rais r kept on any lot, except that clogs cats or other house' i1old pets may bekept in compliance # and provided that they are not kop With existing laws and regulations t, bred or maintained for any commercia.' purpose. The foregoing is intended also to exclude tile keep . ng of any' �pets such'as cats, dogs or birds in numbers or under conditio'ns reason- ably ohj.ectionabl . e-in the Closely built -tip residential commullity. Sect-'O."S- VO building or structure sh embrac all* be moved onto any land in said subdivision from 'any land Outside of said subdivision. No ;trailers Shall be maintained on any, building site as a residence. ',No building of any kind shall he erected or maintained oil a building site prior to the erection of a dwelling house thereon, e . xcept that a garage or other small -building of permarient, constru .�tion may be erected for a private greenhouse or for the' -storing of tools and other articles.. b:ut PLANNINGDATA SINGLE FAMILY RESIDENTIAL F=ILE I Name: Date: Site Address: TaxParcel 6()Lp36o000'?300 Project Description: Plan Check #: Reduced Site Plan Provided: S NO) Zoning: Map Page: I Corner Lot: (YES Flag Lot: (YES '(D Critical Areas Determination CKA2p)lo ot � R- Study Required — -e-y-o St\ov\ %-1P-7CW'VJ El waiver SEPA Determination: 497-Exempt Needed (for over 500 cubic yards of grading) 0 Fee 0 Checklist 0 APO List with notarized form Required Setbacks '?,-r Stree 3 Side: -7 Side: � S -7/,2- Rear: 1 )LS- Actual Setbacks --[�ear Street: Side: q( 9 Side: El Detached Structures: ER Rockeries: R5 Fences/Trellises: El Bay Windows/Projecting Modulation: C1 Stairs/Deck: Height Datum Point: Datum Elevation: to(� 5-( ' "0 Maximum Height Allowed: Actual Height: Other Parking Required: Parking Provided: )L- Lot Area: 00 Maximum Lot Coverage: 35% Proposed: Lot Coverage Calculations: ADU Created: (YES Subdivision: r, Legal Nonconforming Land Use Determination Issued: (YES Comments Plan Review By: Planning Data Form 07-1+09.doc PLANNING DATA STREETFIL _�E]j Plan Review By: Planning Data Form 07-14-09.doc City of Edmonds Critical Area Notice of Decision Applicant: "W%W-eya, V+ Property Owner: V^ W%,e V� Q, Critical Area File 'J 0 C> Pen -nit Number: Site Location: Parcel Number: C>09�3Do66001-30 0 Project Description: Conditional Waiver. No critical area report is required for the project described above. There will be no alteration of a -Critical Area or its required buffer. 2. The proposal. is an �Ilowed activity pursuant to ECDC 23.40.220, 23.50.220, and/or 23.80.040. 3. The proposal is exempt pursuant to ECDC 23.40.230. Erosion Hazard. Project is within erosion hazard area. Applicant must prepare an erosion and sediment control plan in compliance with ECDC 18.30. Fj Critical Area Report Require d. The proposed project is within a critical area and/or a critical area buffer and a critical area report is required. A critical area report has been submitted and evaluated for compliance with the following criteria- pursuant.to ECDC 23.40,160: I The proposal minimizes the impact on critical areas in accordance with ECDC 23.40.120, Mitigation sequencing; 2. The proposal does not pose an unreasonable, threat to the public health, safety, or welfare on or 6ff the development proposal site; 3. The proposal is consistent with the general purposes of this title and the public interest; 4. Any alterations permitted to the critical area are mitigated in accordance w,ith ECDC 23.40. 110, Mitigation requirements. 5. The proposal protects the critical area'fimctions and values consistent with the best available science and results in no net loss.of critical functions and values; and 6. The proposal is consistent with other applicable regulations and standards. F� Unfavorable Critical Area Decision. The proposed project is not exempt or does not adequately .mi . tiga�� its impacts on critical areas and/or does not comply with the criteria in ECDC 23.40.160 and 'the provisions of the City of Edmonds critical area regulations. See attached findings of noncompliance. eFavorable Critical Area Decision. The proposed project as described above and as shown on the attached site plan meets or is exempt from the criteria in' ECDC 23.40.160, Review Criteria, and complies with the applicable provisions of the City of Edmonds critical area regulations.. Any subsequent changes to the proposal shall void this decision pending re -review of the proposal. Conditions. Critical Area specific condition(s) have been applied to the permit number referenced above. See referenced permit nu bber for s cific condition(s). 'or s II'c Y\ Iteview-er S gnature Date Appeals: Any decision to approve, condition, or deny a development proposal or other.activity based on the requirements of critical area regulations may be appealed according to, and as part of, the appeal procedure, if any, for the permit or approval involved. Revise.d 12/16/2010 1E-A-D,Z-b C— TOP OF CURB ELEV. = 98.60' (254.W) — Co � WATER METER EXISTING CONCRETE UTILITY CONNECTIONS SIDEWALK SEE DRAINAGE EXISTING UTILITY PLAN FOR Al I CONCRETE PTILITY(OWIECTDISIS CURB 21 zr- A SSCO 0 0 SITE BENCH ELEV-= I W FOR C OFEDMONDS Ell BUILDING HEIGHT CALCULATION (ACTUAL ELEV. 256.15) DRIVEWAY CURBCUT 0 %.. PER CITY OF 0 4. EDMONDS �Jorffi STANDARDS J I J TOP OF CURB ELEV. = 104.46 (260.46) CENTER OF RIGHT - WAY 11 6 Site Plan III -011 11 29 On 0 " JPP LOVE4D' PLANNING 2_ 1_1 2- I.L- r-6- SIDEYARD SIDEYARD SETBACK IN EMERALD HILLS IS 7-6" NEW 6 HIGH CEDAR FENCE SETBACK AS APPROVED BY THE CITY OF EDMONDS UTILITY METERS @ HIS WALL 7 PROPERTY LINE S89d53-00-W 13 01 ot 10 (257),� �WMLA + '(2831 SCAPE BLOCK RETAINING, 127 56'- 0" NEW LAND 01 WALLS. SEE CIVIL GRADING PLAN 8 Tco -E 0- DINT A 8 ; MERALD ALL CONTO tu UR LINES� HILLS UTILITY ELEV. 113' SHOWN ARE EXISTING C--�-rASEMENT FOR HEIGHT CONDITIONS. E 1,,'�ROPO4D�ONCRETE IN AT :25'- 0 ALCULATION SEE CIVIL SITE GRADING DRIVEWAY OINT B PLAN FOR PROPOSEDI LU ELEV. 122- CONTOURS&ALL 11 1 F— ?= 1:26CITYOF 7, I FOR HEIGHT GRADING INFORMATION & C> EDMONDSFRONT /CALCULATION REQUIREMENTS C� 01� Lu CL SETBA C K 0. TRENCH DRAIN @ THIS AREA. SEE UJI Z-F IL GRADING & UTILITY zi f 317 —RAi EMERALD. LAN HILLS PLAT,' SETBACK POI� D LU a- 0 - LE 12.25' MASONRY OR HEIG /POINT C BLOCK a_ CALCU [ON EV. 120 PAVERS @ 1.1 ULT I El ELEC. VAULT Hall ------- - ---- -----NEW-6`HI(- JX-CED' F H L I 1" 0 '14C \V1Y 1<1:1 Q1V 'Q1V h� 4 ,1k 4' -cV 1: b CONCRETE RETAINING WALL. SEE CIVIL GRADING PLAN IMPERVIOUS SURFACE CALCS. PROPOSED BUILDING ROOF ODTLINE: 2496 S.F. PROPOSED DRIVEWAY AREA = 1703 S.F.* PROPOSED PATIO & WALKWAYS = 622 S.F.* (PORTIONS OF WALK, PATIO, & DRIVEWAY AREAS UNDER ROOF OVERHANG ARE INCLUDED IN BUILDING ROOF OUTLINE AREA ABOVE) TOTAL IMPERVIOUS SURFACE AREA = 4794 S.F. PLAN REVIEWER NOTE THIS DRAWING IS NOT A SITE GRADING PLAN. REFER TO CAAL ENGINEERS GRADING PLAN FOR ALL PROPOSED SITE GRADING AND SITE WORK FOR H IG PATIO & EXISTING RETAINING WALLS TO BE CALCU ON WALKWAY REMOVED OR COVERED W/ FILL. SEE CIVIL SITE GRADING PLAN LANDSCAPE AREA A :,PATIO LANDSCAPE PAVERS Ca --PATIO & WALKWAY — .�-' �- 36- HIGH GUARDRAIL / FEN ' PROPERTY LINE N89d53'00"E 135.00' LANDSCAPE BLOCK RETAINING I WALLS. SEE CIVIL GRADING PLAN HEIGHT CALCULATION A=+113' J0 B=+122' C = +1 2(Y 3ri D = + 112.25' -Q 6 AVG. GRADE= 116.81' ACTUAL = 128.25' MAXIMUM = 141.81' LOT COVERAGE LOT SIZE = 11.002 S.F. BLDG. FTPRINT. = 1862 S.F. % COVERAGE = 17% LOT SLOPE: 16% i SLOPES FROM EAST DOWN TO WEST I 26 REARI SETBACK - --- -------- SIDEYARD SETBACK IN EMERALD HILLS IS r-V AS APPROVED BY THE CITY OF EDMONDS GRADE ELEVATIONS / CONTOUR LINES CITY OF EDMONDS REQUIRES BUILDING' HEIGHT CALCULATIONS FROM AN ESTABLISHED BENCHMARK NOTED AS ELEVATION IOV-0". ALL GRADES & CONTOUR LINES HAVE TWO NUMBERS: 1 PER CITY OF EDMONDS REQUIREMENTS AND 1 FOR ACTUACGRADE ABOVE SEA LEVEL -- NEW 6 HIGH CEDAR FENCE 128! (2841 126'(282') +125'(282) NEW 6' HIGH CEDAR FENCE EM--EMLDHILLS HEIGHT CALCULATION MIDPOINT OF CURB = 257.53! MAX. HT. ALLOWED = CURB HEIGHT @ MIDPOINT PLUS 2r MAX. ROOF RIDGE HEIGHT = 284.53' PROPOSED ROOF RIDGE HEIGHT = 284.2V This set of drawings is being issued as a Progress or Permit Set of Drawings and is subject to change and adding of additional information and Carl J. Colsbti - Eileen & Kurt NitntnergLit drawings as required by review of the Building Department in the jurisdiction where this project is located. DO NOT USE M DRAWING POR CONMI=ON UNIESS TFHS DRAWING HAS A BUILDWG DERARD4ENT -AppgoyEp- ATchitect P1JLC 224 12th Ave. W STAMP APPIJED BY THE BUILDING DMAKTALENT UPON COMILMON OF THE PERMIT REVIEW PROCESS, 23623 20th Ave. W, BothellW;'A 98021 Edmonds, WA 98020 Do not use this drawing for Bidding or Estimating Purposes unless authorized by Client During Construction Phase, the Clients General 425-806-3703 Contractor (Builder) of Developer shall be responsible for ensu* that all Construction Personnel of the General Contractor and all Subcontractors are supplied with alljoro and most current documents. CarlColsonArchite—c— Commercial & Residential Architecture SITE DATA PROJECT ADDRESS: 224 12th Ave. W Edmonds, WA 98020 PROJECT OWNERS: Kurt & Eileen Nimmergut 23128-A 76th Edmonds, WA 98026 ASSESSORS PARCEL NUMBER: 00423000002300 LEGAL DESCRIPTION: LOT 23, EMERALD HILLS, ACCORDING TO THE PLAT THEREOF, RECORDED IN VOLUME 31 OF PLATS, PAGES 46-49, RECORDS OF SNOHOMISH COUNTY, WASHINGTON; SITUATE IN THE COUNTY OF SNOHOMISH, STATE OF WASHINGTON. SUBJECT TO CONDITIONS, RESTRICTIONS, RESERVATION AND EASEMENTS OF RECORD IF ANY. LOT SIZE: 11,002 SQ FT LOT COVERAGE OFNEW STRUCTURE: 1850 S.F. = 16.81/6 (35% ALLOWED) SEE SITE PLAN FOR ADDITIONAL INFORMATION STRUCTURE HEIGHT: PROPOSED STRUCTURE HEIGHT 1 V ALLOWED STRUCTURE HEIGHT = 25'-W (DUE TO SLOPED SITE CONDITIONS AND PLAT HEIGHT RESTRICTIONS, HOUSE IS BUILT AS A ONE STORY FLAT ROOFED HOUSE W/ DAYLIGHT BASEMENT. SEE SITE PLAN FOR HEIGHT CALCULATIONS) PROJECT ZONING: RS-12 PROJECT DESCRIPTION: CONSTRUCTION OF A NEW SINGLE FAMILY RESIDENCE WATTACHED.GARAGE SITE WORK: SITE WORK PLANNED IS FOR EXCAVATION FOR NEW FOOTINGS, SITE REGRADING, AND CONSTRUCTION OF NEW DRIVEWAY. SEE CIVIL DRAWINGS FOR SITE GRADING PLAN SITE DESIGN DATA SEISMIC: SEISMIC.DESIGN CATEGORY: D SITE CLASS: C SEISMIC USE GROUP: If WIND: BASIC WIND SPEED: 85 MPH WIND EXPOSURE: 8 BUILDING CATEGORY: 11 SNOW LOADS 25 PSF DESIGN LOADS PER CHAPTER 3 OF 2009 INTERNATIONAL RESIDENTIAL CODE SOIL BEARING CAPACITY ASSUMED 2000 PSF. Nimmergut Residence 224 12th Ave. W FIECEIVE Edmonds,, WA 98020 11 JAN 15 2013 OFEIYMONDS SITE PLAN