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HomeMy WebLinkAboutSWP272167 1 ' GEOTECHNICAL ENGINEERING STUDY Highlands Community Church Addition 3031 N E 10th Street Renton, Washington Project No. T-2160 1 1 ........................................................... .... .... . :.::.: :.::.::.::.::.::::.::::::.::::;.:;:.:: :::.:::.:::.:::.::.::::::.:::.::.::.;:.::.::.::.::........::.:. .:.::> Terra Associates, Inc. . . . :: ' Prepared for: Highlands Community Church Renton, Washington 1 cm OF RENTON �E G E ! V ED FEB 2 5 1593 October 2, 1992 ' I&ILDING DIVISION 1 _ ... _ _.. .. _ _. ..._...._ ....... ..........._.._.. _ _ _ ... _. .... ......_.._ ......._. � • �"' 4' TERRA ASSOCIATES, Inc. ' ►A ♦ li Consultants in Geotechnical Engineering, Geology • and ' Environmental Earth Sciences ' October 2, 1992 Project No. T-2160 Mr. David Peterson ' c/o Highlands Community Church 3031 NE 10th Street Renton, Washington 98027 ' Subject: Geotechnical Engineering Study Highlands Community Church Addition 3031 N.E. loth Street Renton, Washington tDear Mr. Peterson: We have completed the geotechnical study you requested for the proposed addition to the Highlands ' Community Church in Renton, Washington. The location is shown on the attached Vicinity Map, Figure 1. The purpose of our study was to explore the subsurface soil and groundwater conditions in order to provide ' recommendations for site preparation, foundation design, and earthwork construction procedures. The scope of our work included test pits, laboratory tests on representative soil samples and geotechnical engineering analyses. This report presents the findings of our study and summarizes our conclusions and recommendations. In general, all or part of the site is underlain by fill containing extensive debris. The fill overlies the original ' topsoil layer which together extend to a depth of eight to nine feet. Underlying the original topsoil layer, the soils consist of medium dense, fine to medium grained, silty sand. We understand that much of the addition site was once a residential street with underground utilities. It is our opinion that the proposed ' addition may be constructed using conventional spread footings placed on competent native soils, where it can be reached, or on structural fill. The existing fill should not be used to support the proposed structure. ' Alternatively, the addition may be supported on augered concrete piles which extend below the fill and topsoil layers and into the competent native soils. However, additional exploration would be necessary to develop design criteria for piles. ' 12525 Willows Road, Suite 101, Kirkland, Washington 98034 9 Phone (206) 821-7777 Mr. David Peterson ' October 2, 1992 This report describes our explorations and explains our recommendations in greater detail. We trust this ' information is sufficient for your present needs. Please call if you have any questions or need additional information. ' Sincerely yours, TERRA ASSOC TES, INC. ' Dennis B. Green Project Engineer Theodore J. Schepper, P.E. Principal Engineer I•x°'gEs 6118/93 ' DBG/TJS:tm cc: Mr. David Peterson, GBP Architects Mr. Dave Young, 19131 SE May Valley Rd, Issaquah, Washington 1 Project No. T-2160 Page No. ii TABLE OF CONTENTS Page ' 1.0 Project Description 1 2.0 Scope of Work 1 ' 3.0 Site Conditions 2 3.1 Surface 2 3.2 Subsurface 2 3.3 Groundwater 2 4.0 Discussion and Recommendations 2 ' 4.1 General 2 4.2 Site Preparation and Grading 3 ' 4.3 Foundations 4 4.4 Ground Floors 4 ' 4.5 Lower Level Retaining Walls 4 4.6 Lateral Load Resistance 5 ' 4.7 Drainage 5 4.8 Slopes and Embankments 5 4.9 Excavations 5 f4.10 Utilities 6 5.0 Additional Services 6 ' 6.0 Limitations 6 Fi ores Vicinity Map Figure 1 Exploration Location Plan Figure 2 Soil Classification System Figure 3 Test Pit Logs Figure 4 Grain Size Analysis Figure 5 ' Appendices ' Summary of Relevant Design Parameters Appendix A Field Exploration and Laboratory Testing Appendix B ' (i) Geotechnical Engineering Study Highlands Community Church Addition 3031 N.E. 10th Street ' Renton, Washington ' 1.0 PROJECT DESCRIPTION The project consists of a proposed addition to the Highlands Community Church located at 3031 ' NE loth Street in Renton, Washington. The project location is shown on Figure 1. Based on the site plan provided to us, we understand that the addition will be to the west side of the existing gymnasium building. The addition will consist of a two story building having twelve classrooms, two ' stairwells and foyers, and an elevator. The ground floor will match the gymnasium ground floor. However, at the north end of the gym building, where the locker rooms are located, the existing floor and foundation steps up approximately five feet while the proposed addition adjacent to this ' area will remain at the lower elevation. ' Based on our experience with similar projects,we anticipate that the structure will be supported by a system of bearing walls and isolated interior columns. Structural loads are expected to be about 3 to 5 kips per foot for bearing walls and about 30 kips for interior columns. Once plans have been finalized, we should be provided an opportunity to review foundation and earthwork drawings and specifications. At that time we can provide supplementary ' recommendations, if needed. ' 2.0 SCOPE OF WORK Our scope of work was outlined in detail on our proposal to you dated August 13,.1992. Our ' proposal was accepted and we were authorized to proceed on August 31, 1992. Accordingly, our field exploration consisted of excavating two test pits at the site. Based on information obtained both in the field and laboratory, analysis was performed to develop recommendations for design and construction. Specifically this report addresses: 1. Site preparation and grading 2. Foundation support alternatives ' 3. Floor slab support 4. Design lateral earth pressures ' 5. Subsurface drainage Project No.T-2160 ' October 2, 1992 3.0 SITE CONDITIONS 3.1 Surface ' The southern two-thirds of the site of the proposed addition is relatively flat. Presently it is a gravelled surface and is used as a parking area and access road to nearby paved parking areas. In ' the northern portion of the addition site the ground surface slopes moderately upward approximately fifteen feet to a paved parking and delivery area. The slope is landscaped with shrubs and trees. A terraced path constructed of soil and railroad ties leads from the gravelled iparking area up the slope to the delivery area. We were told by several members of the church that the addition site lies in an area that once was a ' residential street. The entire area, including the property on which the church is built, was at one time occupied by government housing. 3.2 Subsurface The upper soils at both test pit locations consist of loose to medium dense fill. In the test pit located near the middle of the proposed addition, the upper five feet contains extensive debris including metal, cut-off pile butts, asphalt, and large concrete elements. The fill encountered in the southern test pit consists of a much cleaner silty gravelly sand containing some asphalt. Underlying the fill in both test pits is about two feet of native, loose,reddish brown sand with silt. This soil unit ' is underlain by medium dense,silty sand to a maximum explored depth of 12.5 feet. 3.3 Groundwater No groundwater seepage was encountered in either of the test pits. The test pits were left open for only a short time. It should be noted that groundwater levels can vary seasonally with rainfall and other factors. 4.0 DISCUSSION AND RECOMMENDATIONS 4.1 General ' Our study indicates that all or part of the site is underlain by five to six feet or more of uncontrolled, non-homogeneous fill containing extensive debris. The native soils underlying the fill consists of loose to medium dense silty sands. The uncontrolled fill should not be used to support building or floor loads. The medium dense, native sandy soils are competent and will provide adequate foundation support for the planned construction. ' Page No.2 Project No.T-2160 ' October 2, 1992 Based on our study, it is our opinion that the proposed addition is feasible, although site ' preparation may be more costly and time consuming than anticipated. The building addition may be constructed using conventional spread footing foundations placed on competent native soils or ' on structural fill. However, neither footings nor floor slabs should be placed on the uncontrolled fill. Alternatively, the structure may be supported on augered concrete piles extending through the fill and into the competent native soils. However, obstacles to drilling may be encountered which require removal before drilling can continue. If excavation at the north end of the project site is to proceed below the bottom of the existing footings, underpinning may be necessary. Underpinning may also be necessary elsewhere if excavations adjacent to existing footings are required to extend below existing footings in order to remove unsuitable soils. Underpinning should be completed before the excavation proceeds below ' the footings. Elsewhere,shoring may be necessary if cuts can not be adequately sloped. ' Our recommendations should be incorporated into design and construction of the project. The following sections of this report present more detailed recommendations pertaining to the geotechnical aspects of site development. 4.2 Site Preparation and Grading Uncontrolled fill should be removed from the building footprint, and the desired grade restored with structural fill. Where removal of the fill requires an excavation below an imaginary plane ' extending laterally a footing width from the base of the existing footing and then downward an angle of 1:1 (H:V), underpinning may be necessary. Alternatively, footing trenches may be excavated to competent native soils and filled with lean mix concrete. Trenches which will parallel the existing footing and extend below the aforementioned imaginary plane should be excavated and immediately backfilled with lean mix concrete in approximately ten foot sections. Each section ' should be completed prior to excavating the next. Excavation to remove remaining existing fills below the building could them be accomplished inside the lean mix once it has cured. ' We recommend that any soils to be imported for use as structural fill be evaluated by Terra Associates, Inc. before they are brought onto the site. For import fills, we suggest that no more than five percent of the soil fraction passing the 3/4-inch screen be finer than the No.200 sieve, and ' that the fill has a maximum aggregate site of six inches. All structural fill,other than lean mix concrete,should be placed in horizontal layers and compacted to a density equal to or greater than 95 percent of its maximum dry density, as determined by ASTM Test Designation D-698 (Standard Proctor). The fill material should be placed at or near the optimum moisture content. The individual fill layers should not exceed twelve inches in loose thickness. Structural fill beneath footings should extend beyond the footing a distance equal to the fill thickness. ' Page No.3 Project No.T-2160 ' October 2, 1992 4.3 Foundations The planned building addition may be supported on conventional spread footing foundations bearing on the competent native soils, or on the lean mix concrete or structural fill placed over ' competent soils. Footings may be proportioned for maximum bearing stresses of 2500 pounds per square foot, considering both dead and live loads. When wind or seismic loads are included, a one- third increase is permissible. Continuous wall footings should be at least 12 inches wide and isolated column footings at least 18 inches square. Footings exposed to the weather should bear at least 18 inches below adjacent outside final grades. ' Alternatively, augered concrete piles may be used to transfer structural and floor loads to the underlying competent soils. Additional subsurface exploration would be necessary in order to ' determine design criteria. However, we anticipate that 12 inch diameter augercast piles fifteen to twenty-five feet in length would provide load bearing capacities of 20 to 25 tons each. However, considering the debris encountered at Test Pit TP-1, excavation to remove obstructions to pile advancement should be expected. 4.4 Ground Floors Ground floors may be structurally supported or constructed as slab-on-grade. Slab-on-grade floors ' may be supported on competent native soils or on structural fill placed on competent, native soils. The existing fill should not be relied upon to support slab-on-grade floors. To provide a capillary ' break, we recommend placing at least four inches of free-draining fill, such as pea gravel, beneath the slabs. In areas where moisture is undesirable, a plastic barrier at least ten mils thick should be placed on the gravel. An inch or two of sand may be used to protect the membrane during ' construction and aid in curing concrete floor slabs. 4.5 Lower Level Retaining Walls Basement and retaining walls should be designed to resist lateral earth pressures imposed by the ' soils they retain. Walls free to rotate about their base may be designed to resist an equivalent fluid weighing 35 pounds per cubic foot (pcf). Walls restrained at the top should be designed to resist an additional uniform pressure of 100 pounds per square foot (psf). The above pressures assume a maximum wall height of twelve feet and that no hydrostatic forces, adjacent high footings, surcharge loads, or sloping backfill will occur above the walls. If any of these are expected, we ' should be contacted for the appropriate design criteria. Retaining and foundation walls should be backfilled with compacted free-draining granular soils containing no organics. The backfill material should meet the criteria for soils imported for use as structural fill, as described in Section 4.2 of this report. In general, on-site native soils are useable as backfill however, the existing fill soils are not. ' Page No. 4 Project No.T-2160 October 2, 1992 The purpose for using a free-draining, granular backfill is to assure that the design pressures on the ' retaining walls are not exceeded due to hydrostatic pressure build-up behind walls. Perforated pipe drains should be installed at the base of the wall footings, and free-draining backfill should be ' placed behind the walls. These pipes should drain to the storm drain system. ' 4.6 Lateral Load Resistance Lateral loads on foundations due to backfill stresses, wind, or seismic loads may be resisted by passive soil stresses on the sides of footings and foundation walls, and by friction on the base of foundations. We recommend estimating passive resistances based on an equivalent fluid weight of 300 pounds per cubic foot (pcf). This value assumes that the footing concrete is poured against "neat" excavations or that the backfill is compacted to at least 95 percent of its ASTM D-698 (Standard Proctor) maximum dry density. The calculated friction resistance at the base of foundations should not exceed 40 percent of the foundation dead load. 1 4.7 Drainage We recommend the use of drains at the base of all foundation and retaining walls. The drains should empty into the storm drain system. The footing drains should be surrounded by at least six inches of pea gravel wrapped in geotextile filter fabric such as Mirafi 140N. Roof drains should be separately tightlined to the storm drains. In areas adjacent to the building, final site grades which are not paved should be sloped away from the buildings. 4.8 Slopes and Embankments Although we do not anticipate that fill slopes or embankments will be required on this site, we point out that all fill slopes should be constructed with a finish inclination of 2:1 (Horizontal:Vertical) or flatter. Any permanently exposed slopes should be immediately seeded with appropriate species of vegetation to reduce erosion potential. 4.9 Excavations ' Excavation slopes should be constructed in conformance with the limits specified in local, state, and national government safety regulations. Temporary cuts up to four feet high may be made vertical. For slopes higher than four feet, temporary cuts in the medium dense, native soils should have an inclination no steeper than 1.5:1 (Horizontal:Vertical). ' Page No.5 Project No.T-2160 ' October 2, 1992 4.10 Utilities ' Where utility lines are to be excavated and installed in the paved parking areas,we recommend that all bedding and backfill be placed in accordance with APWA and all applicable local and state specifications. Excavated on-site native soils will generally,be suitable for backfill of utility trenches. Backfill placement and compaction should be in accordance with the recommendations given earlier in this report. ' 5.0 ADDITIONAL SERVICES We recommend that Terra Associates, Inc. be provided the opportunity to review the final design ' and earthwork specifications in order to verify that our recommendations have been properly interpreted and implemented in the project design. To observe compliance with the design concepts,specifications and recommendations, and to allow expedient design changes in the event subsurface conditions differ from those anticipated, we also ' recommend that Terra Associates, Inc. be retained to provide geotechnical services during construction. These services should include: ' 1. observing installation of augered piles or piers if used; 2. observing all earthwork operations and the placement and compaction of any structural fill that may be required; 3. observing all footing and slab areas prior to forming and concrete placement; ' 4. performing field density tests on compacted fills and backfills; 6.0 LIMITATIONS The analyses and recommendations submitted herein are based on data from two test pits. However, actual subsurface conditions may differ from those observed in the test pits. The nature and extent of any such variations may not become evident until construction. ' If variations are observed during construction, Terra Associates, Inc. should be requested to evaluate the actual site conditions and review the recommendations in this report prior to proceeding with construction. ' This report has been prepared specifically for this project. It is the property of Terra Associates and is intended for the exclusive use of the Highlands Community Church and its representatives. We do not guarantee project performance in any respect, only that our work meets normal 1 standards of professional care. No other warranty,expressed or implied, is provided. ' Page No.6 21- VE — _ •.« _ - _ � q t zz?' . YEJ ST 1 si IfOr« 5 s -A S ' IAST; "�t�`' _ .E a•_ 3. _`«t 4 r iE RNI - t SE,+-5_ } 1..,Z 11T«s«> fr« Iz 'Sf 1011-ST TN IT.opE NE SE iss y I Trn S I— 7W oI S T wf I.T"S• f fT ,_ z N +E + STI■ n +B NE F IITN a 9 KT Sn'I < j'r i NI Nf Pq RK< 3 ; r•\ 1E IIIN z IL S TZ I p; NLNfR M �` 1•4 I T ;i� SE "5TN -T - �C!- \i\� 9TN_. 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'APw+oRRo�41-•.•!r � � .. 19 .�i t � 2 1 VICINITY MAP TERRA HIGHLANDS COMMUNITY CHURCH ASSOCIATES RENTON,WASHINGTON Geotechnical Consultants Proj. No. 2160 Date 9/92 Figure 1 I ' - LEGEND t f ® TP-1 APPROXIMATE TEST PIT LOCATION J dZ Cnz- i \ - ,0 r 04 KIRKLAND AVENUE NE 40 0 40 80 V=40' scale feet TERRA EXPLORATION LOCATION PLAN HIGHLANDS COMMUNITY CHURCH ASSOCIATES RENTON, WASHINGTON ' Geotechnical Consultants Proj. No. 2160 Date 9/92 Figure 2 MAJOR DIVISIONS LETTER GRAPH TYPICAL DESCRIPTION ' SYMBOL SYMBOL GRAVELS Clean GW : O .• Well-graded gravels, gravel-sand mixtures, little � Gravels ••Q•p• •. or no fines. J an 9 (less than • • • • • • Poorly-graded gravels, gravel-sand mixtures, little a; More than 5% fines) GP ; ; ; ; ; ; or no fines. 50% of coarse N fraction is GM ' ' Silty gravels, gravel-sand-silt mixtures, non- ' W a; > larger than No. Gravels • •: • •: • plastic fines. Z E•� 4 sieve. with fines . . Clayey gravels, gravel-sand-clay mixtures, plastic GC . . . . . . fines. N SANDS Clean SW Well-graded sands, gravelly sands, little or W O o Sands no fines. N co Z (less than More than ° Poorly-graded sands or gravelly sands, little Q •' 50% of coarse 5/° fines) SP or no fines. C fraction is V o smaller than SM ; Silty sands, sand-silt mixtures, non-plastic fines. No. 4 sieve. Gravels with fines $C Clayey sands, sand-clay mixtures, plastic fines. N N SILTS AND CLAYS ML Inorganic silts and very fine sands, rock flour, silty or ' J y clayey fine sands or clayey silts with slight plasticity. > Inorganic clays of low to medium plasticity, gravelly N (a� Liquid limit is less than 50% CL• clays, sandy clays, silty clays, lean clays. 0 Z o N QL i l l l l l l l Organic silts and organic clays of low plasticity. 1 � IIII W CZ SILTS AND CLAYS MH Inorganic silts, micaceous or diatomaceous fine sandy or silty soils, elastic. ' W v« Z Liquid limit is greater than 50% CH Inorganic clays of high plasticity, fat clays. co y I I Organic clays of medium to high plasticity, OH ' organic silts. HIGHLY ORGANIC SOILS PT Peat and other highly organic soils. DEFINITION OF TERMS AND SYMBOLS Standard Penetration 2" OUTSIDE DIAMETER SPLIT aDensity Resistance in Blows/Foot T SPOON SAMPLER ' Very loose 0 4 2.4" INSIDE DIAMETER RING SAMPLER Loose 4-10 OR SHELBY TUBE SAMPLER Medium dense 10-30 P SAMPLER PUSHED ' c Dense 30 50 * SAMPLE NOT RECOVERED Very dense >50 SZ WATER LEVEL (DATE) n WATER OBSERVATION STANDPIPE ' Standard Penetration C TORVANE READINGS, tsf g Density Resistance in Blows/Foot qu PENETROMETER READING, tsf v Very soft 0-2 W MOISTURE, percent of dry weight `o Soft 2-4 pcf DRY DENSITY, pounds per cubic foot J Medium stiff 4-8 LL LIQUID LIMIT, percent stiff 8-16 rn Very stiff 6-32 PI PLASTIC INDEX ' Hard >32 N STANDARD PENETRATION, blows per foot SOIL CLASSIFICATION SYSTEM ' TERRA HIGHLAND COMMUNITY CHURCH ASSOCIATES RENTON, WASHINGTON Geotechnical Consultants Proj. No. T-2160 Date 9/92 Figure 3 Logged by: DBG Test Pit No. TP-1 Date: 9-14-92 Depth (ft.) USCS/ Soil Description W 0— Graph M Brown-black silty gravelly SAND dry, loose (Fill) Ism Concrete, asphalt metal debris, pile ends. silty,5— Brown SAND, moist, loose (Fill) 18 12 SPSM Red-brown SAND with silt, fine to medium grained, moist, loose. 10 qm Brown silty SAND, fine to medium grained, moist, 14 medium dense Test pit completed at 12.5 feet. No groundwater seepage encountered Some caving in upper 5 feet. Test Pit No. TP-2 Logged by: DBG Date: 9-14-92 Depth (ft.) USCS/ Soil Description W Graph 0 Brown, silty gravelly SAND, fine to medium grained, moist, 6 Sm medium dense. Asphalt at 2 to 3 feet. (Fill) 5 'T 9 A 14 sp S Red-brown SAND with silt, fine to medium grained, moist, sm loose. Brown, silty SAND, fine to medium grained, moist, medium 10— Ism I dense. 6 UT Test pit completed at 11 feet. I I No groundwater seepage encountered. No caving. TEST PIT LOGS TERM HIGHLAND COMMUNITY CHURCH ASSOCIATES RENTON, WASHINGTON Geotechnical Consultants Proj. No. T-2160 � Date 9/92 � Figure 4 SIEVE ANALYSIS �wwwlw�w■wwlwl■�wlwwiw►����ww�w�ww■ww�w■��w■��■■■■wl�wwww� .� ww�w == MwwMmmm�mmmmbl-*�'ww/ww■www■w■w�ww��■■■■��wwww� • wwl,��wl�wwlwl■�wlw����►�w>,�w���w■�����■■■■���� ww�����w��■��w�����ww.�w�w�ww�w■���ww��■■■■��w�ww� �������■�wlw�wl��`��ww/ww■w�w■��www'�■■■■��wwww� • ww�ww�www■wwlwl■��w����►�\ww■w��w■m �B■/■■mm� • � • • ww�ww�w�w�wwlwl■��w����ww�\��w��w■wl�w�ww��■■■■wl�w�� • ww�����w��■��w����ww���ww■ww�w■��■�www■■■■■■���ww� ww�wwwlww���■��wwl����►����m■m�ww�■■■■■���ww� . � ww�ww�w■w■wwlwl■��w��w���ww����ww■ww�w■��ww��■■■■��wwww� .• mom • wwwlww�www■wwlwl■��wwl���ww�■�\ww■ww�w■��w�ww�■■■■■���� w�ww�ww�w�wl■��w�����■�\w��w■��w■ww�■■■■■��www� ww���ww��wl■��wwlwl��������■�wlww��■■■■���� wwwlww�www■wwlwl■��wwl���ww�wls.�ww�w■wl�wwww�■■■■■��ww� • ����wlwwlwl■��w�w1���wl�il��w■��wwww��■■�■��wwww� � ww�ww�w�w■w�wl■��w����ww��ww�wo•w■wl�wwww�■■■■■��w�ww� • • w���www■��■��w�����w•■w►�ww�w■�w1w11��■■■■�wlw�ww� •■ �����wwlwl■��w�wl���w��ww►��w■�wlw��■■■■■�wlw�� • • ww�������■�wl������iww1�w■��wwwww■■■■■■��wwww� .� �_ww���wwiwl■��w�����wwllw�r�w■wl�www��■■■■��w�ww� �ww�www■wwlwl■�wlw����ww�w�•�ww\�w■wl�wwww�■■■■■��w�ww� •• • ���ww�wwlwl■��w�w1���w�\�wwwc 7■wl�wwww�■■■■■��w�ww� � • �������■���������\mow■����■■■■■���� • �ww�www■w� ■C�w�wl��_�w�wwlwww■�■���_�_■■■■■�_��_�_ • � �wwwllw■wN • 2101 • 1 1silty SAND • • SAND with silt APPENDIX A ' SUMMARY OF RELEVANT DESIGN PARAMETERS ' Soil Bearing Capacity2500 sf P ' Wall Pressures Unrestrained 35 pcf EFP Restrained 35 pcf EFP to plus 100 psf uniform Passive 300 pcf EFP Friction Coefficient 0.40 APPENDIX B FIELD EXPLORATION AND LABORATORY TESTING The field exploration was conducted by an engineering geologist from our firm who classified the ' soil conditions encountered, maintained a log of each test pit, obtained representative soil samples and observed pertinent site features. All soil samples were visually classified in accordance with the Unified Soil Classification system described on Figure 3. On September 14, 1992,we performed the field exploration with a rubber-tired backhoe owned and operated by Evans Bros. Backhoe Service of Bellevue, Washington. Subsurface soil conditions at ' the site were explored by excavating two test pits to a maximum depth of 12.5 feet below existing grade. The approximate test pit locations are shown on the Exploration Location Plan, Figure 2. ' Logs of the test pits are presented on Figure 4. Representative soil samples obtained from the test holes were placed in closed containers and taken to our laboratory for further examination and testing. The moisture content of each sample was measured and is reported on the test pit logs. Grain size analyses were performed on two samples;the results are shown on Figure 5. 1 t 1 1 1 1 1 1 1 1 1 1 1 1 Short Plat (SHPL # ) REQUEST FOR PROJECT 9 Prclim. Plat (PP# ) CAGH To: Technical Services Date 07 '?V WOa Green# 9&S7 7 -- From: Plan Review/Project Manager K KtTT121c ­ Project Name \WLJ AfJSt , C'ON&MO►.�lrt/ dNuyzcG+ Abbrnc>0 (70 characters max) Description of Project: W AME12- SaA-)OR-, S7 b 12.E I Vk 10 pOU04C->JT-S W/b(2AW_ t NSTALUkgIt3K) Circle Size of Waterline: 08- 10" 12" Circle One: or Extension Circle Size of Sewerline: 8" 101, 12" Circle One: fe� or Extension Circle Size of Stormline: 62" 15" 18" 24" Circle One: Ne or Extension Address or Street Name(s) �D3 (�,�, , I © I Dvlpr/Contractor/Owner/Cnslt: C4kJPC X+ (70 characters max) Check each discipline involved in Project Ltr Drwg it of sheets per discipline L9""'Trans-Storm N, (Roadway/Dminage) (Offsite improvementsxinclude basin name) (include TESC sheets) ❑ Transportation (Signalization.Channelizatim Lighting) Cl[,-Wastewater IJ , t-t�C1la l t.�D S ✓ 1� `� (Sanitary Sewer Main)(include basin name) L� Water (Mains,Valves,Hydrants) L (include composite&Horizontal Ctrl Sheets) TS Use Only I F—E - 4 0 - 1 -7 13 — ,1-► 67 OJT cz�? — )_�('—� SOP - I� - ai 67 Approved by TSM - Date rorrns/misc/92-090.130C/CD.Ibh