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REVIEWED PLN BLD2022-0116+Geotechnical_Report+1.25.2022_9.57.12_AM+2639520RECEIVED BLD2022-0116 Jan 31 2022 CITY OF EDMONDS DEVELOPMENT SERVICES DEPARTMENT Group Northwest, Inc. September 2nd, 2021 Mr. Mike Samora 7330 —172nd St SW Edmonds, Washington Phone: (425) 220-7774 Email: MikeSamora@Hotmail.com REVIEWED BY CITY OF EDMONDS ..,.,... BUILDING DEPARTMENT.,... . Subject: Geotechnical Engineering Investigation Proposed Right -Of -Way Regrade 7330 — 172nd St SW Edmonds, Washington Dear Mr. Samora, Geotechnical Engineers, Geologists & Environmental Spccialists Reviewed by Planning - Mike Clugston, 2/15/22 G-5443 At your request, GEO Group Northwest, Inc., conducted a geotechnical engineering investigation of the above -subject property for the proposed right-of-way regrade in Edmonds, Washington. The scope of our services included review of the area geologic map; characterization of the subsurface soil and groundwater conditions encountered; preparation of hand auger soil logs (attached) and preparation of this geotechnical report. SITE CONDITIONS Site Description The project site is located in Edmonds, Washington, as illustrated in Plate I — Site Location Map. The site is rectangularly shaped and consists of 13,754 square feet (0.32 acres). The property generally slopes up to the southeast, and has an elevation high of approximately 344 feet above mean sea level above a retaining wall in the southeast corner, and has an elevation low of 318 feet at the northwest corner. The existing single-family residence and detached garage rest in the south half of the parcel. The northern half of the property is landscaped with grass, shrubbery, trees, and vegetation. It contains various tiered retaining walls which range 13705 Bel -Red Road • Bellevue, Washington 98005 Phone 425/649-8757 • Fax 425/649-8758 September 2nd, 2021 G-5443 Mr. Mike Samora 17330 — 172nd St SW, Edmonds, WA Page 2 between approximately 1 to 5 feet in vertical height. Two retaining walls are within the City of Edmonds right-of-way which borders the property to the north. The site is accessed by 172nd Street SW to the north, and is bounded by residential developed properties to the west, south, and east. Description of Proposed Project We understand that the City of Edmonds has requested the demolition of the existing retaining walls within the City right-of-way adjacent to the north property line of the above -subject residence. The lower wall ranges from approximately 2 to 4 feet in vertical height, while the upper wall ranges from approximately 0.5 to 2.5 feet in vertical height. We propose that the existing retaining walls located within the right-of-way be removed, and the right-of-way regraded to a 2H:1V (Horizontal: Vertical) inclination. We also propose that a 2-to- 3-foot-tall retaining wall be constructed with the wall toe approximately 2 to 6 inches south of the north property line of the project residence. GEOLOGIC OVERVIEW Based on a review of the geologic map for the area, as seen on Plate 2 — Geologic Map, the project site overlies Vashon Advance Outwash (Qva) deposits from the Fraser Glaciation time period. Advance outwash deposits were compacted by the overriding Puget glacial lobe after deposition and are typically dense to very dense. Advance outwash deposits typically are composed of sand with lesser amounts gravel and trace amounts of silt. SUBSURFACE INVESTIGATION On May 5th, 2021, Garrett Dean, Staff Engineering Geologist from our firm, visited the site to perform a visual reconnaissance of the property and investigate the subsurface soil conditions at the site. Three exploratory hand auger borings, HA-1 and HA-2, were drilled using a hand - operated auger. The boring locations are illustrated on Plate 3 — Site Plan, and Plate 4 — Demolition Plan and Plate 5 — Grading Plan. BLD2022-0116 Soils encountered consisted of a thin layer of topsoil to a depth of approximately 3-10 inches, RECEIVED underlain by weathered outwash consisting of medium dense to dense sand containing some 1an3120229 GEO Group Northwest, Inc. September 2nd, 2021 G-5443 Mr. Mike Samora 17330 — 172nd St SW, Edmonds, WA Page 3 subrounded gravel and trace silt. Grayish brown, dense to very dense outwash of the same composition was encountered at depths between 0.9 and 1.7 feet below the ground surface (bgs) in the borings. These soils are acceptable for wall support. We interpret the encountered soil profiles as undisturbed, native, and near the approximate original grade. For a more detailed description of the soils encountered, please refer to the hand auger boring logs in Appendix A. CONCLUSIONS AND RECOMMENDATIONS Geologic Hazard Area — Steep Slope It is our understanding that the City of Edmonds has designated the northwestern region of the property and right-of-way area a steep slope geologic hazard area. During our site reconnaissance, we observed the slope to be vegetated without signs of slope instability. In our opinion, the slope area is stable at this time. We do not anticipate slope instability to arise from the proposed development processes contingent that the recommendations provided in this report, which are conformant to the criteria contained within ECDC Chapter 23.80.070, are followed. Proposed Existing Wall Removal & Regrade We proposed to remove the existing retaining walls within the City right-of-way. Once removed, the right-of-way area should be regraded at a slope inclination of 21-1:1 V (Horizontal:Vertical) beginning at the south edge of the 172nd Ave S and continuing upslope to the south to the site's north property line. The retaining walls within the property line should remain. Locally increased inclinations near the exposed utilities near the northwest property corner can be made to accommodate access to the utilities, if needed. We estimate approximately 28.5 (+/-) cubic yards of cut material and approximately 6.7 (+/-) cubic yards of fill material. The approximate total of for the proposed regrade is 21.8 (+/-) cubic yards of material. Native site soils should be used as fill for the proposed regrade and be compacted to the specification found in this report below. No existing trees in the proposed regrade area are to be removed. For permanent erosion control, the slope should be vegetated with grass or other native vegetation. BLD2022-0116 RECEIVED Jan 31 2122 GEO Group Northwest, Inc. September 2nd, 2021 G-5443 Mr. Mike Samora 17330 — 172nd St SW, Edmonds, WA Page 4 Proposed New Retaining Wall The proposed 0.5- to 3-foot-tall retaining wall composed of 6" tall by 12" long blocks should be founded on the encountered medium dense to very dense native sandy site soils, and can be backfilled with a clean, free -draining material such as 1-1/4-inch clean, crushed rock. Since the site soils were observed to contain a high fraction of sand, the site soil may be used as wall backfill contingent that the geotechnical engineer be retained on site to determine the acceptability of soils before placement. The site soils should be placed in lifts of approximately 10 inches and compacted with a jumping jack during placement. An aerial illustration of the proposed wall can be seen on Plate 4 — Demolition Plan and Plate 5 — Grading Plan, and wall details are illustrated on Plates 6 & 7, Cross Sections A — A' and B — B', respectively. Drainage The wall requires no additional drainage considerations such that the wall is founded on and backfilled with the observed sandy site soils or clean, crushed rock. In our opinion, footing drains, such as a 4-inch minimum diameter, rigid perforated drain pipe, are not required behind the new retaining wall since the native soils in the wall proximity were observed to contain a high fraction of sand and are interpreted as free -draining material. Grading and Earthwork Erosion Control Temporary erosion and sedimentation controls (TESCs), such as silt fences, should be installed down -gradient of the areas to be disturbed to prevent sediment -laden runoff from being discharged off site. Surface runoff should not be allowed to flow over the top of slopes into excavations. During wet weather, exposed soils should be covered with plastic sheeting or straw mulch. Stockpiled soils should be covered with plastic tarps. For permanent erosion control disturbed soils should be landscaped and mulched upon completion of the site work. A construction entrance consisting of 2-4-inch crushed rock should be installed to prevent tracking onto the street or the existing driveway may be used. The construction entrance area should be cleared and grubbed prior to rock placement and we recommend underlaying the rc,ck with a woven geotextile such as Mirafi 500X, or equivalent, to provide separation beta MA2-0116 rock and subgrade soil. RECEIVED Jan 31 2122 GEO Group Northwest, Inc. September 2nd, 2021 G-5443 Mr. Mike Samora 17330 — 172nd St SW, Edmonds, WA Page 5 Excavations and Slopes Temporary excavation slopes should not be greater than the limits specified in local, state and federal government safety regulations. We recommend that temporary cuts greater than 4 feet in height be sloped at inclinations up to 1H:1V (Horizontal: Vertical) in loose to medium dense soils. Temporary excavations in the very dense advance outwash soils can be sloped near vertical under the observation of the geotechnical engineer. Permanent cut and fill slopes should be inclined no steeper than 2H:IV. Fill slopes should consist of granular material compacted to a minimum of 90 percent of the material's maximum dry density. Based on the subsurface findings, groundwater seepage is not anticipated. If water seepage or other adverse conditions are encountered, excavation should be halted, and the geotechnical engineer should be contacted to review the site conditions. LIMITATIONS The findings and recommendations stated herein are based on field observations, our experience on similar projects and our professional judgment. The recommendations presented herein are our 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 and within the project schedule and budget constraints. No warranty is expressed or implied. In the event that site conditions are found to differ from those described in this report, we should be notified so that the relevant recommendations in this report can be reevaluated and modified if appropriate. BLD2022-0116 RECEIVED Jan 31 2122 GEO Group Northwest, Inc. September 2nd, 2021 Mr. Mike Samora 17330 — 172nd St SW, Edmonds, WA CLOSING G-5443 Page 6 We appreciate the opportunity to provide you with geotechnical engineering services for this project. Please do not hesitate to contact us if you have any questions regarding this report. Sincerely, GEO Group Northwest, Inc. 'Am e�'�Z, WASy�y 201 i 4 �L[I SRO rVA L Garrett Dean, G.I.T. Staff Engineering Geologist Attachments: Plate I — Site Location Map Plate 2 — Geologic Map Plate 3 — Site Plan Plate 4 — Demolition Plan Plate 5 — Grading Plan Plate 6 — Cross Section A — A' Plate 7 — Cross Section B — B' William Chang, P.E. Principal Engineer Appendix A — USCS Soil Classification Legend & Hand Auger Boring Logs BLD2022-0116 RECEIVED Jan 31 2022 GEO Group Northwest, Inc. i ! f E drrrnn ds +■ ■ L.�. ■ r Mkikilteo I r' i I _. A- -� - —i } �6 " — — I � Picnic.. �r■hevin P:-ill Pill. P7rkland - Pal k I Source: Snohomish CountviMan. 2021 PROJECT SITE 2�- I F I 5.• Lynnwood •e f I F ter• �. #- �� I I. Mpuntlak,e ! # I i"� 1 Terr,��e Brier-- j ■ I I ■f SITE LOCATION MAP2022-0116 Group Northwest Inc. RECEIVED � PROPOSED RIGHT-OF-1niAir fci=GKAut;,,,, 2022 Geotechnical Engineers, Geologists, & 7330 - 172ND ST SW °�tiEM Fnvironmental Scientists EDMONDS, WASHINGTON SCALE NONE DATE 9/2/2021 MADE GD CHKD WC I JOB NO. G-5443 I PLATE 1 ~ dLy�r'. I •.' _ I''• :7+ , ' .'•��,x�I I,l 'va M1 I h ram' ^••,e �' ' .II •. hL� L ' I �h'.- .L + _ ''• _ -`• ' • 1. • _ `�� L' � � K_ ,-••'' ' . :1 'may — � h R � 4 — , . t . Irjr} + PROJECT SITE s' • `. ' FY I V. ti .• le II Iv'.�51 r.S. "l '�_+:. .I L. .li II I 16 • I f 'ti}... c•• �1 ''. r_..._..._ IF L �� IfP• + F �: I r ce . �i'is5...f__T I' yi.i .S" .� __._ '7•I _ 7.I'{M1 M . l�F y •k �� �-'1+� � � }Fl•I '°F�!I F .� . OVA f: - 7, I L � Source: USGS: Geologic Map of the Edmonds East and Part of the Edmonds West Quadrangles, Washington, J.P. Mimlyd, i' 863 SITE LOCATION MAP2022-0116 Group Northwest Inc. BECEIVED � PROPOSED RIGHT-OF-1niAir KtGwo►ut;,,,, 2022 Geotechnical Engineers, Geologists, & 7330 - 172ND ST SW Environmental Scientists EDMONDS, WASHINGTON SCALE NONE DATE 9/2/2021 TmADE GD CHKD WC JOB NO. G-5443 PLATE 1 Pal -FRY 1F22._ 3 F o v � g WOO _ 4J J _ _��N+70pOECN � ^� o ���°T N]`27Y,fi'E 16935 i� 0,6'WIUE + EE — — - �--- �� ---- y 0. HA e b b PM 1 1 $ Focus area as seen ` 1 o� on Plate 4 - Demolition Plan F H and Plate 5 - $� 1 HA-1 0 a 1 Grading Plan43 �. lk P L�f'W4'i Il A4F 1 S 1 NF1 i I N i'2 W E i6d.35 zar.0 n � Hand Auger Boring Number & Approximate 0 20' 40' HA-# Location Approx. Scale: 1 inch = 20' This Site Plan Adapted From Samora Limited Mapping, Mead Gilman Land Surveyors, January 13, 2019 SITE PLAN BLD2022-0116 Group Northwest, Inc. PROPOSED RIGHT-OF-WAY REGRADE RECEIVED Geotechnical Engineers, Geologists, & 7330 - 172ND ST SW Jan 312022 Environmental Scientists EDMONDS, WASHINGTON SCALE: 1" = 20' DRAWN: GD CHECKED: WC DATE: 9/2/2021 PROJECT NO.: G-5443 PLATE 3 N I I I I I PROPOSED ELEVATION EVATION CONTOURS n ?�- -&0 � X �� N. 31 / , '710 320 — �_. __-_. -- .—. / I A' N 89°36'21" W 387.31(C) 387.29(MEAS) 83.70' N M N CITY WATER CN10 MAIN (APPROX.)iA9- r 1' WIDE CONS: Psj 32y EXISTING PORTIONS BLO-GK -WALL �o OF WALLS TO BE / REMOVE % - .iA ears tube the pp � p- tv linLP g .� HA-2 PROPOSED4.41 fl�' /WALLTOE n H � .''.. JN-L(ELEV. = 325.7') �.-�n.,N.�. _ ,. r) ~i P PROPOSED sDO� WALL TOE (ELEV. = 325.0')��� O� I PROPOSED PROPOSED T ti WALL TOP WALLTOP (ELEV. = 327.5')(ELEV. = 327.6') (E I HA-1 PROPOSED WALL TOP — TOE WALL (TYP, - TOP WALL (TYP)) PROPOSED 9 / PROPOSED PROPOSED NEW WALL WALL TOP WALL TOE \(E,LEV. = 327.8') (ELEV. = 326.0') I CK C PILL R'S KA PROPOSED REGRADE PERIMETER (APPROX.) BLD2022-0116 Hand Auger Boring Number & Approximate HA-# Location 13 This Site Plan Adapted From Samora Limited Mapping, Mead Gilman Land Surveyors, January 13, 2019 = 0 DEMOLITION PLAN A • Group Northwest, Inc. PROPOSED RIGHT-OF-WAY REGRADE Geotechnical Engineers. Geologists. & Environmental Scientists 7330 -172ND ST SW RECEIVE Jan 31 2022 EDMONDS, WASHINGTON o SCALE 1" = 4' DATE 9/2/2021 MADE GD ICHKD WC IJOB No. G-5443 LPLATE 4 N I I I I I PROPOSED ELEVATION EVATION CONTOURS n ?�- -&0 s PROPOSED DO� WALL TOE (ELEV. = 325.0')��� O� rV I �� N. 31 / , '710 320 — �_. __-_. -- .—. / I A' N 89°36'21" W 387.31(C) 387.29(MEAS) 83.70' N M N CITY WATER CN10 MAIN (APPROX.)iA9- r 1' WIDE CONS: Psj 32y EXISTING PORTIONS BLO-GK -WALL �o OF WALLS TO BE / REMOVE % - .iA ears tube the pp � p- tv linLP g .� /� HA-2 PROPOSED��41 fl�' WALLTOE (ELEV. = 325.7') .-�n.,N.�. _ ,. r)~i P PROPOSED PROPOSED PROPOSED ti WALL TOP WALLTOP WALL TOE (ELEV. = 327.5')(ELEV. = 327.6') (ELEV. = 325.0') I HA-1 PROPOSED WALL TOP — TOE WALL (TYP, - TOP WALL (TYP)) 1 PROPOSED 9 / PROPOSED PROPOSED NEW WALL WALL TOP WALL TOE \(ELEV. = 327.8') (ELEV. = 326.0') I CK C PILL R'S KA PROPOSED REGRADE PERIMETER (APPROX.) BLD2022-0116 Hand Auger Boring Number & Approximate HA-# Location 13 This Site Plan Adapted From Samora Limited Mapping, Mead Gilman Land Surveyors, January 13, 2019 0 GRADING PLAN A • Group Northwest, Inc. PROPOSED RIGHT-OF-WAY REGRADE Geotechnical Engineers. Geologists. & RECEP Environmental Scientists 7330 -172ND ST SW Jan 39 21 EDMONDS, WASHINGTON ° °..-.ME, SCALE 1" = 4' DATE 9/2/2021 MADE GD CHKD WC JOB No. G-5443 PLATE 5 A �l n �--1 d CA- , 33D I PfcQoSe� Rc�a,�t�tn} I�/w�� I 5 � � M.CT�.�n��►� lnl�lls 6 6z rt/nov' A I ,.� MA-1 I \ u1 I \ I i i gt 17-1 iivy 20� ZV f BLD2022-0116 AT — IN CROSS SECTION A - A' • Group Northwest, Inc. PROPOSED RIGHT-OF-WAY REGRADE Geotechnical Engineers Geologists, 8 Environmental Scientists 7330 - 172ND ST SW RECEIVED Jan 31 2022 EDMONDS, WA SCALE 1" = 4' DATE 9/2/20211 MADE GD ICHKD WC IJOBNo. G-5443 PLATE 6 I � I Ljj 372 I H A-1 _ I 3W� I 1 yt $� �z ` ►�' zo' 7 41 z 8' 32' (feeBLD2022-0116 IN VV — CROSS SECTION B - B' • Group Northwest, Inc. PROPOSED RIGHT-OF-WAY REGRADE Geote n iEngineers, Geologists, 8 E nmental Scientists Environmental 7330 - 172 N D ST SW RECEIVED Jan 31 2022 EDMONDS, WA SCALE 1" = 4' DATE 9/2/2621 MADE GD I CHKD WC IJOB No. G-5443 IPLATE SOIL CLASSIFICATION & PENETRATION TEST DATA EXPLANATION MAJOR DIVISION CLEAN GRAVELS GRAVELS (little or no COARSE- (More Than Half fines) GRAINED SOILS Coarse Fraction is Larger Than No. 4 Sieve) DIRTY GRAVELS (with some fines) SANDS CLEAN SANDS (More Than Half More Than Half Coarse Fraction is (little or no by Weight Larger Smaller Than No. fines) Than No. 200 4 Sieve) Sieve DIRTY SANDS (with some fines) SILTS Liquid Limit (Below A -Line on < 50 % Plasticity Chart, Liquid Limit FINE-GRAINED Negligible SOILS Organics) >50% CLAYS Liquid Limit (Above A -Line on < 50 % Plasticity Chart, Liquid Limit Negligible Organics) >50% Less Than Half by Weight Larger Liquid Limit Than No.200 ORGANIC SILTS <50% Sieve (i.e., fines) &CLAYS (Below A -Line on Plasticity Chart) Liquid Limit > 50 % HIGHLY ORGANIC SOILS UNIFIED SOIL CLASSIFICATION SYSTEM (USCS) GROUP TYPICAL DESCRIPTION LABORATORY CLASSIFICATION CRITERIA SYMBOL WELL GRADED GRAVELS, GRAVEL -SAND Cu = (D60 / D10) greater than 4 GW MIXTURE, LITTLE OR NO FINES CONTENT Cc = (D30)2 / (1310 " D60) between 1 and 3 OF FINES BELOW POORLY GRADED GRAVELS, AND GRAVEL -SAND 5 % CLEAN GRAVELS NOT MEETING ABOVE GP MIXTURES LITTLE OR NO FINES REQUIREMENTS GM SILTY GRAVELS, GRAVEL -SAND -SILT MIXTURES GM: ATTERBERG LIMITS BELOW "A" LINE. CONTENT or P.I. LESS THAN 4 OF FINES EXCEEDS CLAYEY GRAVELS, GRAVEL -SAND -CLAY 12 % GC: ATTERBERG LIMITS ABOVE "A" LINE. GC MIXTURES or P.I. MORE THAN 7 WELL GRADED SANDS, GRAVELLY SANDS, Cu = (D60 / D10) greater than 6 SW LITTLE OR NO FINES CONTENT Cc = (D30)2 / (1310 " D60) between 1 and 3 OF FINES BELOW POORLY GRADED SANDS, GRAVELLY SANDS, 5 % CLEAN SANDS NOT MEETING ABOVE SP LITTLE OR NO FINES REQUIREMENTS SM SILTY SANDS, SAND -SILT MIXTURES ATTERBERG LIMITS BELOW "A" LINE with P.I. LESS THAN 4 CONTENT OF FINES EXCEEDS12% SC CLAYEY SANDS, SAND -CLAY MIXTURES ATTERBERG LIMITS ABOVE "A" LINE with P.I. MORE THAN 7 ML MH CL CH OL OH Pt SOIL PARTICLE SIZE U.S. STANDARD SIEVE FRACTION Passing Retained Sieve Sieve mm (mm) ( ) SILT / CLAY #200 0.075 SAND FINE #40 0.425 #200 0.075 MEDIUM #10 2.00 #40 0.425 COARSE #4 4.75 #10 2.00 GRAVEL FINE 0.75" 19 #4 4.75 COARSE 3" 76 0.75" 19 COBBLES 76 mm to 203 mm BOULDERS > 203 mm ROCK > 76 mm FRAGMENTS ROCK >0.76 cubic meter in volume INORGANIC SILTS, ROCK FLOUR, SANDY SILTS OF SLIGHT PLASTICITY 60 INORGANIC SILTS, MICACEOUS OR 50 - DIATOMACEOUS, FINE SANDY OR SILTY SOIL INORGANIC CLAYS OF LOW PLASTICITY, X 40 GRAVELLY, SANDY, OR SILTY CLAYS, LEAN W CLAYS Z 30 INORGANIC CLAYS OF HIGH PLASTICITY, FAT H CLAYS U 20 ORGANIC SILTS AND ORGANIC SILTY CLAYS OF LOW PLASTICITY a 10 7 ORGANIC CLAYS OF HIGH PLASTICITY 4 0 M MOONRISE slogan I WAW"15" IN11111 mm 0 10 20 30 40 50 60 70 80 90 100 PEAT AND OTHER HIGHLY ORGANIC SOILS LIQUID LIMIT (%) GENERAL GUIDANCE FOR ENGINEERING PROPERTIES OF SOILS, BASED ON STANDARD PENETRATION TEST (SPT) DATA SANDY SOILS SILTY & CLAYEY SOILS Unconfined Blow Counts Relative Friction Angle Blow Counts N Density, % x, degrees Description N Strength Clu, Description tsf 0-4 0 -15 Very Loose < 2 < 0.25 Very soft 4 - 10 15 - 35 26 - 30 Loose 2-4 0.25 - 0.50 Soft 10 - 30 35 - 65 28 - 35 Medium Dense 4-8 0.50 - 1.00 Medium Stiff 30-50 65 - 85 35 - 42 Dense 8 - 15 1.00 - 2.00 Stiff > 50 85 - 100 38 - 46 Very Dense 15 - 30 2.00 - 4.00 Very Stiff > 30 > 4.00 Hard BLD2022-0116 Group Northwest, Inc. RECE20VED Geotechnical Engineers, Geologists, & Environmental Scientists"EM 13705 Bel -Red Road Bellevue, WA 98005 Phone (425) 649-8757 E-mail: info@geogrourpnw.com PLATE Al HAND -AUGER BORING: HA-1 LOGGED BY GD LOG DATE: 5/5/2021 GROUND ELEV. 327 feet +/- DEPTH ft. USCS SOIL DESCRIPTION SAMPLE No. Water % OTHER TESTS/ COMMENTS SM Silty SAND, dark brown, medium dense, damp; Probe 7" at 0' with some subrounded gravel ----- to soil/weatheredoutwash---------------�� �----------�— S1 15.9 Probe 0.5" at 1' SW SAND, gray, dense to very dense, damp; S2 8.5 Probe 0.5" at 1.3' 2 with minor silt and some subrounded gravel (glacial outwash) S3 10.1 Probe 0.5" at 2.2' 3 Total depth = 2.2 feet No groundwater encountered. 4 5 6 7 LOGGED BY GD HAND -AUGER BORING: HA-2 LOG DATE: 5/5/2021 GROUND ELEV. 324 feet +/- DEPTH ft. USCS SOIL DESCRIPTION SAMPLE No. Water % OTHER TESTS/ COMMENTS Silty SAND, dark brown, medium dense, damp; Probe 6" at 0' \I SM with some subrounded gravel _ --- (/ topsoil) __________________________/ S1 11.4 Probe12"at1' SAND, gray, medium dense to dense, damp; 2 SW with minor silt and some subrounded gravel Probe 3" at 1.7' \ r (weathered outwash) / S2 7.2 Probe 0.5" at 2' �— --- ------------------------------ SW SAND, gray, dense to very dense, damp; 3 with minor silt and some subrounded gravel S3 8.7 Probe 0" at 2.7' (glacial outwash) 4 Total depth = 2.7 feet No groundwater encountered. 5 6 7 Group Northwest, Inc. Geotechnical Engineers, Geologists, & Environmental Scientists HAND AUGER BORING LOGS BLD2022-0116 PROPOSED RIGHT -OF INAY REGRADE 7330 - 172N D ST wRECEIVEDv ,a3, ZOZZ EDMONDS, WASHINGTON �. HAND -AUGER BORING: HA-3 LOGGED BY GD LOG DATE: 5/5/2021 GROUND ELEV. 326 feet +/- DEPTH ft. USCS SOIL DESCRIPTION SAMPLE No. Water % OTHER TESTS/ COMMENTS Silty SAND, dark brown, loose, damp; / Probe 3" at 0.0' I SM with trace subrounded gravel 1 It (topsoil/weathered outwash) Probe 12" at 10' _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _� S1 9.3 SAND, grayish -brown, medium dense to very dense, damp; SW with minor silt and some subrounded gravel 2 (glacial outwash) S2 10.2 Probe 1" at 3.7' 3 S3 7.2 Probe 0" at 2.9' Total depth = 2.9 feet No groundwater encountered. 4 5 6 7 LOGGED BY HAND -AUGER BORING: LOG DATE: GROUND ELEV. DEPTH ft. USCS SOIL DESCRIPTION SAMPLE No. Water % OTHER TESTS/ COMMENTS 1 2 3 4 5 6 7 Group Northwest, Inc. Geotechnical Engineers, Geologists, & Environmental Scientists HAND AUGER BORING LOGS BLD2022-0116 PROPOSED RIGHT -OF INAY REGRADE RECEIVED 7330 - 172ND ST SVV Jan 312022 EDMONDS, WASHINGTON �.