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DNS_RESUB 1-Geotech ReportNO November 2, 2021 Project No. 20210191EO01 Susan Stark 133 Sunset Avenue North Edmonds, Washington 98020 a s s o c i a t e d earth sciences i n c o r p o r a t e d Subject: Limited Geotechnical Engineering Study - Settlement Mitigation Stark Residence 133 Sunset Avenue North Edmonds, Washington Dear Ms. Stark: Associated Earth Sciences, Inc. (AESI) is pleased to present our evaluation of building settlement cause and geotechnical recommendations for settlement mitigation. Our general understanding of the project is based on discussions with you, a site visit, previous experience on similar projects, and our knowledge of geologic conditions in the vicinity. This letter -report has been prepared for the exclusive use of Ms. Susan Stark and her agents, for specific application to this project. Within the limitations of scope and schedule, our services have been performed in accordance with generally accepted local geotechnical engineering practices in effect at the time our letter -report was prepared. No other warranty, express or implied, is made. Our work was performed in general accordance with our proposal, dated July 14, 2021. PROJECT BACKGROUND As shown on Figure 1, "Vicinity Map," the site consists of the 0.11-acre residential parcel located at 133 Sunset Avenue North in Edmonds, Washington (Snohomish County Parcel 00434401300500). The site contains an existing two -level building with daylight basement used as a single-family residence and law office reportedly built in 1968. The building is constructed on a west -facing slope toward Puget Sound. The property is bordered to the north and south by multifamily residences, to the west by railroad tracks along the Puget Sound shoreline, and to the east by Sunset Avenue North. We understand that settlement of the building has occurred primarily in the west -central portion and that magnitude is estimated to range from 1 to 2 inches. Problems with closing interior doors on the west side of the building began about 7 years ago and cracks have developed in the central brick fireplace and upper level drywall. Kirkland I Tacoma I Mount Vernon 425-827-7701 1 www.aesgeo.com Stark Residence Foundation Repair Limited Geotechnical Engineering Study Edmonds, Washington Settlement Mitigation We understand that you would like to determine the cause of building settlement and evaluate options for mitigation of the settlement since the long-term plans for the property include an eventual transfer of ownership to you. SUBSURFACE EXPLORATION Subsurface conditions at the site are based on one exploration boring which was advanced on August 23, 2021. The boring was completed using a limited -access, rubber -tracked, drilling rig advancing a 6-inch outside -diameter, hollow -stem auger tool. During the drilling process, samples were obtained at generally 5-foot intervals. The boring was continuously observed and logged by an engineering geologist from our firm. The exploration log presented in the Appendix is based on observed drilling action and samples collected. Disturbed but representative samples were obtained by using the Standard Penetration Test (SPT) procedure in accordance with ASTM International (ASTM) D-1586. This test and sampling method consists of driving a standard, 2-inch outside -diameter, split -barrel sampler a distance of 18 inches into the soil with a 140-pound hammer free -falling a distance of 30 inches. The number of blows for each 6-inch interval is recorded, and the number of blows required to drive the sampler the final 12 inches is known as the Standard Penetration Resistance ("N") or blow count. If a total of 50 blows are recorded at or before the end of one 6-inch interval, the blow count is recorded as the number of blows for the corresponding number of inches of penetration. The resistance, or N-value, provides a measure of the relative density of granular soils or the relative consistency of cohesive soils. These values are plotted on the exploration boring log. The samples obtained from the split -barrel sampler were classified in the field and representative portions placed in watertight containers. The samples were then transported to our laboratory for further visual classification and geotechnical laboratory testing, as necessary. The various types of materials and sediments encountered in the exploration, as well as the depths where characteristics of these materials changed, are indicated on the attached exploration log. The depths indicated on the log where conditions changed may represent gradational variations between sediment types. The approximate location of the exploration boring is shown on the attached Figure 2. November 2, 2021 ASSOCIATED EARTH SCIENCES, INC. JG/ms-20210191EO01-002 Page 2 Stark Residence Foundation Repair Limited Geotechnical Engineering Study Edmonds, Washington Settlement Mitigation SUBSURFACE CONDITIONS Topsoil At the location of exploration boring E13-1, we encountered a surficial organic -rich topsoil horizon with an approximate thickness of 8 inches. Due to its high organic content, topsoil is not suitable for foundation support. Fill Underlying the surficial topsoil horizon, our exploration encountered approximately 7 feet of very loose to loose, moist, light brown, fine sand, with variable silt and gravel content and trace organics and trace debris present. These materials are interpreted as fill soils placed during original site development. Fill is also expected to be found around buried utilities, foundation/wall backfill areas, and beneath landscape improvements. Due to their very loose condition, these fill soils are not suitable for foundation support. Recent Beach/Marsh Deposits Underlying the fill, exploration boring E13-1 encountered very loose, gray, fine sand interbedded with medium stiff, fine, sandy silt with occasional peat interbeds. This material is interpreted as recent beach and marsh sediments deposited in a low -energy environment after the most recent glaciation of the Puget Lowlands approximately 12,500 years ago. Recent beach/marsh deposits consist of detrital material, such as silt, sand, gravel, and organics, which have been transported and deposited by flowing water or deposited along the shores of Puget Sound. Portions of these sediments contained enough organic material to be classified as peat, which is indicative of a wetland depositional environment. The thickness of the recent beach and marsh deposits was approximately 12 feet at the location of E13-1. Due to its generally soft/loose condition and lenses of organics, these deposits pose a high risk of settlement under foundation loads. For this reason, the recent beach and marsh deposits are not recommended for direct structural support. Whidbey Formation Underlying the recent beach/marsh deposits at a depth of 20 feet below the existing ground surface, our exploration encountered very dense, gray, massive, fine to medium sand with trace silt content. These sediments are interpreted as belonging to the Whidbey Formation which consists of non -glacial deposits placed prior to the most recent glaciation of the Puget Lowland that were subsequently compacted by the weight of the overlying glacial ice during the Vashon State of the Fraser Glaciation. Whidbey Formation sediments are suitable for foundation support. November 2, 2021 ASSOCIATED EARTH SCIENCES, INC. JG/ms-20210191EO01-002 Page 3 Stark Residence Foundation Repair Limited Geotechnical Engineering Study Edmonds, Washington Settlement Mitigation Pre -Whidbey Glacial Till Underlying the Whidbey Formation sediments at a depth of approximately 23 feet below existing ground surface and extending past the explored depth of 30.5 feet, our exploration encountered unsorted, gray, very dense, silty, fine sand with variable gravel content. We interpret these sediments as pre -Whidbey -age glacial till. This glacial till was deposited directly from basal, debris -laden glacial ice during a glaciation prior to the most recent glacial advance during the Vashon Stade of the Fraser Glaciation. The high relative density characteristic of pre -Whidbey glacial till is due to its consolidation by the massive weight of the glacial ice from which it was deposited and by subsequent glaciations. Pre -Whidbey glacial till is suitable for support of structural loads. Published Geologic Map Review Review of the published geologic map Geologic Map of the Edmonds East and Part of the Edmonds West Quadrangles, Washington, U.S. Geological Survey (USGS), Miscellaneous Field Studies Map MF-1541 by J.P. Minard (1983) indicates that the subject site is underlain by Modified Land and Whidbey Formation with Marsh Deposits mapped nearby. Our interpretation of geologic conditions at the site is in general agreement with the referenced geologic map. Published Soils Map Review Review of the U.S. Department of Agriculture Soil Conservation Service, now referred to as Natural Resources Conservation Service (NRCS), Web Soil Survey indicates that the subject site is underlain by Urban Land. This mapped soil type consists of areas that are covered by streets, buildings, parking lots, and other structures that obscure or alter the soils so that identification is not possible. Due to the fill soils encountered, our interpretation of geologic conditions at the site is in general agreement with the published soils mapping. Hydrology At the time of our exploration, groundwater seepage was encountered from approximately 8 to 15 feet below existing ground surface within the fill soils and upper, sandy portion of the recent beach/marsh deposits. We interpret this groundwater as perched on top of the lower, recent beach/marsh silt. Perched groundwater, also known as "interflow," occurs when vertical infiltration is impeded by less -permeable soils, such as silty beach/marsh deposits, and horizontal migration occurs. It should be noted that groundwater levels below the site fluctuate in response to such factors as tides, changes in season, precipitation, and on- and off -site land use. Our field exploration was conducted in mid -September when groundwater levels are typically nearing their seasonal low. November 2, 2021 ASSOCIATED EARTH SCIENCES, INC. JG/ms-20210191EO01-002 Page 4 Stark Residence Foundation Repair Limited Geotechnical Engineering Study Edmonds, Washington Settlement Mitigation SETTLEMENT EVALUATION Based upon the conditions encountered in our exploration boring, it appears that very loose fill and organic -rich recent beach/marsh deposits are present beneath the west side of the existing residence. A suitable foundation bearing stratum is present at least 20 feet below existing grade. We understand that settlement has occurred primarily in the west -central portion of the building and that magnitude is estimated to range from 1 to 2 inches. Problems with closing interior doors on the west side of the building began about 7 years ago, and cracks have developed in the central brick fireplace and upper level drywall. Review of the City of Edmonds GIS Map Portal shows permit and construction documents relating to this property. These City of Edmonds documents show an "Application for Side Sewer Permit" that was stamped approved on April 25, 1968. This document shows a hand -drawn site plan describing the property, the building, and the location of the side sewer exiting at the west - central side of the building and continuing southwest to the sewer main just outside the west property line. Other documents describe a water meter along Sunset Avenue that was damaged by city workers resulting in a significant leak and causing pavement subsidence and cracking in 1984. In 1999, plans were submitted to the City to replace a portion of the east foundation wall, with construction completed in 2000. From discussions with you, the building is reportedly supported on piles. However, we could not confirm the presence of piles during our review of City documents or during our site visits. If present, the pile depth is unknown, and the building settlement suggests that the pile foundation is not performing as designed. It is our opinion that the settlement observed below the west -central portion of the existing residence is likely due to the presence of fill soils and organic -rich beach/marsh sediments underlying the property. These sediments are in a very loose to loose condition and contain organic material that consolidates over a long period of time as a result of the load induced from the fill soils above. Additional consolidation within the loose fill and the organic -rich recent beach/marsh deposits and settlement of the ground surface beneath and around the building will likely continue. In addition, during a strong seismic event there is the potential of settlement due to the liquefaction of these loose deposits. If a pile foundation is present, the consolidation of the beach/marsh sediments can also induce increased loads on the piles in the form of "downdrag" from the skin friction on the piles. It is not known whether the original design took these additional loads into account and it is unlikely that liquefaction was considered given the age of the building. November 2, 2021 ASSOCIATED EARTH SCIENCES, INC. JG/ms-20210191EO01-002 Page 5 Stark Residence Foundation Repair Limited Geotechnical Engineering Study Edmonds, Washington Settlement Mitigation MITIGATION RECOMMENDATIONS The site is underlain by approximately 20 feet of generally loose/medium stiff sediments that are subject to consolidation and settlement under foundation loads and pose a risk of liquefaction during a strong seismic event. To mitigate existing settlement and possible future settlement due to liquefaction, we recommend underpinning the existing foundations along the west side of the building with small -diameter pipe piles that fully penetrate the fill and recent beach/marsh deposits and are driven to refusal in the underlying, glacially consolidated, Whidbey Formation or pre -Whidbey glacial till sediments. While we feel confident that underpinning will mitigate future settlement along the west side of the building, it is possible that additional settlement will occur in other parts of the structure with time or during a strong seismic event. With installation of recommended deep foundations embedded into very dense glacial soils along the west side of the building, there is still a risk that differential settlement could occur between this location and other portions of the building where foundations may be inadequate or supported on compressible/liquefiable soils. Small -Diameter Pipe Piles Allowable axial capacities for small -diameter driven pipe piles are provided below in Table 1. Table 1 Small -Diameter Pipe Pile Recommendations Nominal Pipe Diameter Minimum Wall Thickness Minimum Hammer Size Allowable Axial Capacity Driving Time (seconds/inch) 3-inch Schedule 40 400 pounds 12 kips 30 4-inch Schedule 40 1,100 pounds 17 kips 10 In order for the stated pile capacities to apply, the pipe piles should be driven to refusal, which is defined as less than 1 inch of penetration during the specified period of continuous driving. They should also completely penetrate the fill and recent beach/marsh sediments. No lateral capacity would be provided by vertically installed pipe piles. Lateral capacity could be attained through the use of battered piles or passive resistance over the buried portions of the grade beams. An allowable passive equivalent fluid of 200 pounds per cubic foot (pcf) may be used for foundation design. For the recommended passive equivalent fluid to apply, the grade beams must be backfilled with structural fill compacted to at least 95 percent of the modified Proctor maximum dry density (ASTM D-1557). Piles may be battered up to 15 degrees to develop additional lateral capacity. Lateral capacity of battered piles may be taken as the horizontal component of the axial pile load. Battered piles inclined up to 15 degrees should be designed November 2, 2021 ASSOCIATED EARTH SCIENCES, INC. JG/ms-20210191EO01-002 Page 6 Stark Residence Foundation Repair Limited Geotechnical Engineering Study Edmonds, Washington Settlement Mitigation with an allowable axial compressive capacity equal to that used for vertical piles. Pile spacing, locations, splicing details, foundation connection details, grade beam design, and any other structural design recommendations should be determined by a structural engineer. Installation of the pipe piles should be observed by an AESI representative to verify that the refusal and embedment criteria are met and that materials, equipment, and procedures conform with our recommendations. This may also be required by the City of Edmonds. For pipe piles larger than 2 inches in diameter, we recommend that load testing in accordance with the ASTM Quick Load Test (ASTM D-1143) be conducted to 200 percent of the allowable pile capacity on a minimum of 3 percent (1 pile minimum, 5 piles maximum) of the piles. Existing Sewer and Drainage System Audit Due to the proximity of the building settlement and the location of the side sewer, we recommend that a video survey of the existing side sewer be conducted by an experienced contractor. A broken or damaged side sewer discharging into the loose fill soils and recent beach/marsh deposits could cause additional subsistence. We do not have any information pertaining to the discharge locations of roof runoff and foundation drains. We recommend an audit of the existing drainage system be performed by an experienced contractor. The collection and discharge points of drains for existing impervious surfaces should be identified and the "water -tightness" of these drains evaluated. If leaks are suspected, these drains should be repaired or replaced. If the drains discharge next to the building, these should be extended to an area downslope of the building or be connected to the existing drainage system. Under no circumstances should stormwater be discharged on or above the on -site slopes or next to the existing building. PROJECT DESIGN AND CONSTRUCTION MONITORING We are available to provide additional geotechnical engineering upon request and monitoring services during construction. The integrity of the earthwork and foundations depends on proper site preparation and construction procedures. In addition, engineering decisions may have to be made in the field in the event that variations in subsurface conditions become apparent. Construction monitoring services are not part of this current scope of work. November 2, 2021 ASSOCIATED EARTH SCIENCES, INC. JG/ms-20210191EO01-002 Page 7 Stark Residence Foundation Repair Limited Geotechnical Engineering Study Edmonds, Washington Settlement Mitigation CLOSURE We appreciate the opportunity to be of service to you on this project. Should you have any questions regarding this report or other geotechnical aspects of the project, please call us at your earliest convenience. Sincerely, ASSOCIATED EARTH SCIENCES, INC. Kirkland, Washington oshua S. P. Greer, G.I.T. Senior Staff Geologist A. WAS�rr, `R-70 rru Stephen A. Siebert, P.E. Associate Geotechnical Engineer Attachments: Figure 1: Vicinity Map Figure 2: Existing Site and Exploration Plan Appendix: Exploration Log November 2, 2021 ASSOCIATED EARTH SCIENCES, INC. JG/ms-20210191EO01-002 Page 8 M,gI4 f � i � � — _ f �� I tit Y• I�. { � LJt � I�- a �•;1, it � I- ?�•� yL r * r a 524 lie _ 1 ' ��• _ T1 i SITE _• -l; ' r D - . S5 � a . � '' T —� + \ ti � 5•`�M1M1 - �'�M1. ems'_:_ 5 4'- eA Ll TinL� a s s o c i a t e d N earth Sciences A ja i In c❑ r p❑ r a t e d 0 2000 VICINITY MAP Feet DATA SOURCES/ REFERENCES: STARK RESIDENCE FOUNDATION REPAIRS USGS: 7.5' SERIES TOPOGRAPHIC MAPS, ESRI/I-CUBED/NATIONAL NOTE: BLACK AND WHITE GEOGRAPHIC SOCIETY2013 REPRODUCTION OF THIS COLOR EDMONDS, WASHINGTON ORIGINAL MAY REDUCE ITS SNOHOMISH CO: STREETS, CITY LIMITS, PARCELS, 3/21 EFFECTIVENESS AND LEAD TO PROJ NO. DATE: FIGURE: LOCATIONS AND DISTANCES SHOWN ARE APPROXIMATE INCORRECT INTERPRETATION 20210191EO01 9/21 1 / y r ;iL o 1. :x • . 6F r{. •w _ .I - f 1� lr F � � �1� I P ,t A. Coun unty L Co n o n f sT - LEGEND a s s❑ C I a t e d SITE PARCEL N earth SCIer1Ces O EXPLORATION CONTOUR 10 FT n I n C❑ r p❑ r a t e d BORING ,/ \V CONTOUR 2 FT 60 EXISTING SITE AND DATA SOURCES / REFERENCES: Feet EXPLORATION PLAN WA STATE LIDAR PORTAL: NORTH PUGET SOUND 2016 ACQUIRED MARCH - SEPT 2016,GRID CELL SIZE IS3' STARK RESIDENCE FOUNDATION REPAIRS CONTOURS FROM LIDAR NOTE: BLACK AND WHITE SNOHOMISH CO: STREETS, PARCELS 3/21 REPRODUCTION OF THIS COLOR EDMONDS, WASHINGTON KING C0: EAGLEVIEW TECHNOLOGIES, INC., AERIAL 2019 ORIGINAL MAY REDUCE ITS LOCATIONS AND DISTANCES SHOWN ARE APPROXIMATE INCORRECTINEFFECTIVENEINTERPAND RETATION PROJ NO. DATE: FIGURE: INCORRECT INTERPRETATION 20210191 E001 9/21 2 APPENDIX Exploration Log U EZ °o Well -graded gravel and Terms Describing Relative Density and Consistency o p o o OW g ravel with sand, little to 2) Density SPT blows/foot w o no fines Very Loose 0 to 4 Coarse-4 to 10 o o o 0 o 0 0 o o o GP Poorly -graded gravel 0)Loose > U) c> o o - v, o �,o w Grained Soils Medium Dense 10 to 30 Test Symbols 0 0 o 0 0 0 o and gravel with sand, Dense 3o to 50 little to no fines Very Dense >50 G = Grain Size M = Moisture Content ° 0° 0 Silty gravel and silty 6 Z C LO o Consistency SPT(2�blows/foot Y A= Atterberg Limits c a S GM gravel with sand Very Soft 0 to 2 C = Chemical Fine - v ~ ` .Soft ° 0 ° 0 2 to 4 DID =Dry Density Grained Soils c E 0 .i Medium Stiff 4 to 8 K = Permeability g o Stiff 8 to 15 Clayey gravel and Very Stiff 15 to 30 N NI Gc clayey gravel with sand Hard >30 o L Component Definitions o Well -graded sand and t Descriptive Term Size Range and Sieve Number m SW sand with gravel, little Boulders Larger than 12" o Li u e to no fines Cobbles 3" to 12" m ;n a� _ eveeeveeee Gravel 3" to No. 4 (4.75 mm) Poorly -graded sand con c i °' A SP and sand with gravel, Coarse Gravel 3" to 3/4" Fine Gravel 3/4to No. 4 75 mm " 4 (� ) 4) c cn o v N o little to no fines Sand No. 4 (4.75 mm) to No. 200 (0.075 mm) 0 z Coarse Sand No. 4 (4.75 mm) to No. 10 (2.00 mm) 6 o y � SM Silty Sand and Medium Sand No. 10 (2.00 mm) to No. 40 (0.425 mm) silty sand with Fine Sand No. 40 (0.425 mm) to No. 200 (0.075 mm) N v c N o a tp.-::'::. gravel Silt and Clay Smaller than No. 200 (0.075 mm) (3) Estimated Percentage Moisture Content Na sc Clayey sand and co NI clayey sand with gravel Component Percentage by Weight Dry - Absence of moisture, Trace <5 dusty, dry to the touch Slightly Moist - Perceptible Silt, sandy silt, gravelly silt, moisture o ML silt with sand or gravel Some 5 to <12 Moist - Damp but no visible u7 c T w Modifier 12 to <30 water Clay Of low to medium o `—° (silty, sandy, gravelly) Very Moist - Water visible but d CL plasticity; silty, sandy, or not free draining z •= gravelly clay, lean clay Very modifier 30 to <50 Wet -Visible free water, usual) Y NE (silty, sandy, gravelly) from below water table 0- a == Organic clay or silt of low Symbols 2 — OL plasticity Blows/6" or 0 Sampler portion of 6" Cement grout o Type / i surface seal Elastic silt, clayey silt, silt 2.0" OD Sampler Type o o �, MH with micaceous or Split Spoon p Description (4) Bentonite seal � o or fine sand or Sampler p 3.0" OD Split -Spoon Sampler - :-= Filter pack with A o silt (SPT) 3.25" OD Split -Spoon Ring Sampler (4) . - ; . :: blank casing :: Clay of high plasticity, v) U o c � CH sandy or gravelly Clay, fat _ Bulk sample 3.0" OD Thin Wall Tube Sampler section Screened casing m E J clay with sand or ravel Y g (including Shelby tube) _ or Hydrotip =with filter pack U — c Grab Sample - End cap c ;% Organic clay or silt of o Portion not recovered OH medium to high (1) (4) Percentage by dry weight Depth of ground water plasticity (2) (SPT) Standard Penetration Test 1 ATD = At time of drilling ASTM D-1586 (3) ( ) Q Static water level (date) In General Accordance with w Peat, muck and other rn _ c a, 0 PT highly organic soils Standard Practice for Description (5) Combined USCS symbols used for and Identification of Soils (ASTM D-2488) fines between 5% and 12% Classifications of soils in this report are based on visual field and/or laboratory observations, which include density/consistency, moisture condition, grain size, and g plasticity estimates and should not be construed to imply field or laboratory testing unless presented herein. Visual -manual and/or laboratory classification 3 methods of ASTM D-2487 and D-2488 were used as an identification guide for the Unified Soil Classification System. T O! ° a s s o c i a t e d earth sciences EXPLORATION LOG KEY FIGURE Al N o i n c o r p o r a t e d a assaClaIeC Exploration Borin e art h s c i e n cc s Project Number Exploration Number Sheet incorporalec 20210191EO01 EB-1 1of1 Project Name Stark Residence Foundation Repairs Ground Surface Elevation (ft) 19 Location Edmonds, WA Datum NAVD 88 Driller/Equipment Geologic Drill Partners / Mini -Bobcat HSA Date Start/Finish nc)/19/911C)9/1 /91 Hammer Weight/Drop 140# / 30" Hole Diameter (in) F cC Ch .2 O c .O a) n � > J CO U) 3 Blows/Foot w d) a S E `2 �, O u) o m m p� T K DESCRIPTION " ° 10 20 30 40 ` Topsoil - 8 inches Fill Slow gravelly drilling 0 to 3 feet. 5 Moist, light brown, fine SAND, some silt, trace debris at top; massive 2 S-1 (SP-SM). A4 2 t Recent Beach / Marsh Deposits 10 Wet, gray, fine SAND, some silt; layer of peat (4 inches thick) at tip of 11 S-2 sampler; organic odor; massive (SP-SM). A3 2 15 Moist, light brown to grayish brown, SILT, some fine sand; frequently 3 S-3 bedded with fine organics; thinly bedded with peat; interbeds (1 to 2 inches thick) near top and bottom of sampler (ML). 4 20 S 4 27 " Whidbey Formation Gravelly drilling at 20 feet; drill action increases; speed slows. 0/ " 50/ Very moist, gray, fine to medium SAND, trace silt, trace organics; massive (SP). Pre -Whidbey Glacial Till Drill action increases; speed slows. 25 S5 Moist, gray, silty, fine SAND, trace gravel; unsorted diamict (SM). 0/„ 50/ " Adding water due to difficult removal of sample at 20 feet. Driller notes interbedded, gravely, sandy drilling. Very slow drill progress 27 to 30 feet. 30 S_g Moist with wet coating from above and added water, gray, silty, fine SAND, 0/ 50/ " ace gravel; unsorted diamict (SM). Bottom of exploration boring at 30.4 feet Groundwater encountered 8 to 15 feet. Sampler Type (ST): m 2" OD Split Spoon Sampler (SPT) ❑ No Recovery M - Moisture Logged by: JG m 3" OD Split Spoon Sampler (D & M) Ring Sample Q Water Level Q Approved by: JHS ® Grab Sample 0 Shelby Tube Sample 1 Water Level at time of drilling (ATD)