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HomeMy WebLinkAbout1993.05.21 - Geotechnical Design Report for Blue Heron School- -, ".. " ^..',......, e*;'*q* i-,4i&,:d, r_" (\ Mgers Biodgnamicsi inc. -rnv[onnental engineets & Port Townsend School District No. 50 Heery International 450 Fir Street Lincoln Building Port Townsend, Washington 98368 Myers Biodynamics, Inc. 600 Winslow Way East Suite 235 Bainbridge Island, Washington 98110 May 21, 1993 Project No. 93386-5 GEOTECHNICAL DESIGN.REPORT Port Townsend School Distoict PnoposedMiddle School Site (Site B) Prepared for: EXHIBIT Prepared By: ( Middle School93386-6 May 21, 19b3 ( TABLE OF COI{IShITS INTBODUCTTON .............. INFORMATION REVIEW... r......,; PROJECT DESCRIPTION...... SITE DESCRIPTION. ....:......... .......;................:... GEOLOGICALLY SENSITTVE ANEA,S. . . . Liquefaction MAPPING REVIEW. GENERALIZED SUBSURFACE CONDITIONS.... ......J 1 1 2 2 3 3 3 4 Fill .. Tonsoil Orrf.urqch Laeustrine Groundwater INFILTRATION TEST RESULTS GEO"ECHNICAL ENGINEERING BECOMMENDATIONS..... ...........8 Site Preopration and Grading Sf.rrrcf.rrrql F ill Site Soil Suitahilitv as Struchrral FillCut nnd Fill Slones. ..........., Foundation Sunnort Slah-On-Grsde Floors Drainage Considerations .. Subgrad e .Wall s. Lateral Resistanee Pavement Considerntions ........ General Erosion Control Considerations RECOMMENDATIONS FOR ADDITIONAL SERVICES.. CLOSURE APPENDD( A - FIELD EXPLORATION PROGRAM APPENDIX B - LABORATORY TESTING APPENDIX C . INFILTRATION TESTING 4 5 5 5 6 6 8 10 11n 12a ut L4 L4 14 15 15 16 Myers Biodynamics, Inc.3 . ......... 4"-bii.6in!i-5itu!rni;/, CMiddle School93386-5 May 21, 1993 page 1 of 16 INTRODUCTION This report presents the results of the geotechnical investigations and design recommendations for the Port Townsend School District Proposed Middle School Site (Site B). The site is located offofSan Juan Avenue in Port Townsend, Washington. The purpose of our work was to obtain'subsurface information, perform field and laboratory testing, arid develop a geotechnical engineering design report for the project site. Our understanding of the project was based on infbrmation provided to us and through discussionswith the P-ort Townsend School District project coordinator. The geotechnical scope oi wor.k for thisproject was conducted'in general accordance with our proposal dated March 24, tggg and theAgreement For Consultant Services dated April 1,' 1993. The scope of work included, review ofreadily available information, site reconnaissance,' subsurface explorations and infiltrationtesting sample collection and laboratory testing, geotechnical analyses, and preparation of thisreport. Results of the exploration program, laboratory, and infiltration testing are presented inAppendicesdBandC. .T INFORMATION REVIEW Readily available information was collected and reviewed for evaluation of the project site.Information review included the following items: . o Port Townsend Environmentally Sensitive Areas Ordinance, Number 2319. . Soil Survey of Jeffersori County Area, Washington (U.S. Department of Agriculture Soil Conservation Service, 19?S). ' Port Townsend North Quadrangle, Washington-Jefferson Co., 7.5 minute Series(Topographic), U.S. Geological Survey, 19b3, photo revised 1981. ' Unconsolidated Deposits of Port Townsend 30 by 60 Minute Quadrangle, Puget Sound Region, Washington (U.S. Geological Survey Map I-1198-D, 1986).. ' Bedrock Geologic Map of Port Townsend 30 by 60 Minute Quadrangle, Puget Sound,Washington, (U.S. Geological Survey Map, I-1199-G, lggg). ' Site Survey For Port Townsend School District No. 50, Proposed Middle School Site B, Clark Land Oftice, May 6, 1gg3. (Topography) , Topographic Aerial Survey of 19?5, City of Port Townsend, Jefferson County, Washington, Northeast V4, Section 3 and South east 7J4 Section 34, Township 30 North, Range 1 West. . Test Hole Logs (conducted by others), Ap;il 18, 1986. Aerial photography provided by project coordinator (date unknown).a Myers Biodynamics, Inc. . ..,.i: 4 .- -., ^.-.,-.,....A"..\,.a&'triiriildr;{a;are. Middle School93386-5 May 21, 1993 page 2 of 16 PROJECT DESCRIPTION The project site is approximately 34 acres in size and is located west of San Juan Avenue in Port Townsend, Washington. The project Viciirity Map is presented on Figure 1. The site is boundecl on the east by San Juan Avenue and on the northeast by a cemetery. The north, south, and west side of the site is bordered by private property consisting of residential and pastute land. A wetland area is located in the west central portion of the site as indicated on the Site and Exploration PIan, Figure 2. The propo5ed project development consists of the construction of a new middle school facility rvhich includes a single story structure, an access road off of San Juan Avenue, parking areas,. recreational fields, and stormwater control facilities. At the time of our work, the location and'extent of proposed facilities was not determined. However, a prelimlnary project site plan provided to our office indicates the south end of the site will be utilized for athletic fields. The east- . central portion of the site will be the location of the proposed structure. The access drive andparking areas will be located along the east side of the site adjacent to San Juan Avenue. The north end of the site may be utilized for athletic fields and parking, although probably not as a part of this project. We understand that no development is proposed within the existing site wetland. A preliminary grading plan provided to us indicates the general proposed grades for the project development features. The proposed structure will likely be constructed with a finished floor elevation of approxim ahely 24 feet. Site grades for proposed athletic fields within the south end of the site will be approximately 24 to 28 feet. Column loads for the structure are not known at the time of our report. However, we understand that the proposed structure will be single story and that loads will be relatively light. SITE DESCRIPTION The site consists of gently rolling topography with a relatively level wetland area located in the west-central portion ofthe site. The general site topography and wetland area are presented on the Site and Exploration Plan, Figure 2. IVlaximum site elevations ar.e about 35 feet in the northeast portion of the site and at the top of thd knoll in the east-central portion of the site. Broad, relatively level topography extends east io west across the center of the site as shown on Figure 2. The central and western portion of this broad area contains the wetland. At the time of our site observations in March and April 1993, standing surface water was present, within the wetlands. Topography within the wetland area and surrounding area is rblatively level with elevations ranging fiom 14 to 1? feet. Topography indicates no surface water outlet for the wetland. A closed topographic depression also exists at the southeast corner of the site with a low elevation of approximately 1? to 18 feet. The east-central area of the site directly $'est of San Juan Avenue and south of the cemetery has been recently filled. Historic topography (1975) indicates pre-fill ground surface elevations in the recent fill area of 20 to 22 feet which sloped gently west into the existing wetland. Maximum fill heights of about 4 feet have been placed within this area. Current ground surface elevations in the recent fill area are 24 to 25 feet. Existing stockpiles of recent, end-dumped fill and debris are located at the west end of the recent fill. Several large topographic knolls located in the north-central and northwest portion of the site reflect stockpiles of sod (see Figure 2). It is reported that this sod was stripped from the site and Myers Biodynamica, Inc. Middle School93386-5 May 21, 1993 page 3 of 16 stockpiled prior to the recent fill placement described above. Debris from a former residence on the site was also observed at the north end of the site at the time of our field investigations. GEOLOGICALLY SENSITryE AREAS The Port Townsend Environmentally Sensitive Areas Ordinance defines and outlines development requirements for geologically hazardous areas. Geologically hazardous areas include erosion hazard areas, sensitive slope and pdtential mass movement areas, steep slopes (> 407o), stream.or wave erosion areas, and seismic hazard areas. Based on the City of Port Townsend map of iieologic Hazards - Soismic (Draft, July 8, 1gg2), aportion of the project site is mapped as an area of high to extreme seismic hazard. The area shown on the mapping is'in the west-central and northwest portion of the site (wetland area). No development is planned.in the wetland area. However, recent site fill on the site could also be considered a seismic risk under the Ordinance due to the loose nature and potential for settlement induced by ground shaking during a seismic event. The proposed Middle School Structure will be located in the fill area. Due to other geotechnical considerations including foundation support and differenlial settlement concerns, design recommendations w.ill preclude the use of existing fill soils for support of thestructure. The Geotechnical Engineering Recommendations section of the report presents recommendations for support of the proposed structure on compacted structural fill or on firm native site soils. Liouefaction A sudden loss of soil strength can occur during an earthquake and lead to the loss of foundation support for a structure, large settlements, slope failures, soil flows, or large lateral soilmovements. Th. process leading.to this loss of soil strength is termed soil liquefaction. Liquefaction is primarily associated with relatively loose, saturated, cohesionless (granular) soi I s. The project site contains areas of relatively loose, cohesionless soils as described in the Generalized Subsurface Conditions section of the report. However, no groundwater or evidence of a groundwater. table within the granular soils *"r obr.*ed in the d.pth of the site explorations. Thus, the observed site conditions indicate liquefaction ivould not occur on the project site within the depth of the site explorations. In addition, the majority.of loose site soils will either be o<cavated as a part of site grading or will be overexcavated and replaced by compacted soils within the area of the proposed middle school structure. MAPPING REVIEW U.S. Geological Srirvey geologic mapping reviewed for the project shows glacial soil deposits in the project site area. Mapping indicates primarily glacial till soils (very dense mixture of gravel, sand, silt, and clay) but other deposits of granular soils or fine grained soils are possible. The northeast corner of the site is mapped as coarse grained, granular soils (sand and gravel). Site explorations inilicate glacial till is not generally located within the depth of the explorations. However, granular soils are.located within the northeast corner of the site as indicated on geologicmapping. t Myers Biodynamics, Inc. -.*, -.r,,6;{Bi:.d...;.riaL68t*r' C Middle School93386-5 May 21, 1993 .page 4 of 16 Soil Conservation Service (SCS) soils mapping indicates two soil types within the site: Agnerv Si,lt Loam and San Juan Gravelly Sandy Loam. The Agnew soil is mapped primarily within the siiewetland and was formed in valley areas formerly occupied by shallow glacial lakes (Lacustrine soil). The San Juan soil is mapped on the remainder of the site and was formed in areas of glacial drift and outwash plains (Outwash soil). Site explorations generally confirm these two soiftypes on the project site. However, the aerial extent of.the Lacustrine soil is much greater than that mapped by SCS. SCS indicates both soil types have slow runoff and slight erosion potentials. GENERALIZED SUBSURFACE CONDITIONS The project site was explored by conducting twenty six test pit explorations, TP-{ through TP-20. The approximate test pit locations are presented on the Site and'Exploration Plan, Figure 2. Discussion ofthe field procedures and test pit logs are presented in Appendix A Laboratory testprocedures and results for selected site soil samples are presented in Appendix B. Near-surface soil permeability conditions were also investigated by performing infiltration tests at fourlocations on the site. Infiltration test locations, IT-1 through IT-4, are shorvn on Figure 2. Appendix C'presents infiltration test hole logs and test procedures. Site explorations indicate variable soil conditions across the project site. In general, site.soils can be classified into four general soil units: Fill, Topsoil, Outwash (sand./sand with gravel), and Lacustrine (clay) soils. The Fill soil was recently placed on the site (reportedly within the last !ear). Topsoil formedwithin the surface of the native site soils. The Outwash and Lacustrine soils were deposited byglacial activity. The Lacustrine soils were deposited by calm glacial lakes and subsequently overridden and consolidated by the weight of glacial ice. Consequently, the clay soils have a verystiff to hard consistency prior to disturbance and when located below the surface zone ofrveathering. Glacial Outwash soils were deposited by melt water flowing arvay from the glacier. Outwash materials at the site are typically sand or sand with gravel. The General Site Soils Map, Figure 4, indicates the predominant geologic origin of the site soils'(Lacustrine or Outwash soil deposits) below the Fill and Topsoil units on the project site. Fill Fill soils are located within the east-central portion of the site directly west of San Juan Avenue.The recent Fill area could be visually identified at the time of our explorations by evidence of recent grading, bare ground, and./or sparse vegetation. Fill rvas encountered in test pits TP-1, TP- 2 (trace), TP-4, TP-5, TP-6, and TP-13 at the locations shown on Figure 2. Fill thicknesses ranged from 3 to 4 feet in test pits TP-1, TP-5, TP-6, and TP-13. Fill was L 1/,2 feet,thick in TP-4 and a trace amount of fill was observed in TP-2. Subsurface Profile A-A, Figure' 3, generally shows the extent of Fill across this area of.the site. Fill soils encountered in the majority of test pits (TP-l, TP-z, TP-4, TP-s, and TP-6) consisted of loose, silty sand with gravel soils, occasional rubble, and organics. We understand that a significant' quantity of construction rubble may have been placed within the Fill area although significant rubble was not encountered in the test pits. Some of the stockpiles of material present at the edge of the recent fill area were observed to contain construction rubble'(primarily concrete), vegetation, and other debris. The Fill observed in TP-13 (adjacent to San Juan Avenue) consiste{ Myers Biodynnrnics, Ihc. C Middle School93386-5 May 21, 1993 page 5 of 16 primarily of relatively soft, wet, clay soils with a strong sulfur odor. We understand that some site Fill soils may have come from the excavation for the wastewater treatment plant currently under construction at the North Beach area of Port Townsend. The wet, clay Fill soils encountered in TP-13 may have such'an origin. The Fill located in the vicinity of TP-13 was relatively soft and significant rutting of the soil occurred under the weight of the backhoe which caused difficulties in backhoe movement. ToDsoil Topsoil was observed in all test pits Advanced on the project site. In the recent fill area;Topsoil was present below the fill. Topsoil ranged from 1 to t U2 feet in thickness in most of the test pit explorations..several test pit explorations (TP-14, TP-l?, TP-18, TP-24, and TP-25) showed 4 6 I inches of Topsoil thickness. Topsoil generally consisted of dark brown to black, silty sand with gravel and organics. Outwaqh (sand/sand with gravel) Outwash'soils were generally observed in the north end of the site in the vicinity of test pits TP-14 through TP-17 and TP-19 (see Figure 4). Outwash soils were also generally present in test pits TP- 2, TP-3, TP-8, TP-20, and TP-21 advanced in the topographic knoll on the east side of the site adjacent to San Juan Avenue. Outwash soils at the north end of the site typically consisted of loose tci medium dense sand with gravel soils. Caving of the test pit walls within the upper 2 to 3 feei of the Outwash soils rvas common. Outwash soils in the knoll area consisted of loose to medium dense sand rvith gravel and fine to medium sand. Typically, the fine to medium sand underlay the sand with gravel soils. Caving was also common in the upper 3 to 6 feet of these Outwash soils. Within the coarse grained sand with gravel Outwash soils, chunks and lenses of hard clay rvere encountered. These clay soils were observed to occur randomly within the Outwash soils and the surface of the clay was highly irregular. At times within some of the test pits, the clay dominated the soil exposed on the test pits walls. Lacustrine (clad Lacustrine soils apfear to cover the majority of the project site. They dominate the southern portion of the site (TP-22 through TP-26) and undirlay the wetland area (test hole logs by others), the northwest corner of the site (TP-18), and the broad central and recent fill areas (TP-1, TP-4 through TP-?, TP-9 through TP-13). A 2 foot layer of weathered clay was also present below the topsoil layer in test pit TP-8. Generally, the Lacustrine soils observed in the test pits consisted of very stiff to hard, massive, clay. Near the top of the Lacustrine clay soil, a weathered zone was observed that consisted of a more friable soil with roots, silt, sand, and occasional gravel. This weathered zone was not observed at' the top of the irregular clay chunks and lenses occurring within the sand with gravel Outwash soils. Mycrs Biodynamics, Inc. .,....r,:-- Middle School93386-5 May 21, 1993 page 6 of 16 Groundwater No groundwater was observed in the test pit explorations advanced on the site except ui, on. location. A trace amount of seepage was noted in test pit TP-23 where a pocket of sand with gravel,, on top of the clay, contained a small amount of perched groundwater. Mottling was noted during the explorations on top of the Lacustrine clay. This indicates perched groundwater is likely present above the clay during periods of heavy precipitation. This perched groundwater tends to flow laterally following the general trend of existing site topography. The wetland area appears to be formed by perched water dbove hard Lacustrine clay soils. Direct incident rainfall, surface water flows, and perched groundwater from the Labustrine soil areas surrounding the wetland appear to provide the hydrologic input to support the wetland. Test pit explorations performed adjacent to the wetland (and explorations by others within the wetland) extended below the level of wetland (and associated surface water) and did not encounter rvet, soil conditions even within pockets or zones of clean granular soils. Consequently, there appears to be no significant site groundwater component (other than localized perched groundwater) that supports the site wetland. , Figure 4 presents the general elevation at which relatively impervious Lacustrine clay soils rvere encountered in the site explorations. Elevation of the top of the clay indicates that within the majority of the site, near-surface perched groundwater tends to flow in a direction that reflects the general site surface topography (typically into the wetland). In the southeast quadrant of the site, perched groundwater moves to the closed depression at'this corner of the site. The Outwash soil areas shown generally on Figure 4 rapidly infiltrate vertically but it is uncertain as to [he overall direction these waters move. No continuous clay or other impervious layer was encountered below the Outwash soils within the depth of the test pit explorations. However, it is possible that such layers are present below the exploration depths ofthe test pits. INFILTRATION TEST RESULTS Four locations on the project site were identified by the project coordinator as potential locations for stormwater infrltration systems. The specifrc design approaches were ilot selected at the time of this report. Infiltration tests (IT-1 through IT-a) were conducted at the locations as shown on Figure 2. Infiltration test procedures and logs of the soil encountered during excavation of the test holes are presented in Appendix C. Descriptions presented on the infiltration soil logs. and are based on the USDA soil textural classification system in accordance with the EPA "Design Manual for Treatment and Disposal Systems". The USDA soil classification differs from the engineering soils classification system used for the test pit exploration program. USDA soil textural descriptions are presented in the following discussion in brackets. Soils encountered in the infiltration test holes were consistent with soils observed in the test pit exdavations. Logs of infiltration test holes are presented in Table Cl of Appendix C. Infiltration test locations IT-1, IT-3, and IT-4. were located within Lacustrine soil areas of the site as shown on Figure 4. Topsoil [gravelly loam to gravelly sandy loam], overlying variable soil horizons [gravelly sandy loam to silt loam to clay loam], over clay lclay] was generally observed at these locations. IT-2 was located at the edge of an Outwash area of the site (see Figure 4). The IT-2 test hole extended through Topsoil 0oamy sandl, a weathered granular soil horizon iloamy sandl and a thin clay zone fclay loam to clay], and into the fine to medium sand [sand]. The IT-2 sand soils Myere Biodynamics, Inc. ( Middle School93386-5 May 21, 1993 page 7 of 16 are similar to those fine to medium sand soils encountered a! various depths in TP-2, TP-3, TP-8, TP-20, and liP-21. Infiltration test results are presented in Table l below. IT-1, IT-3, and IT-4 infiltration test resultshighlight the extreine variability of infiltration rates within the Lacustrine. areas of the site.Infrltration rates ranged from 13 minutes per inch to virtually impervious conditions (no measurable infiltration during the testing interval). IT-2 represents Che rapid infiltration rate of the Outwash sand. TABI.E 1 Pnoposed Middle Scfrcol Site Soil Infilbstion TestingApril 1998 a Per EPA "Design Manual for Treatment and Disposal Systems"b USDA textural classification as recommended under EPA methodologry.* Water level holding at26 inches below grade after 20 hour soak. No measurable water level drop below 26 inch depth during infiltration test readings. The IT-1 test interval measured infrltration within the dense, cemented sand under the hard, Lacustrine clay at that location. Cementation, the dense condition of the sand, and the hard, relatively impervious clay resulted in no measurable infiltration rate within the soil profile during the tesL Infilbation Test No. Gmund Surface Elevation Geet) Test Intenral in inchesbelqw existingg:ade (apprcximate elevation in feet) Penblatior: nste (Miautes- pertrndr )a Soil T!rye Within Testinglntenalb IT.1 L9 tlz',{.{.Clay (hard), massive, over Sand, (dense), cemented TT.2 20'25" -46" (18'- 16) <2 Clay Loam to Clay (stiff1, over Sand (loose) IT.3 L9 Uz',25" - 36" (L7 y2' - L6 U2') 100 Gravelly Sandy Loam over Clay Loam (34 - 36"), wet @ 30 - 34" TT.4 22',24" - 35" (20'- 19) T}Gravelly Sandy Loam over Clay Loam Myere Biodynamica, Ina. Middle School93386-5 May 21, 1993 page 8 of 1.6 IT-3 test results indicate 100 miMnch infiltration rate. 'The test interval was located withinweathered soil horizons furavelly sandy loam and clay loaml. The slow infiltration rate waslikbly due to the presence of wetted condition of the clay loam within the soil profile. The IT-Blocation is adjacent to a topographic depression. It is likely that perched groundwater above therelatively im_permeable Lacrrstrine clay is present in this area particularly during wet weatherconditions which would reduce infiltration ratcs. It is 'unknown whethei a culvJrt drains thistopographic depression to the other side of San Juan Avenue or if water is retained within thisdepression The IT-a-test location'results indicate a relatively rapid infrltration rate which is faJter thanwgul{ be anticipated for a soil horizon in the Lacustrine clay soil area. At this locationi however, arelatively free draining soil horizon lgravelly sandy loam] was present above the weatherldLacustrine clay [clay loam]. this gravelly sandy loim zone reflects the measu""a pui.oiulionrate of 13 minutes per inch. In this area of the site, topography slopes down.to the wltland andprovides a gradient for shallow perched groundwater to move laieraliy away (downslope) from thepoint of introduction. Results of the infiltration test IT-2 in the fine to medium sand indicate an infiltration rate of lessthan 2 minutes per inch. This rate is likely representative of the fine to medium sand soilsobserved in the test pit explorations in the southern knoll Outwash area shown on Figure 4. Itshould be noted that it is unknown what limiting soil or groundwater conditions are present belowthe depth of the test pits in this area that could influence infiltration capacity of these loils. Also, inOutwash areas where infiltration rates are very rapid, the nature of the nat-ive soils may need tobeconsidered if the soils are expected to provide water quality treatment to site stormwatlrs. Designmeasures may need to be incorporated to protect groundwater quality. GEOTECHNICAL ENGINEERING RECOMMENDATIONS deohchnical engineering recommendations presented in the following sections are based on theresults of the site reconnaissance and subsurface explorations, laboratory test results, and ourunderstanding of the proposed site development at the time this report was piepared. Site Prenaration and Grading Site preparation should consist of the removal of vegetation and strippingof the Fill and Topsoil inthe areas of proposed structures, roads, parking lots, and athletic netas. The Topsoil can bestockpiled for reuse in landscaping or other restored areas. Stockpiled soil should te protectedfrom erosion. A portion of the excavated Fill may be suitable for reuse as structural fili but willlikely require selective grading and stockpiling. Not all of the existing'Fill soils are suitable for reuse as structural fill. Based on the results of our subsurface explorations, the Fill and Topsoil range in thickness from 1U2 Lo 5 feet within the proposed building location. Outside of the general building location andexisting Fill area, Topsoil thicknesses range from a inches to 1 V2 feet. The eiisting Fill isvariable in nature and ranges from silty sand with gravel or clay soils, to rubble, to velehtivedebris. The Topsoil is typically a brown to dark brown, silty sand with gravel containing organicmaterial. Reference the Generalized Subsurface ConditionJ section of the report and th! teJt pitlogs (Appendix A) for detailed descriptions of observed soil conditions. . Myels Biodynamics, Inc. C Middle School93386-5 May 21, 1993 page 9 of 16 After stripping of the Fill and Topsoil we recommend that the subgrade soils in areas scheduled to receive structurgl fill or pavement sections be proofrolled with a fully loaded, l0-yard dump truck or similar healy equipment. Soft or loosened soil areas should be reconditioned and compacted,or removed and replaced with structural fill. Recommendations for structural fill placement followin a subsequent section of this repbrt. Table 2 summarizes the Fill and Tbpsoil thicknesses observed at the tist pit locations. The combined thickness of Fill and Tbpsoil reflects the recommended stripping depths below the existing site ground surface. TABLE 2 nxisting Fill and Topsoil Tbiclsesses Proposed lvfiddte School Site 6iteB) Test Pit Fill Topsoil Combined TP.1 TP.2 TP-3 TP.4 TP.5 TP.6 TP-7 TP-8 TP.9 TP-10 TP.11 TP.12 TP-13 TP-14 TP.15 TP.16 TP-1? TP.18 TP.19 TP.2O TP.21 TP.22 TP.23 TP.24 TP.25 TP.26 3 feet 3 inches L ll2feet 3 feet 4 feet 3 Lf2feet, 1 foot Lll4ferlt U2fooL LU2fee-;b 1 foot 1 foot LU2ferlt 8 inches 10 inches LLl'2fwb IWfeet LU2feel 1 foot 9 inches LU2feet 1 foot U2foot U2foot 1 foot 1 foot 1 foot ! U?foot r fobt 4 inches 4 inches t ll}feeb 4 feet L U2feet U2fooL 3 feet 4feet 5 feet L U2feeb 8 inches 10 inches L U2feet L U?feet L U?feet 4 Lf2feet 9 inches L U2feet 1 foot tJZ foot U2.foot 1 foot 1 foot 1 foot L U2foot 1 foot 4 inches 4 irrches I U2feeL Lacustrine clay soils are sensitive to moisture and disturbance by construction equipment. These soils rapidly degrade when subjected to construction traffrc or when otherwise disturbed under wet conditions. We recommend site preparation and grading be abcomplished during dry weather. A working mat consisting of at least 6 inches of crushed rock should be utilized if exposed ilay soils become.softened or disturbed by traftic or wet conditions. As previously mentioned, much of the site is underlain by relatively impermeable, hard, Lacustrine clhy soils. During wet weather periods surface water will perch or pond above the clay. We recommend that stripped surfaces and cuts within the clay soils be sloped to drain at all times Myers Biodynamice, Inc. r..!4rir&l Middle School93386-5 May 21,'1993 page 10 of 16 during construction and that they be sloped to drain in the direction of existing site topographyprior to fill placemenL Keying of fill into the native site Lacuitrine soils should occur whill maintaining a slope for drainage If incliment weather is anticipited the surface of all exposed clay or other moisture sensitive soils shouJd be sloped to drain and sealed with a smooth roller to reduce the potentia!.for softening of the soils from rainfall and ponded stormwater. Site soils softened and/or disturbed by wet ,u.a-th"" o" construction activity should be scarified, dried, bnd compacted or removed and replaced withstructural fill. Sttucturaf Fill We recommend that fill placed a{acent to or under the proposed middle school structure, beneathpavement, or behind any subgrade walls be placed as structural fill. Structural fill .should consist,of'a well graded, granular soil free of organics, debris, or other deleterious material. Structural frll should be at a moisture content to allow for proper compaction. If construction and fill placement are to occur during wet weather conditions, we recommend that structural fill material meet the gradation requirements for "Gravel Borrow" as presented in Section 9-03.14 of the Washington State Department of Transportation Standard gpecifrcations for Road, Bridge, and Municipal Construction (Standard Specifications). However, the gradation should be modifred so that a maximum 5 percent by weight of the material passes the U.S. No. 200 sieve as based on the minus 3/4 inch fraction. Native sand with gravel site soils would generally meet the specification for Gravel Borrow based on soil grain size analysis (Appendix B). It should be noted that specific project features such as embankment fill for potential stormwater facilities may require soils with a sufticient fines content in order to detain or retain water. Project construction schedules should account for the dry weather conditions that would be required to place moisture sensitive materials in these specific project areas. Structural fill should be placed in lifts not exceeding 10-inches in loose thickness. Each lift shoulcl be compacted to the minimum relative densities presented below in Table 3. ' . TABLE 3 Recommended Shrctural Fill Compaction Fill Locption Minimum Relative Compaction* Beneath Floor Slabs or Footings Under Pavement Upper 2 feet Greater than 2 feet depth Exterior Subgrade Wall Backfill and Around Footings Embankment Fill for Stormwater Facilities Utility Trenches 95 percent 95 percent 92 percent 92 percent 95 percent same as adjacent locations or 90 percent minimum * Expressed as a percentage of the maximum dry density as determined by ASTM 155?. Mycrs Biodynamics, Inc. ( Middle School93386-5 May 21, 1993 page 11 of16 Site Soil Suitability as Structural Fill The suitability of excavated site soils for use as structural frll depends on the gradation andmoisture content of the soil when it is placed. As fte amount of fines (soil particles pasging theU.S. No. 200 sieve) increases, the soil becomes more sensitive to small changes in moiJture content and compaction levels become more diffrcult to achieve. Soils containing greater than dpercent fines or fine sands are moisture sensitive and cannot be consistently crimpacted to a firm, non-yielding condition when the water content is greater than the optimum moisture content. Theoptimum moisture content is that moisture content which results in the greatest soil compacted dry density for a given compaction effort The site soils generally consist of Fill (Silty Sand with Gravel or Clay); Topsoil (Silty Sand withGravel and Organics); Outwash (Sand with Gravel or Fine to Medium Sand); and Lacustrine(Clay). Results of laboratory testing included in Appendix B (Figures B-1 through B-a) indicate awide range .of fines content within the site soils. Fill. Silty sand with gravel Fill soils contain fines contents on the order of B0 percent. These Fill soils are very moisture sensitive and should be utilized as structural fill onlyduring extended periods of dry weather when the moisture content can be controllecl. Tirese soils should be protected from wetting during wet weather. If the soils become wet they may require spreading and drying prior to.placement as structural fill. Clay Fill soils and other fine grained or organic Fill soils excavated are not suitable for use as structural fill. Topsoil. Topsoil is not recommended for use as structural fill due to the presence of organics within the soil unit. Outwash. Fine to medium sand Outwash soils contain fines content of 2 to 10 percent and a significant quantity of fine sand. These soils are also somewhat moisture sensitive and rvould generally require dry weather during placement as structural fill when the moisture content can be controlled. The relatively coarser sand with gravel Outwash soils are generally clean, rvell graded, and are suitable for use as structural fill. The sand with gravel Outwash soils typically contain less than 5 percent fines and relatively small amounts of fine sand. Thus, they are suitable for use as structural fill during wet weather conditions. Lacustrine. Lacustrine (clay) soils are not suitatle for use as structural fill due to the fine grained, plastic condition, and extreme moisture sensitive nature of the soil. If wet rveather construction is anticipated or is required to meet the project construction schedule,we recommend structural fill be restrict6d to the native sand with gravel Outwash soils or imported soils consisting of a well graded sand and gravel with less than 5 percent fines as recommended in the Structural Fill section of this report. The fine to medium sand Oot*ash soils may be usable during intermittent wet weather conditions although it should be recognized that these soils are somewhat moisture sensitive (due to significant fine sand and fines) and may be difficult to place'and achieve required compaction levelJduring extended periods of wet weathlr. Miers Biodynamics, Inc. .'', -r,,.;'.v,^..1./- }.',trY@l' Middle School 93386-5 May 21, 1993 page 12 of16 Cut and Fill Slones Permanent cut slopes within the native site soils should be constructed at 3H:1V (3 horizontal to 1 vertical) rvithin the Lacustrine clay soils. Steeper slopes are possible within the hard clay Lacustrine soils under shor0 term conditions. Similar cut slopes are recommended in the loose granular sand./sand with gravel Outwash soils. Revegetation and erosign control of these Outwash soils will be greatly facilitated by 3H:1V slopes. Steeper slopes are possible within the Outwash soils but will be subjected to erosion, severe rilling, and gulleying if significant erosion control and revegetation measures are not employed. Fill slopes should be constructed no steeper than 2H:JV. Where clean sand or sand with gravel Outwash soils are utilized for lll slopes significant erosion protection would be required at 2H:lV or flattgr slopes (3H:lV) should be constructed. Slopes no steeper than 3H:1V are recommended for embankmlnt fill for construction of stormwater facilities. All embankment fill for stormwater facility cbnstruction should be keyed into firm native soils. Embankment fill should consist of silty sand with gravel soils or other well graded soils free from deleterious material and with. a sufficient fines content to detain or retain stormwater. Foundation SuoDort The proposed middli school structure finished floorelevation is 24 feeL. The locabion of the structure is in the east central part of the site (TP-3 through TP-g, TP-11, and TP-20). The majority of the building footprint lies within the area of existing Fill. The existing Fill material is unsuitable for foundation support due to its variable nature, potential rubble component, uncontrolled placement, and loose or soft consistency. The building area will require over excavation of the recent Fill and Topsoil and placement with siructural fill. Maximum structuralfill thickness of 5 to 7 feet will be required. A cut on the order of 6 feet will be required in the southeast portion ofthe proposed structure in the vicinity ofTP-S. Loose Outwash soils may be present in the cut at the proposed subgrade elevation in the southeast corner of the proposed structure. We recommend that loose soils be overexcavated until firm (medium dense or denser), granular Outwash soils are encountered. If medium dense conditions are not encountered, the excavation should extend to a depth equal to or greater than 2 times the least footing dimension. The excavation should extend outward from the base of the footing on a slope of at least 1/2H:IV. Overexcavated areas should be replaced with structural fill as previously recommended. If firm (stiff to hard) Lacustrine clay soils are exposed at subgrade elevations, we recommend the clay be removed to a depth of 2 feet below the subgrade elevation and replaced with structural fill: If wet or soft clay soils are encountered, they should be overexcavated until firm soils are reached. All footing foundation or slab-on-grade areas should be observed by a qualified geotechnical engineer grior to construction of the foundation elements to observe subgrade conditions for adequate support and allowable soil bearing pressures. The proposed middle school structure can be supported on shallow spread footings founded on structural fill or firm (medium dense or denser), native Outwash soils. We recommend that shallorv'spread footing foundations be designed for a maximum allorvable soil bearing pressure of 3,000 pounds per square foot (psfl for foundations on properly placed and compacted structural fill or firm, native Outwash soils. If subgrade soils becomes disturbed, loosened, or soflened prior to construction of the foundations, the soil should be overexcavated, reconditioned, and compacbed to 95 percent of the maximum dry density as recommended in the structural fill'section of this report. Myers Biodynamics, Inc. CMiddle School93386-5 May 21, 1993 page 13 of16 Minimum footing widths of 24 inches for isolated spread footings and 18 inches for continuous(strip)'footings are recommended. Allowable soil bearing presJotes may be increased by one-third to include short-term conditions such as seismic or wind loading. Footings should be embedded at least 18 inches below a{iacent finished exterior grades or the interior floor slab grade,. whichever is lower. We anticipate that individual footings designed for the maximum allowable soil bearingpressures recommended above will experience total settlement of one inch or less. Differentiai settlement between individual footings should not exceed V2 inch. The majority of settlement is expected to occur during construction although a.small percentage of the settlement (V4 inch or Iess) may occur over time. Slah-On-Grade Floors Slab-on-grade floors should be supported on properly placed and compacted structural fill or firm,native Outwash soils. Subgrade preparation in the floor slab area should conform to the recommendations presented in the Site Preparation and Grading and Structural Fill sections of this repqrt. We recommend placing at least 6 inches of clean, free draining granular material beneath the slab on grade floors to act as a capillary break. A suitable gradation for capillary break material would be Standard Specification 9-03.L2(2) Gravel Backfill For Walls. The clean sand with gravel Outwash soils would be suitable for use as capillary break material. Fine to medium sand Outwash soils should not be utilized. Drainage Considerations Site structures require adequate drainage to prevent the development of hydrostatic forces behind subgrade walls and to adequately convey water away from walls, footings, and slab-on-grade. We recommend that exterior site grades be sloped away from structures to prevent water from collecting adjacent to the structures and from percolating into soils next to subgrade walls. Roof downspouts should not be permitted to discharge into foundation drains. Stormwater should also not be discharged into foundation bearing soils a{acent to structures. Collected stormwater should be directed away from and downslope of the proposed structures utilizing the site stormwater system. Subsurface drainage should be provided for the building and behind any subgr-ade wall. A perimeter footing drain system should be placed at the base of the exterior edge of footings. Drains should consist of slotted, heary-duty, smooth'walled PVC pipe with a minimum diameter of four inches. Drain pipe should be completely surrounded by at least 6 inches of drain gravel. Draingravel should meet the gradation requirements given in the Standard Specifications Section 9- 03.12(4) Gravel Backfill For Drains. Filter fabric should surround'the drain gravel with a ininimum l2-inch overlap of the filter fabric edges. Convenient cleanouts should be provided to increase the useful life of the drains. Subgrade walls should be backfilled with clean free-draining sand and gravel placed within 18 inches of the wall. A suitable wall backfill material is presented in the Standard Specification Section 9-03.12(2) Gravel Backfill for Walls. Alternatively, a synthetic geocomposite drainage material could be utilized behind subgrade ,walls. Waii drainage *ate"ial ihould co,',nect hydraulically to the drain gravel surrounding the footing drain pipe. Myers Biodynarnics, Inc. Middle School93386-5 May 21, 1993 page 14 of16 Recreational fields sbould be designed with at least 12 inches of free draining granular soils overnative clay soils. All surfaces and in particular the recreation fields should be sloped to drain andrunoff collected in a perimeter stormwater system. Additional drainage within the recreational areas could also be achieved by spacing subdrains below the recreational fields. The subdrainsshould be surrounded by a filter fabric to protect against piping of finersoil particles into thedrainage system. SuMrains should be sloped to drain into the perimeter drainage system and berouted to the site stormwater system. Suherade Walls S-ubgradd walls which are-free to yield at least 0.001 times the height of the wall during bickfilling("active conditions") mgr be designed based on an equivalent fluid density of 3? poonls per cubiifoot (pc0. Walls whlch are structurally restrained. against yielding duiing backfilting ("at-rest conditions") should be designed for an equivalent fluid density of E? pcf. T!*" wall design values assume a horizontal backfill and no buildup of hydrostatic forces behindthe wall. The Drainage Considerations section of this repotl shoutd be referenced forrecommended drainage behind subgrade walls to'prevent the build-up of hydrostatic forces. Walls should be backfilled in accordance with the recommendations presented in the StructuralFill section of.the report. We recommend that only light weight, hand bperated compactionequipment be allowed to operate within 2 to B feet of subgrade walrs. Lateral Resistance Lateral loads may be resisted by friction along the base of foundations and by passive soilresistan-ce against buried foundations and subgrade walls. Footings on structurai ntt or nativeOutwash soils may be designed using a coeffrcient of base friction of O.a. This value includes afactor of safety of 1-5. Passive soil resistance may be calculated based on an equivalent fluiddensity of 200 pcf. This value includes a factor of safety of 2 in order to limit laterai deformations.Passive resistance values also assume a horizontal ground surface beyond the footing or wall.We recommend ignoring passive resistance for the upper 12 inches of soil unless covired by afloor slab or pavement. Pa.vement Consideration s Pavement subgrade should be prepared in accordance with the recommendations presented in theSite Preparation and Grading section of this report. We recommend that all pavement subgrade beproofrolled in the presence of a qualified geotechnical engineer to determine the presencJof firm,non-yie_lding subgrade soil conditions. Soft, wet, or loose subgrade areas observed duringproofrolling should be reconditioned and compacted to a firm, nsn-yielding condition br remouel and- replaced with structural frll. We recommend that proofrollinibe acc-omplished with 'a fullyloaded, l0-yard dump truck or other similarly loaded construction equipment. For design of pavement, we recommend that a California Bearing Ration (cBR) value of 20 be used for firm, non-yielding, silty sand with gravel, sand, or sand with gravel structural fill orfirm (medium dense or denser), native soils at least 12 inches in thickness. A CBR value of S is recommended for site Lacustrine clay soils. The following general pavement sections recommended for the school facility assume loadingfrom delivery trucks, buses, and potential fire truck traffic. A pavement section consisting of 5 Myors Biodynamice, Inc. ( Middle School93386-5 May 21, 1993 page 15 of16 Measure$must be employed to protect site soils from erosion and sediment transport into tlie sitedrainages and sensitive areas. According to SCS, site soils have a slight erosion poterrtial. However, exposed Outwash soils, particularly the fine to medium sand wil-l be subject to rilling,gulleying, and sediment tranSport when exposed on cut or fill slopes, Erosion contiol on cut anldfill slopes is important to reduce this tendency for Outwash soils to rill and gulley. These soilsshould be protected from erosion and revegetated as soon as possible. Erosion pioteciion on expose4soils should include as a minimum mulching and seeding and on steeper, cut and fill siopes Greater .than 3H:lV) the additional use of a fully biodegradable erosion control product such asjute matting is recommended on top of a several inch thick mulch. The jute matting shoulcl besecurely anchored by pinning or staking to the slope so as to achieve firm contact betrveen themulch material and the ground surface. It is anticipated that traditional techniques such as the use of biofiltration, siltation ponds, siltationfencing, and hay bales could be used to control site drainage, sediment transpor[, and siltationduring and after construction. Revegetation of all distufbed areas should also occur as soon aspossible. Stormwater discharge must also be controlled into the site wetland such that the stormrvatervolume, inflow rate, and water quality are not significantly modified from predevelopmenl siteconditions. Regular maintenance and inspection of erosion control and sedimenl facilities should be performed during construction and for permanent stormwater facilities. RECOMMENDATTONS FOR ADDITIONAL SERVICES We recommend additional infiltration testing be performed'on the project site. Inhltration testresults indicate a tremendous range of infiltration rates in the sitl soils. These raLes aredependent not only on aerial location of potential infiitration systems but also on the elevation or d:p_th below the existing ground surface at which the syltems aie propor.d. Due to the large extentof Lacustrine (clay) soils and uncertain extent of Outwash soits at the project site, variousmeasures for controlling stormwater should be considered. Once excavation- or proposed sitegrades penetrate into Lacustrine clay soils, conditions are essentially impervious to infiltration. In addition, we recommend that our firm be retainei to review those portions of the plans andspecifications that pertain to foundation and earthwork to determine whether they are consistentrvith the recommendations presented in this report. We also recommend that construction monitoring, testing, and consultation be. performecl toconfirm that conditions encountered are consistent with those indicated by our explorations, toprovide recommendations should conditions be revealed during construciion that differ from those anticipated, and to evaluate whether earthwork activities comply with contract plans and inches of asphalt concrete pavement over 4 inches base or crushed surfacing is recommended overstructural fill or properly prepared, firm, native Outwash soils at least 12 inches in thickness. Theasphalt thickness could be reduced to 2 to 2 V2 inches thickness where only light automotive trafficloading is anticipated.' For pavement over firm (stiff to hard), Lacustririe clay soils, 4 inches ofasphalt cpncrete pavement over 4 inches of base or crushed surfacing is recommended over 12inches ofsrllbase material. Subbase material should conform tb the general recommendations forstructural fill material and be compacted to 95 percent of the maximum dry density (ASTM.15S?). General Erosion Control Considerations Myers Biodynamics, Inc. ..:*--..4..d',ttl.,- Middle School93386-5 May 21, 1993 page 16 of 16 specifications. Such activities should include subgrade preparations for foundations, f'toor slabs,and pavement, proofrolling, structural fill placement and compaction, foundation soil bearingcapacity, and other geotechnical related earthwork activities. CLOSURE This report was prepared for the exclusive use of the Port Townsend School District No. S0 and its c-onsultants for specific application to the proposed middle school project site. The data and reportshould be provided to prospective contractors for their information but the report, conclusions, Lndinterpretations should not be construed as a wananty of subsurface conditioni. Within the limitations of ,.op., schedule, budget this report was prepared in accordance withgenerally accepted geotechnical engineering practices in this areaat-the time the report wasprepared. No other warranty either express or implied is made. The conclusions andrecommendations are based on our understanding of the project as described in the report and on-site conditions as observed at the time of our explorations. If project plans including building location, finished gxades, or other project features change from those described in this report we should be contacted and retained to review the changed con-tlitions.Also, if there is a substantial lapse of time between submission of this report and the start ofconstruction, or ifconditions have changed due to natural causes or construction operations at thesite, or ifconditions appear different from those described in our report, we should be contacted andretained to review our report. The purpose of the revierv is to determine the applicability of theconclusions and recommendations considering the time lapse and/or changed conditions. We appreciate the opportunity to be of service to you on this project. Please contact our office at your convenience should you have any questions or require additional services. MYERS BIODYNAI\{ICS, INC. Neff Principal/Project Geotechnical Engineer attachments JNM/dIh ,1. 003:;:4.i AI/nL I.1:i N. Ir4 EXPIRES Myers Biodynamics, Inc. ( ) I sr Z6<sztortz5(r<t<J 50tH sI proieciSiid n ,f\ N ST 62 c:'.ir SalH sT ST Ccmgct + 55TH STLt 5IRO o2. 6 q 6 FFOoo5u 66aOroJr9 tz oz StlH 5rst ST {9IH oJo F'n L!s.cl GrovcCcm! tc(y o 27TH OJ AIH S F6 I.I7TH AVE- *JoU. C.lhC.m! 35rH S.T OtsUq: z olicl. ry sT. sst @z I 37TH c o I5)6 l.l d ijJ Fo t Rd { 9.7 I l5 ':6 o.2 !n. F CAN.NESI AVE ST .CEDAR TREMONT s F!,ouqJa 54 U z)U o L6 C MILO ST vst sI ST g:yg:so: q,' :C) CuI> o f o q CoMein r @ iL: sr e( e{ 9' o t ,{ ST sr s sI Jq l{ qo: SI, sI ,, q sI srs po .. J. : S.L .q qF O _<4- . sr $,;3 ;€jrii- ffi Pon Town$nd Goll Cour:c I .._ l{Ir-{- F Fq 2JRO F ST, ST z :)x ST 22N0 2 lsr F. ot6 20TH ST ST F0 -gt' ?, 91 io v, Ji 4't 4< Sl . .Y tglsli" o FqJ *:=o L ti i6 710 z:, FIGURE NO 93386-5r-"Mgers Biodgnamics inc. 600 Winslow Way Easr BUS: (206) Bainbridge lsland WA 98 I I O FAX: (206f 842-6073 842-3797 Vicinity Map New Middle School OATE A Legend: ITP-I Approximate Test Pit Exptoration Location a lT-l Approximate tnliltratin Test LoationL-t Subsudaa Prolile Scale: l'= 200' Note.' Site Plan based on Clark Land Olliq, Site Survey lor port Townsend School Disda No. tu, Proposed Middte Schoot Site B, May 1993 0 200 Mgers Biodgnarnics inc.lq,600 Winslow Way East BUS: BainbdJge lsland WA 98t10 FAX: (206) 842-6073 (206) 842-37s7 Site and Exploration Plan New Middle School F|GUNE NO 2 PRO'ECI NO 93386.5 OATE Anrll'93 A30'WETUND10'LEGEND:TP4 Test Pit Exploration (see Figure 2lor location)Approrimate Zone of Proposed SttuctureTP.5ISan Juan AwnueEdge ol PavementTP.I3A'30'o*aleleetHorizonAl l'- 100'0 l0leet20'n'Fl!utlr=zo5g10. t'rFLrJUJt!z6k5uJTP.l20'0'ht:t{.lii:{H--FiilTopsoill-aarctrine (clay)- Ground surlace prolile (existing)- - -, Ground sudace profile (1975)EEt Verlica! l'= 10' INGURENO3JOB NO93386-soArE ifav'93Generalized Subsurface Profile A-A'New Middle Schoolr""MgersBiodgnamics inc.600 Wnslow Wav East BUS: (2061Bainbridge lsland WA 98110 FAX: (206iu2-6073842-3797 ( I TP.l8 TP.I9 WETUND t @,,t\ N @ ASH'lzwt/ .,:- r" .i ,'/,'m TP-|5' ,/'r.;i:4' TP.I6 I I TP.T7 .-( (\t TP.1 CEMETARY E TP.I @ tlJ5 =t! { e =o -t TP.26 TP.25 € RINd,TP.24 --.--J:'*.-.*..-.-..-J- "iL- Legend: lf!-l Approximare Tast pit Exploration Location) f-t Approximate tnfiltration Test Location@ Scale: t'= 200' E Fl:urt:lo-l top ol Lacustrine.(ctay) soil observed in the axplorationNote: Tp-B and tT-z exptoratiirrr'inii iii itir-tiii, ",etevalion shown over lree draining line to iedum sand Plinailf puwash (san&sand & gravel) t;ut top ot ctayobserued at etevation shown,"ni nunty iiiiJ"i' rlu]""",as chunks, or as lenses within the ouir",ri'riii--' ' o zoo @ Outwash.gand/sand E gravel) soi! - no clayobserued within the exploration to the crlrtom(elevation) ol the exploration shown lrrote: Site Plan based on Clail Land Oflice, Site Surveylor Port Townsend School Disrrict No. 50, proposed Middte Schoot Site B, May 1993 NO NO 93386-s Mgers Biodgnamics inc_r""600 Winslow Way EasrBainbridge lstand WA 98il0 (206) (206) BUS: FAX: 842-6073 842-3797 General Site Soils Map New Middle School (C APPENDD( A 1 Middle School93386-5 May 21, 1993 Appendix APPENDD( AFIELD DGLORATION PROGRAT{ Subsurface conditions for th-e project sitc were explored by excavating a total of 26 test pits atthe approximate locations shown on the Site and Exploration Plan, Figure 2.. Logs of tire testpits TP-lthrolgh TP-29 are presented on Figure A-1 through A-26. the tcst pitkplorations were conducted on Apil22 and April23, 1993. Test pits were advanced to depths rangingfrom 6 tn Lg V2 feeL The greater depths were performed in the proposed building and-anticipated cut areas. Subsurface conditions observed in the eiplorations ute pi".ented onthe logs attached to this appendix. The explorations were located in the field by taping or pacing relative to existing physicalfeatures. 1he approxim_ate ground surface elevation presented on the logs wereinterpolated from the Clark Land Office, Site Sunrey For Port Townsend'School DistrictNo. 50, Proposed Middle School Site B, May 1993. fire location and elevation of theexplorations should be considered accurate to the degree implied by the method used. The test pits were excavatcd with a backhoe under subcontract to our firm. Representativesoil samples were collected from the test pits, sealed in plastic bags or jars, ani transportedto the laboratory for analyses. The relative density of the soils, siownin parenthesis on thetest pit logs, was estimated in the field at the time of the explorations. A geotechnical engineer ftom Myers Biodynamics was present throughout the field work toobserve the explorations, obtain soil samples, and to prepare soil logs of the explorations.Soils were classified in general accordance with ASTM D-2488 "standard Practice forDescription and Identification of Soils (Visual-Manual Procedure)". The exploration logspresented in this appendix represent our interpretations of the contents of the field logs anlthe results oflaboratory testing. Infiltration testing was also performed at four locations on the project site. Test procedures and results of the infiltration testing are presented in Appendix C. Myere Biodynamics, Inc. (- TEST PIT LOG TP-l H,eWa',*:rff*v,*P;8,frtrWilXffi #W.Hlf ## Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDTTTONS: Recent flil, trace vegetatlon FILL: SILTY SAND WTH GRAVEL; brcwn, (loose), very moist to wet, trace rubble, organics, (straw, roots), trace clay SILT;ORGANIC browndark to traceblack,moist,tovery(soft), little sand and tine roots DESCRIPTION Pieces of anuete rubble at surface OLAY; light brown and gray, (stitf to very stitQ, moist to very moist, trace tine sand, massive becomes hard 5- 8- 11 - 14- 16- 17- 10 12 13 15 t8 I 2 4 6 7 9 U,uJ o. =U' 9.4 Flr Fo. uJo 9t 92 g3 Bottom ol test pit at B foot depth. completed and backtitted on 4/2293 abundant straw 2'to 3' depth Lab Test: MC = 14%, GS Lab Test: MC = 28% Lab Test: MC = 23%, Attb PP = 2.5 to 3 TSF TV>lTSF PP>4TSF Lab Test: MC = 27% COMMENTS 600 Winslow Way Bainbridge lsland FAX: (206) 8/,2-3797 EastwA 98110 DATE 412U93 ELEVAnOil (FT'25 FIGURE A-1 PRqIECT IIO 93386-5 lF ltfl-il=r.mics rnc.'7 MB BUs: (206) B4zsozg TEST PIT LOG TP.2 Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDTTTONS: Recenily graded, trace vegetailon ILt' o-ulo at,ul o.E U) TOPSOIL: SILTY SN,|D; dark brown to black, (toose), moist to very moist,trace to little gavel, fine roots, organics DESCR!PTION 0 to 3 inches FILL over sA,vD To slrLY s/d'tD wtrH GRAWEL; brown to tight gray, (toose tomedium dense), very moist, occasional cobbles 4, to e; ail'ieter CLAY; light brown and gray, (very stiff), moisl to very moist, massive pockets of clean sand and gravel, (medium dense to dense), moist SAND; gray brown, (medium dense), moist, fine to medium beames gray 4- 11 - r9- 15- 18- 2- 10 12 l4 16 3 5 I 7 6 ? I $s 96 91 92 94 $3 of test pit at 12 foot depth. compteted and backfitted on 4/22/93Bottom Lab Test: MC = t2o/i line roots Lab Test: MC = 9%, GS Lab Test: MC = 4V Lab Test: MC = |t% COMMENTS 600 Winslow Wav Bainbridge lstanci FAX: (206) 842-3797 East wA 98110 DATE 4t2U93 ELEVAIPN (FTI 28 FIGURE A-2 PRq'€CT I{C)93386-5 L Mgers IF Eiodgnamics inc.'f MB BUS: (206) 842€o7s I a TEST PIT LOG TP.3 H,F*W,y,E:!lW,;:y#,!e!?,?ffi tXWbWw,lf g,iw. I I 600 Winslow Way Bainbridge lsland FAX:(2ct6) 8423797 EastwA 98110 OATE 4122t93 EI-EVAnON (Fr) 30 FIGURE A-3 PRO'ECTNO 93386-5 Port Townsend New Middle School Site TEST PIT LOCATTON: See Ftgure 2 SURFACE CONDTTTONS: Sod, grasses FIl.riFo- UJo 6ul o- =a moist,SILTY SAND;daTK brown, DESCRIPTION SILTY sN'lD: red brown to tight gray brown, (loose to medium dense), verymoist, tra@ to little gravel grades to SAND; brown, (very loose to loose), moist, fine to medium grades to SAND WITH GRAVEL; brown, (toose to medium dense), moist CLAY; brown to gray, (hard), moist, trace organic partings, massive @ 7'depth wc4et of ctean sand and gpvet (tow end of rp) that connects toupper sand and gravel layer pockets and (enses of clean sand and gravel increasing, greater than 50% ofexpsed test pit sidewa.tts are sand anl gravel by l1'depth exposed test pit sidewails entirely sand and gravel SAND (mediumgray,medium toverydense),moist,tinetracecoarse, totracesand,finelitile occasional coarsegravel,gravel SAND; gray, (medium dense), very moist, fine to medium 5- 7- 9- 11 - 3- 15- 10 12 t4 16 17 18 2 3 4 6 8 91 92 93 $4 95 s..6 Bottom ol test pit at t3' 8" toot depth. completed and bacniiled on 4/22g3 8" diameter cobble, 2 l/2, diameter bulder LabTest: MC = B% caving from 2'to 4'depth LabTest: MC = 7% Lab Test: MC = 3l%, Attb PP > 4.5 TSF top of clay @ 4 1/2' depth, high end of test pit, slopes to 5 1/2' depth at mid point of test pit easy digging Lab Test: MC = 5% fine gravel slight caving COMMENTS tta illgers IF Biodgnarnics inc.'7 MB BUS: (206) 842€ozg (- TEST PIT LOG TP.4 a Port Townsend New Middle School Site SURFACE CONDITTONS: Recent fl[, trace vegetationTEST PIT LOCATION: See Ftgure 2 FTL Gr!o al,IU o- = CN FILL: SILTY SA /D WITH GRAVEL; brown, (toose), very moist DESCRIPTION TOPSOIL: SILTY SAND; dark brown to black, (loose), fftoist, abundant line roots, trace roots to l/2'diameter, abundant organics gray brown, (loose to medium dense), moist, trace to tiftle grades to SAND; brown, (medium dense), moist, tine to medium, tracegravel, trace coarse sand SN,|D; Iight gravel CLAY; brown to light gray brown, (very stiff to hard), very moist, trace organics and organic partings, massive, blocky fracture- at times becomes light gray brown, iron staining, trace fine sand at times 3- 8- 10- 13- 17- 11 12 14 16 18 2 4 5 I 15 6 7 91 92 93 s4 $5 Bottom of test pit at 12loot depth. compteted and backfiiled on 4/22/93 LabTest: MC = B% 3 bouldea greater than 2'diameter LabTest: MC = tB% 3'diameter boulder Lab Test: MC = 6% Lab Test: MC = 3l% 18" diameterboulder@ I 0', occasional cobbles and gravel, harder digging @ lt' COMMENTS PP = 2.5 75P TV> 1 TSF 600 Winslow Wav Bainbridge lslanci FAX: (206) 842-3797 East wA 98110 OATE 4t2?i93 ErMTloil(Fr)241t2 FIGURE A-4 PRqIECT NO 93386-s .tl^f Mgers !F Biodgnamics inc.' r MB 8US: (2C,6) 842€073 C TEST PIT LOG TP.s EH"W,fl.giffi,#,y#Ie,trffi ,#,yffi i#:frHl[## i { Port Townsend New Middle School Site area, trace vegetailonSURFACE CONDITIONS:Edge ol flllTEST PIT LOCATTON: See Ftgure 2 Flr o. u.to U' Ir,l o. =o FILL: SILIY SAND WITH GRAVEL; brown to light gray brown, (toqse), verymoist,occasbnalcobbles ' 't'- DESCRIPTION TOPSOIL:T;TYs/[TOSAA'D SANDY sn &rk brown to blad<,(locr,e), tracemoist,abundantgravel,fine rooEorganie, Ts/tSANDY tight bawn,Iitile(very moist,stift),tracecla14 andgravel SAND AND GRAVEL;brown, (medium dense), moist cLAY;.light brown, (very stiff to hard), moist to very moist, trace organics andorganic partings beames (very stitf to hard), moist, massive, trace oryanics stiff), very moist, trace organics and organicpartings beumes (stiff to very stift), very moist grades to CLAY; light brown, (very paftings, trace fine sand 6- 9- 2- 15- 1- 11 13 14 16 17 18 2 3 4 5 7 I 0 91 92 93 94 $5 96 97 at 13 1/2 foot depth. Compteted and bacfiitted on 4/2283Bottom of test pit LabTest: MC = 15y",69 Lab Test: MC = 15y" LabTest: MC = 2gy PP = 47gP Lab Test: MC = 3gy" PP = 3.5 to 4.5 TSFTV>ITSF PP = 4.9 to 4.5 TSF COMMENTS 600 Winslow Way East Bainbridge tslanci WA 9B1tO FA"\: (206) 8424m7 OATE 412U93 ELEVAnOX (FT) 23 FIGURE A-5 PRqJECTNO 93386-5f- H,},iHr.1;rcsinc' TEST P I T LOG TP-O ["x*,gr,#,srg,fr:y,;.pts,!,.#'ffi,i*w,rrrr',Er,trsiw E Fo-ulo oul o- =3n 91 92 s-3 Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Recent fifl, no vegetailon DESCRIPTION FILL: SILIY SAND WTH GRAVEL; brown, (loose), wet, octasionat cobbles COMMENTS LabTest: MC = 16% Sod / root layer@ 4'depth LabTest: MC = 24% tnce to little gravelupper 6" of clay PP> 4.5 Lab Test: MC = 25% TOPSOIL: SILIY SAND; dark brown to black, (oose), very moist, abundant organics, trace gravel CLAY; Iight brown, (very stiff to hard), very moist bemmes light gray brown, organic partings, massive, blocky fracture at times Bottom of test pit at 11 foot depth. Completed and backfilted on 4/22/93 600 Winslow Way Bainbridge lsland FAX: (206) 842-3797 EastwA 98110 OATE N2?/93 ELEYAnOil (Frl 23 FIGURE A-6 PRqIECT I{O 93386-5 l" lt:;l=,-mics inc.'7 MB BUS: (206)B42so7s TEST PIT LOG TP.7 a -r'#,i:#,a?ffi i#rr*w,trsi*- Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDTTTONS: Sod, grasses F1rt'Fo.]uo CNul o- =U, ToPSolL: slLw sN'tD To sANDy slLT dak brown to btack, (toose), very moist, abundant organics, fine roots, trace gravel, occasionat cobbles DESCRIPTION CLAY; light brown, (very strff), moistto very moist, tnce to titile sand, trace gravel, trace tine roots SNAIO WITH GRAVELT7 9AND AND GRAnEL; brown, (dense to very dense), very moist, wet jusl above clay layer 4'CLAY at 3 1/2' SILTTO CLAY; light brown, (very stiff to hard), moist grades to sandy silt, trace to litile gravel and occasional cobbtes grades to SILW SAND WITH GRAVEL (GLACTALTILL); gray, (very dense), stightty moist to moist, oeasional cobbles t- 4- 9- 2- 15- t0 11 13 14 18 2 3 5 6 7 8 6 7 9t $2 93 94 Bottom of test pit at I 1/2 foot depth. completed and backtitted on 4/22rg3 LabTest: MC = 15y" topsoll layer thinner @ pp slope side ot test pit LabTest: MC = 21% LabTest: MC = 5% trace cobbles and gravel 18" diameter boulder hard digging COMMENTS 600 Winslow Way East Bainbridge lslarri WA 98110 FAX: (206) e42-3797 DATE 4122t93 ELEYAIION(FT)21 112 FIGURE A-7 PRO'ECTTlo 93386-5 * lt-"#;-'amics inc.'7 MB BUS: (206) s42€073 e TEST PIT LOG TP'8 r'*sr,flt:e:w,*v#,!,.#ffit,x,ffiffiffi%1,r*i# Flt Fo.tIJo (tul o- =a Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Sod, grasses DESCRIPTION TOPSOIL: SITLY SA ID: daft brown to black, (loose), npist to very moist, Iittle gravel, abuMant organie, fine roots COMMENTS PP = 2 to 2.5 TSF Lab Test: MC = 25% LabTest: MC;10% test pit walls standing, no caving 2- 3- 4- 5- 6- 7- 8- 9- 10- 11 - 12- 13- 14- 15- 16- 17- 18- 9'l 9.2 93 $4 SILIY CLAY; brown to red brown, (medium stiff to stift), very n:oist, trace sand, fractured, somewhat friable, trace fine roots SAND; brown to red brown, (medium dense), moist to very moist, line to medium beames gray beames very moist gray with red brown staining Bottom of test pit at l3 1/2 foot depth. Completed and bacffiilled on 4/2295 600 Winslow Way Bainbridge lsland FAX:(206) 842-379t7 DATE 4122t93 ELEVAIION (FT)221t2 FIGURE A-8 PR(\IECTN('93386-5 East wA 98110Jt lto#;-.-mrcs rnc-'7 MB BUs: (2oo) B4z'oots C TEST PIT LO G TP'g E*,#,y,t:aw**M,!,t'{l&**ffi"wyr.w,s,s,i# l! o u.lo alrlJo- =U' Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITTONS: Sod, grasses DESCRIPTION TOPSOTL: SnTSAND TO SANDY SILT dak brown, (toose), moist, fine roots, abuMant oryanics COMMENTS Granite boulders, tine roots to 3 1/2'depth, Test: MC = 2f/" PP = 2 to 2.5 TSF clean sand and gravel podcets at 4'to 4 1/2' depth east end of test pit Lab Test: MC = 25% PP > 4.5 TSF rough digging, gravel, cobbles on top ol sand test pit walls standing, no caving 1- 3- 1- 5- 7- 8- 9- 't0 - 11 - 12- t3- 14- 15- 16- 17- 18- $1 9,2 CLAYEY SILTTO CUY; brown to red brown, (medium stift to stiff), moisl, trace to little sand, tnce gravel, upper I 12' fdable, be@mes stilfer @ depth variable fine sand layer 2'to 6'thid< top of clay varies from 3 l/2' to 4 1/2'depth fpm west to east end of test pit CLAY: light gray brown, (very stiff to hard), slightly moist, massive SAND; gray, (medium dense), moist, fine to medium Bottom of test pit at l0 foot depth. Completed and backfilled on 4/2793 600 Winslow Way Bainbridge lsland FAX: (206) 842-3797 EastwA 98110 DATE 4t22t93 ELEYATIOI{ (FT} 21 FIGURE A-9 P8q'ECT I{C'93386-5 lr. Muers t Eioognarrrrcs rnc.'f MB BUS: (206) 842€073 ( TEST PIT LOG TP'10 -wisa,r'ffi,anffim*ffsn# E Fo.ulo @ UJ o- =o 91 92 93 Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Sod, grasses DESCRIPTION TOPSOIL: S|TSAND; dark brown to black, (loose), very moist, abundant organics, fine roots, ahtndant roots l/4'tol/2'diameter COMMENTS LabTest: MC = 15o/" trace fine roots Lab Test: MC = 13% PP = 2.0 to 2.5 TSF LabTest: MC = 29% PP > 4.5 TSF SAND; Iight gray aN red brown npttled, (loose), very moist, little silt CLAY; light gr4y brown, (very stiff to hard), moist, massive upper l/2' (Z'to 2 l/2'depth) mottled and weathered Bottom of test pit at 6 foot depth. Completed and backfiiled on 4/22/95 600 Winslow Way East Bainbridge lsland WA 98110 FAX: (206) 842-s797 DATE 4t22t93 EI.EYAITCTN (Fr)17 1t2 FIGURE A-10 PROJECT ilO 93386-5* Itlt:ll"mrcsrnc.'7 MB BUS:(206) B4zaors C TEST PIT LOG TP.l1 F;E:#,y,8:r:WApE,!c.i?,Hrj;Em?#iffiHlf gr# Port Townsend New Middle School Site TEST PIT LOCAilON: See Ftgure 2 SURFACE CONDITTONS: Sod,grasses Flr Fo.ulo CDIIJJo- =cD TOPSOIL: SILTY SN,ID; dark brown to black, (bose), wet, abundant fine roots and small roots (t/4' diameter), abuMani orgaiics, trace gnvel DESCRIPTION OLAY; lrght gny brown to red brown, stighily nptiled, (very stiff to hard), moist to wet beames gray, (h?rd), ttpist, massive @ S,depth 9AND AND GRAVEL; gray, (dense), very moist, trace sift at times, cemented 1- 6- t3- 15- 10 11 12 17 18 2 3 4 5 7 I I 4 6 9r 9.2 93 Bottom ot test pit at 7 foot depth. compteted and backtitted on 4/2zg7 COMMENTS Lab Test: MC = ZBo/o PP = 2.5 to 4.5 TSF Lab Test: MC = 27% LabTest: MC = B/" occasionalabbles and 2" to 4'diameter gravel, mostly fine gravel 18'diameter boulder 600 Winslow Way East Bainbridge tshnd WA 99110 FN(: (206) 842-3797 OATE 412?,93 ELEVATK'N (FT)17 FIGURE A-11 PAq'EGT NO 93386-5 * lt-o':;='.mrcs inc.'7 MB BUS:(206) B4z-607s (-e TEST PIT LOG TP-12 H*#a,lr:a:,4*;:yin,!,.trffi,$t'ffi,g:r*w,tr*# E Guto QlrJJo- =U' Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Sod, grasses DESCRIPTION TOPSOIL: SITLY SA^ID TO SANDY SILT; dark brown to black, (bose), very moist, abundant oryanics and fine roots, ocasional roots to l'diameter COMMENTS LabTest: MC = 25% LabTest: MC = 27% PP = 4 to 4.5 TSF PP > 4.5 TSF 9r 92 2'to 4" lense of gray, silty sand, north end ol test plt only CLAY; red bown and gray brown mdfled, (very stifQ, very moist, true fine toot&, somewhat friable bemmes light gray brown, (hard), massive Bottom of test pit at 6 1/2 foot depth. Completed and backtilled on 4/2283 600 Winslow Way East Bainbridge lsland WA 98110 FA"\: (206) 842-3797 DATE 412U93 ErEYArlo}l(Ff]17 FIGURE A-12 PR(\,ECIM)93386-5It ltl",:f,,arnrcs inc.'7 MB BUS: (206) 842€o7s -i (.,_ TEST PIT LOG TP- 1 3 H,,s,w.#J:;:ffi,tpt*,!,!r:#,&nffi#:rnwssiw F.TL o-ulo out o. =ln Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDTTIONS: Recent\flll, trace vegetatlon DESCRIPTION FILL: SILTY SAND TO SANDY SILT bnwn, (loose), very moist to wet, trace to little gravel, trace clay COMMENTS LabTest: MC=20/" 'PP = 1.5 7gP' strcng sulfur odo| trace cobbles PP = 2.5 7gP Lab Test: MC = 23%, Attb Lab Test: MC = 28/" Lab Test: MC = l4/" 16" diameter boulder t- 2- 3- 4- 5- 6- 7- 8- 9- 10- fi- 12- 13- 14- 15- 16- 17- 18- 9'l s-2 93 94 95 FILL: CLAY: blue gray and bnwn and redbrown, (sottto stiff), wet, TOPSOIL: SILIY S/d,ID TO SANDY SILT; dark brown to black, (loose), very moist, tnce gravel, abundant organics and tine roots grades to SILW SA ID; gray (loose), very moist to wet, trace gravel CLAY: light gray to red brown mottled, (medium stitf to stift), very moist to wet bemmes light gray brown, (very siln, moist, massive becomes (hard) Boftom ot test pit at I 1/2 foot depth. Completed and backtilled on 4/2283 600 Winslow Way Bainbridge lsland FAX: (206) 842€797 DATE 4t2?/93 ELEVATTON (Ft)2s 1t2 FIGURE A-13 PRO'ECT NO 93386-5 East wA 98110* ltffif,."mrcsrnc. '7 MB BUS:(2o6)0424073 e T E ST P I T L O G T P' 1 4 ag,str,tr E:r:w*?* *v'*&,t":H,&Evffi#mwffi,i,w FIL Fo.luo atut o. =@ Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Sod, grasses DESCRIPTION TOPSOIL: Srtry SAND; dark brown to black, (loose), very moist, Iittle oravel COMMENTS LabTest: MC = 2l% fine roots LabTest: MC = 10/o Lab Test: MC - 3/", GS some caving, upper 2'to 3'of sand with gravel PP > 4.5 TSF clay on east end of test pit only 3- 4- 5- 6- 7 I 9 10 11 - 12- 13- 14- 15- 16- 17- 18- 91 92 93 g4 SIL7Y SA tD W|TH GRAVEL; red brown, (loose to medium dense), mo.ist SANO WTH GRAVEL; brown to gray brown, (loose to medium dense), moist, trace silt @ times, occasional abbles East end of test pit only, CLAY; Iight gny brown, (very stitt to hard), moist, trace organics and organic partings, massive, highly irregular surface sand becomes gray clay extends across the majority ol the bottom of test pit @ 8'depth Bottom of test pit at 10 foot depth. Completed and backfilled on 4/2?93 600 Winslow Way Bainbridge lsland FAX:(2ct6) 842-3797 East wA 98110 DATE 4t2?/93 ELEVAIFil(FO 33 FIGURE A-14 PROJ€CT}IO 93386-5* ltl:""F-mics rnc. '7 MB BUS: (206) 842€073 a C TEST PIT LOG TP- 1 5 EE #,y.8:71frw,#,y#,!c'i?:H,&Esffi#ww##w Ftr Fo.ulo olrJ o. =U, Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Sod, grasses DESCRIPTION t,hct Sod TOPSOIL: SILTy SN,ID; dark brcwn to black, (loose), nr.ist, little gravel, abundant tine roots 2" to 6' silty sand layer; (loose), moisl,little to some gravel COMMENTS fine roots LabTest: MC = 15% trace fine rcots caving LabTest: MC = 5%, GS highly irregular surface l- 2 3 4- 5- 6- 7- 8- 9- 10- 11 - 12- 13- 14- 15- 16 17- 18- 91 92 SAND; red brown to brown to gtay, (very loose to loose), npist, trace to little gravel increasing gravel, (loose) CLAY; light gray brown, (very stiff to hard), slightly moist, massive Bottom of test pit at I foot depth. Completed and backfilled on 4/22/93 600 Winslow Way Bainbridge lsland FAX:(206) 842-3797 East wA 98110 OATE 412U93 ErEVAnOlr IFT)291t2 Fl(iURE A-15 PROJEGT IIO 93386-5J" lto#;=..mrcs rnc.'l MB BUs:(206)842€o7s TEST PIT LOG TP-16 q{{:H,:#,ffi#ffi"mv&tlct tl oltr.''rd;uAorlttots LabTest: MC - 13% LabTest: MC = 11% LabTes!; MC = 5% A B??"H,ili3'i!'H#fi1%u"o FAX: (206) 842-5797 To iteSoIohSceIddIMewNdnsenw grassesSod,rtoP CONDITlONS:SURFACE TEST PIT LOGATION:See flgure 2 @ul o. =4U' TLt' o-ulo rootg,fineabundant SAND;S'LTY finegravel,fttlemoist,dense),mediumto(oosebrcwn,red SAND; btown, (loose b medium dense)' moist' tine to medium grading to fine to coarce SAND WITH GRAVEL; brown' (medium densQ' moist foot dePth. ComPleted and backfilled on 4/22/93 Bottom of test Pit at 6 1/2 94 91 92 93 6- 11 - 12 13 2 3 4 5 7 I 9 4 16 7 8 DATE 4123193 24fi- s*:,*l.H:csin* 933€ TEST PIT LOG TP'17 Hnw#;''p:aw*:y#{s'#,!&**yffii#m*"!irsi*H Flr Fo- UIo CNtU o- =o Port Townsend New Middle School Site TEsr PIT LocAnoN: See Flgure 2 SURFACE coNDtTtoNS: Sod, grasses DESCRIPTION TOPSOIL: SILTY SN,|D; dark bpwn , (loose), moist, abundant tine roots COMMENTS Lab Test: MC - ll% slight caving LabTest: MC = 4% abundant 1'to 2' size gravel 91 92 SILTY Sr'f,,lD WTH GRAVEL; red brown and brown, (medium dense) , moisl SAND WITH GRAVEL: gray to brown, (medium dense), moist SAND;gray, (loose to medium dense), moist SA JD WTH GRAVEL; gray, (medium dense), nnist increasing coarse gravel GRAVEL WITH SAIIID; gray to dark gray, (medium dense), moist Boftom of test pit at I toot depth. Completed and backfilted on 4/22/93 600 Winslow Way Bainbridge lsland FAX: (206) 842-3797 EastwA 98110 DATE 4t23t93 ELEYATION IFN 231t2 FIGURE A-17 PRO'ECT NO 93386-5 l.l. Muers f*;:l#l*csinc' (- TEST PIT LOG TP-l 8 e Port Townsend New Middle school site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Sod, adiacent to stockplle Flr o. UJo alrjJo- =an DESCRIPTION TOPSOTL: CLAY SILT dark brown, (medium stitf , very moist, abtMant fine toots , organics, tnce sand blocky fraclure grades to-CLAY: tight gny brown, (very stiff to hard), moist' massive mottled; (sttft), very. moist,CLAY;brownredandtobrowndarklightgraygray triablewhatgmeofofineclaytracetoots,upwr SAND fO SAND W\TH SILT brown to dark red brwn' (dense to very dense), very moist becomes light gray brown, moist, fine PP = 2.5 TSF LabTest: y6 = 25% LabTest: y6 = 24% PP=3to>4.5TSF LabTesl: MC = lglo, GS tittle gravel 4' to 4 1/2' depth, cemented COMMENTS 9l 92 93 Bottom of test pit at 9 1/2 foot depth' Completed and backfilled on 4/22/93 2- 4- 6- 5- 18- 11 14 l6 17 3 5 8 I 10 2 3 7 600 Winslow WaY Bainbridge lsland FAX: (206) 842-3797 EastwA 98110 DATE 4123193 E-rvelox(rr)19112 FIGURE A-18 PeqrecrHo 99386-5* ltl",=rllamrcs inc. '7 MB BUS: (206) 842€073 a(^\_. TEST PIT LOG TP'l I w{,trffi,s*yn#mw,ffiw FtrriFo.ulo CNlrJ o.E o Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Sod, grasses DESCRIPTION TOPSOIL: SILIY SN{D WITH GRAVEL; dark brown to black, (loose), moist to very moist, wlth abundant fine roots COMMENTS Lab Test: MC = |f/o 'occasional nbbles Lab Test: MC - 3% occasional mbbles l0'to 12'diameter 1- 2- 3- 4- 5- 6- 7- 8- 9- 10- 1l - 12- 13- 14- 15- 16- 17- 18- 91 s-2 93 SAND WITH GRAVEL; red brown, (loose to medium dense), mois| fine toots beames gray brown Bottom of test pit at 10 foot depth. Completed and backfilled on 42293 600 Winslow Way Bainbridge lsland FAX: (206) 842-3797 EastwA 98110 DATE 4t23t93 €LEVArx)rl(FD 18112 FIGURE A-19 PR(UECT IIIO 93386-5 lr Muers fr Er-oognarnrcs rnc.'7 MB BUS: (206) s42ao7s e TEST PIT LO G TP-20 Hs,wf:Elw##&*,w,,#,ffi#mwffiw 600 Winslow Way East Bainbridge lsland WA 98110 FAx: (206) 842-5797 OATE 4123t93 ELEVAITTN (Fr)241t2 FIGURE A-20 PRq'ECT IIO 93386-5 IL TFo.uto atrlJo- =U, 9t 92 93 Port Townsend New Middle School Site TEST PIT LOCATION: See Ftgure 2 SURFACE CONDITIONS: Sod, grazed grasses DESCRIPTION TOPSOTL: SAND TO SILTY SAND; dark brown to btack, (oose), npist abundant fine roob, trace to liile organkx COMMENTS LabTest: MC = t5% significant caving to 6 foot depth Lab Test: MC = 6%, GS Lab.Test: MC = 4/o some red brown slreaking hard clay chunks 3'to 4' long @ 6'to 7' depth denser, rough digging SAND; light brown, (loose to medium dense), moist to slighily moist, fine to medium, trace sift grades to tine to aarse sand;brown to gray, (medium dense), moist to slightly moist becomes gray brown with gravel Bottom of test pit at 10 foot depth. Completed and backfiiled on 4/22/95 tF lt-::l=..mrcs inc.'7 MB BUS: (206) B4z-607s TEST PIT LOG TP-19 waffii,r,*ffi#lnw,irsn# Ft.l. o. UJo U'IIJ o. =a 91 92 93 Port Townsend New Middle School Site TEST PIT LOCATION: See FlCIure 2 SURFACE CONDITIONS: Sod, grasses DESCRIPTION TOPSOIL: SILTY SAl,lD WITH GRAVEL; dark brown to black, (toose), moist to very molst, with abundant fine roots COMMENTS Lab Test: MC = |f/o occasional cobbles Lab Test: MC = 3% occasionaigDbbs 10'to 12'diameter SAA/D WITH GRAVEL; red brown, (loose to medium dense), moisL fine roots beames gray brown Bottom ot test pit at l0 foot depth. Completed and backfilled on 4/2293 600 Winslow Way Bainbridge lsland FAX: (206) 842-3797 EastwA 98110 DATE 4123193 ELEVATTOil (Fr)181t2 FIGURE A-19 PRqJECT 1{O 93386-s* lt-o':l=.-mics inc.'7 MB BUS: (206) 842-6ots EC T E ST Pl T LO G T P-20 -isw.usxa:*tyisa*,ifiia**'ntr:rtr"wffi# Flrt'l-o.uto @ul o.E o Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Sod, grazed grasses DESCRIPTION TOPSOTL: SAND TO SILI/ SN'ID; dark bnwn to black, (loose), npist, abundant tine roots, trace to little organics COMMENTS LabTest: MC = 15% significant caving to 6 foot depth Lab Test: MC - 6/", GS Lab Test: MC = 4% some red brown streaking hard clay chunks 3'to 4' long @ 6'to 7' depth denser, rough digging 91 s-2 s-3 SAND; light brown, (loose to medium dense), moist to slighily moist, fine to medium, trace silt grades to fine to aarse sand; brown to gray, (medium dense), moist to slightly moist beames gray brown with gravel Bottom of test pit at 10 foot depth. Completed and backfilled on 4/2293 600 Winslow Way East Bainbridge lsland WA 98110 FAX: (206) 842-3797 OATE 4123193 EtEVArpil(Fr)241t2 RGURE A-20 PRqJECT NO 93386-s Ll Mgers !f Biodgnamics inc. ' 7 MB BUs: (206) s4z{o7s (-a TEST PIT LOG TP'21 ws*s.t:i:ffi,##&tr#,&#ffi#mwrsi# Flr o-ulct v,IIJ o- =o 91 92 s-3 s-4 Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDffiONS: Sod, grazed grasses DESCRIPTION TapSotL: stLw sN\tD; dark brown to black, (loose), moist abundant line toots, trace to little organics COMMENTS trace cobbles Lab Test: MC = 20% 'LabTest: MC = 9% abundant cobbles @ base of topsoillayer Lab Test: MC = 7%, GS red brown streaks, caving trom 2'to 8'depth Lab Test: MC = 4/o SILIY SAND AND GRAVEL; light gray brown, (dense), moist, occasional cobbles, cementd SANO TO SAND WITH SILT; brown to light gray brown, (loose to medium dense), moist,.fine to medium becomes light gray to gray Bottom of test pit at 13 toot depth. Completed and backfilled on 4/22/93 600 Winslow Way Bainbridge lsland FAX: (206) 842-s797 EastwA 98110 DATE 4t23t93 ELEVATpI(FT)331t2 FKiURE A-21 PRO'ECT NO 93386-5It ltH:fi"mrcsrnc.'7 MB BUS: (206)842€o7s (-c T EST PIT LO G TP -21 gls:#.y;',:s,g,.,apg',!,trffi,,x,ffi#w.w,treig_ t-l! o. uJo anlrJ GE o Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Sod, grazed grasses DESCRIPTION TOPSOIL: SILTY SAND; dark brown to black, (bose), moist abundant fine toots, trace to little organics COMMENTS trace cobbles LabTest: MC = 20% LabTest: MC = 9% abundant abbles @ base of topsoil layer LabTest: MC = 7%, GS red brown'stre aks, cavi ng from 2'to 8'depth LabTest: 1'tr6 = 4% 1- o- 3- 4- R_ 6- 7^* 8- I 10- 11 - 12- 13- 14- 15- 16- 17- 18- 91 92 g3 $4 SILTY Sr'f,lD AND GRAVEL; light gray brown, (dense), moist, oeasional cobbles, cemerrtd SAND TO SAND WITH SILT brown to light gny btown, (loose to medium dense), mois[ fine to medium becomes light gray to gray Bottom of test Sit at 13 foot depth. Completd and backtilled on 4/22/93 600 Winslow Way East Bainbridge lsland WA 98110 FAX: (206) 842-3797 OATE 4123t93 EI^EYAIION(FD 331t2 FIG]URE A-21 PR(I'ECT NO 93386-5 * lt::l='-mtcs Inc. '7 MB BUS: (206) 842€o7s TE ST P I T LOG T P -22 w,w,gsa:'mitv,*,!,.i?,m,ffivfi#wwtrs,i# E Fo-IUo outJo. =(D Port Townsend New Middle School Site TEST PIT LOCATTON: See Flgure 2 SURFACE CONDITIONS: Sod, grazed grasses DESCRIPTION TOPSOIL: SILIY SAND; darkbawnto black, (loose), npist,little gravel, abundant line roots COMMENTS occasional mbbles LabTest: MC = 18% trace fine roots LabTest: MC = 8/o, GS PP> 4.5 TV = 1.8 TSF Lab Test: MC = 21o/" slight caving 1- 2- 3- 4- 5- 6- 7 8- 9- 10- 't1 - 12- 13- 14- 15- 16- 17- 18- 91 $2 93 s-4 95 $6 SILTY SAND WTH GRAVEL; Iight gray brown, (medium dense to dense), very moist to wet, trace clay CLAY; light brown to light gray brown, (very stitf to hard), moist, trace gravet SAND; brown to light gray brown, (medium dense), moist, tine grades to SAND;dense), moist, trace gravel, tine to coarse CLAY; light gray brown, (very stifl to hard), moist, trace gravel, trace organics and organic partings, massive Zones of clay with little sand and graveland occasionalcobbles Sand and Gravel pocket, east side of test pit Bottom of test pit at ll 1/2 foot depth. Completed and backfilled on 4/23/93 600 Winslow Way Bainbridge lsland FAX: (206) 842-3797 East wA 98110 OATE 4123193 ELEYAnOI (FT)21 1t2 FKiURE A-22 PRqIECTM)93386-5* ltH:il-mrcsrnc.'7 MB BUs:(206)s42€o7o C TE ST PI T LOG TP'23 w#H;:ffi#wl,'r{mffiffi#lrustr## FTL o.uto alll o. =o 91 92 $3 s-4 Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Sod, grazed grasses DESCRIPTION TOPSOIL: SILIY SA tD TO SANDY SILT; dark brown to red brown and dark brown, (loose), abundant fine roots and trace organics, occasional large roots COMMENTS LabTest: MC = 22/o west side to test pit trace seepage at base of sand with gravel pocket Lab Test: MC = 2V/" PP = 2.0 to 2.5 TSF TV = 1.25ISF PP > 4.5 TSF TV = 2.9 75P 2'to 4' layer (with 12" to 24'thick pocket @ middle of tesl pit), SAND WITH GRAVEL; gray, (loose to medium dense), trace to litile silt AaU_; light gray and red brown mottled, (stif2, very moist grades to light gray brown, (very stiff to hard), moist to very moist, trace organics, trace o rga nic partings, massive very moist to wet Bottom of test pit at 10 foot depth. Completed and backfilted on 4/23/93 600 Winslow Way Bainbridge lsland FAX: (206) 8424797 DAT€4123t93 ELEVATIOI{ (FI) 31 1t2 FIGURE A-23 PROJECT I{O 93386-s EastwA 98110 lr. Muers # Erougnarnrcs urc.'7 MB BUS: (206) 842-6ots CC TEST PIT LOG TP'24 -wwatr*&wffiffiffi"H,;,rsng_ Ft!t'Fo' UJo alrl o-E U, Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Sod, grazed grasses DESCRIPTION TOPSOIL: SILTY SAND TO SANDY SILT dark brown to brown, (bose), moist, ahtndant fine roots, trace to little gravel COMMENTS Lab Test: MC = 18% LabTest: MC = 2V/" PP > 4.5 TSF TV = 1.9 TSF rough digging 1- J- 4- 5- 6- 7- 8- 9- 10- 11 - 12- t3- 14- 15- 16- 17- 18- 91 92 s-3 94 SILIY CLAY; red brown and gray brown, (stiff to very stiff), moist, trace roots CLAY; light gray brown, (very stiff to hard), moist, massive SAND; gray, (dense), moist, fine little gravel Bottom of test pit at 10 toot depth. Completed and backfilled on 4/23/93 600 Winslow Way Bainbridge lsland FAX: (206) 942-3797 DATE 4123193 ELEVATK'N (FI)321t2 FICiURE A-24 PRqtECr ilO 93386-5 East wA 98110 Cr Muers f Eroognamlcs lnc. '7 MB BUS: (206) 842€073 :T LOG TP-24 Port Townse nd New Midd le School Site Sod,grasses SURFACE PIT LOCATION : See Flgure 2 ;olL: SILTY SAND TO SANDY SLLT; daribrown b brown' (toose)' line toots,tace to little Y CLAY; red brown and gray brown' (stttf to very stlll' moist' tnce toots tY: Iight graY brown' (vei o,u b hard)' moist' na$ive .ND; gra|,(dense)' moist' fine ft gravel Bottom of test plt at 10 foot dePth'and backfilled on 4/23/93 B'"?#jE'ST''H#fi11u"0 F/\x: (2oo) 8424797 DATE 4/23/93 32112 LabTest: P16' = 18% LabTest: tr116 = 27% PP > 4.5 TSF'TV = 1.9TSF rough digging FlGURE A-24 93386'5 MB H,?".lftamics inc' BUS: (206) 8426073 EC T EST P I T LOG TP-25 EE #,tr t:i:wntv#s;ir,wt&E#,m.wffi# Fll Fo.ulo ou, o- =6 Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Sod, grazed grasses DESCRIPTION 4'TOPSOIL: SILTY SN,ID: dark brown, (loosd, moist, abundant fine roots COMMENTS sand variable thidcness LabTest: MC = 9% top of clay inegular at 18" to 28" depth LabTest: ti7 = ZZ% 2- 3- 4- 5- 6- 7- 8- 9- l0- 11 - 12- 13- 14- t5- 16- 17- 18- 9r $2 SAND; red brown to dark brown, (loose), moist,little silt, fittle fine roots CLAY; red brown to light gray brown, (stitf to very stiff), moist to very moist, trace organics aN organic partings, blocky fracture grades to ft1ht gray brown, (very stitf to harO, moist, massive Bottom of test pit at 7 foot depth. Completed and backfilled on 4/23/93 600 Winslow Way Bainbridge lsland FAXr (206) 84247st7 East wA 98110 OATE 4t23t93 ELEYAIK'N (FTI 24 FICURE A-25 PRO'ECT I{O 93386-5* lt3:;-'.mrcs rnc.'7 MB BUs:(206) 842€o7s TEST PlT LOG TP'26 Eew,y,yr:r,w,tpw{sWwttrsi# ll.t'Fo.ruo aIU o. = Ch Port Townsend New Middle School Site TEST PIT LOCATION: See Flgure 2 SURFACE CONDITIONS: Brush DESCRIPTION 6' FOREST DUFF: dark brown, (very [oose), organic material COMMENTS LabTest: MC = 19% PP = 2.5 to 3 TSF TV = 1.0TSF PP > 4.5 TSF TV > 2.5TSF 1- 2- 3- 4- 5- 6- 8- 9- 10- tl - 12- 13- 14- 15- 16- 17- 18- 91 TOPSOIL: SILIY SAND; red brawn to dark brown, (loose), very moist, trace to little gravel, abundant roots 1/4'to 1/2'diameter CLAY; light brown to red brown, (stitt to very stiff), moist to very nnist, occasionalroots beames light gray, trace organhs and organic partings, massive, blocky tracture at times Bottom of test pit at I foot depth. Completed and backfilled on 4/23/93 600 Winslow Way Bainbridge lsland FAX: (206) 842-37tt7 East wA 98110 OATE 4123193 ELEVAIION (FT) 21 FIGURE A-26 PRq|ECTIIC)93386-sJF ltl"":F-mrcs inc-'r MB BUS: (206)842{073 (-C APPENDTX B i Middle School93386-5 May 21, 1993 Appendix APPENDD( B LABORATORY TESTING A laboratory testing program was performed to evaluate the index properties of the site soilsand provide a correlation with geotechnical engineering parameters. Laboratory testswere performed on disturbed soil samples collected from the test pit explorations. Thelaboratory testing performed and procedures followed are presen-ted below. AII testing wasperformed by Soil Technolory of Bainbridge Island, Washington. Tests were conductedin general accordance with the American Society of Testing and Materials (.{STM) standard test procedures. ; SOIL CI,ASSIFICATION Soil samples were collected during the exploration program and were visually classifiedin the field. Field visual classification of soils was conducted in general accordance withASTM D-2488 "Standard Practice for Description and Identification of Soils (Visual- Manual Procedure)". Field log soil classifications were updated as necessary based on theresults of the laboratory testing. MOISTURE COIVTENT (MC) Moisture content detcrminations were performed on the majority of site soil samples ingeneral accordance with ASTM D-22L6. The results of these tests are presented on the testpit logs in the comments column and are also shown on Table Bl presented below. GRAIN SIZE ANALYSES (GS) The Iaboratory testing program consisted ofgrain size analyses ofselected site soil samples to determine grain size distribution. Selected samples are indicated on the test pit logs in the comments column. Sieve analyses of particles greater than the U.S. No. 200 mesh sieve size were performed. The tests were conducted in general accordance withASTM D-422. The results of the grain size analyses are shown in this appendix on FiguresBl through B3. ATTERBERG LIMITS (AtIb) Liquid and plastic Atterberg limits were determined for selected samples of the fine grained, cohesive soils encountered in the explorations. The tests were performed in accordance with ASTM D-4318 to aid in classification and correlation with engineeringparameters of the soils. The results of the Atterberg limits tests are shown on Figure B-4. Myers Biodynamics, Inc. Middle School93386-6 May 21, 1993 Appendix Test Pit TP.1 TP.1 TP.1 TP.1 TP-2 TP.2 TP.2 TP.2 TP-3 TP-3 TP-3 TP.3 TP.4 TP.4 TP-4 TP-4 TP-5 TP.5 TP.5 TP.5 TP.6 TP-6 TP-6 TP.7 TP.? TP-7 TP.8 TP-8 TP-9 TP.9 TP.10 TP.1O TP.10 TP-11 TP-l1 TP.11 TP.12 TP-12 TP.13 TP.13 TP.13 TP.13 TP.14 TABLE 81 MOISTURE COMTENT TEST RESULTS Samgle Depth (feet) Moisture Content (7o) s-1 s-2 s-3s4 s-1 s-2 s-3 s-5 s-1 s-2 s-4 s-5 s-1 s-2 s-3 s4 s-1 s-2 s-3 s-5 s-1 s-2 s-3 s-1 s-2 s-3 s-2 s-3 s-1 s-2 s-1 s-2 s-3 s-1 s-2 s-3 s-1 s-2 s-1 s-2 s-3 s4 s-1 1.0 - 3.0 - 4.0 - 7.0 - 0.5 - 2.0 - 3.5 - 8.5 - 1.0 - 3.0 - 5.0 - 11.0 - 0.5 - 2.0 - 4.5 - 8.5 - 1.0 - 3.5 - 4.5 - 6.5 - 2.0 - 4.0 - o.D - 0.5 - 2.0 - 4.0 - 1.0 - 4.0 - 1.5 - 5.0 - 0.0 - 1.5 - 3.0 - 0.5 - 2.0 - 4.0 - 0.5 - 2.0 - 0.0 - 2.5 - 4.0 - 4.5 - 0.5 - 2.0 4.0 5.0 8.0 1.5 3.0 4.0 9.0 2.0 3.5 6.5 11.5 1.0 2.5 5.0 9.0 3.0 4.0 5.0 7.0 3.0 5.0 7.0 1.0 2.5 4.5 2.0 5.0 2.0 6.0 0.5 2.0 4.4 1.0 2.5 5.0 1.0 2.5 1.0 3.5 4.5 5.0 0.?5 14a z3nnI 4 11 8 7 31 5 ul u] 6 31 15 t5n 30 15 2L % 16 2L 5 % 10 % % 15 utn %n 8 %nnaau 2l Myers Biodynamics, Inc. Middle School May 21, 1993 Appendix e3386-(^ TABLE 81 MOISTURE COI.IITENT TEST RESULTS (Continued) Test Pit TP.14 TP.14 TP.15 TP.15 TP.16 TP.16 TP-16 TP.17 TP.17 TP.18 TP-18 TP-18 TP.19 TP.19 TP.2O TP-20 TP.2O TP.21 TP.21 TP-21 TP.21 TP.22 TP.22 TP.22 TP.23 TP-23 TP-24 TP-24 TP.25 TP.25 TP-z6 Sample s-2 s-3 s-1 s-2 s-1 s-2 s-3 s-1 s-2 s-1 s-2 s-3 s-t s-2 s-1 s-2 s-3 s-1 s-2 s-3 s-4 s-1 s-2 s-3 s-1 s-3 s-1 s-2 s-1 s-2 s-1 Depth (feet) 0.75- 1.0 2.0 - 3.0 0.5 - 1.0 3.0 - 4.0 0.5 - 1.0 1.0 - 2.0 3.0 - 4.0 0.5 - 1.0 2.5 - 3.0 1.0 - 2.0 3.0 - 3.5 4.5 - 5.0 0.5 - 1.0 1.5 - 2.0 0.5 - 1.0 2.0 - 2.5 4.0 - 5.0 0.5 - 1.b 1.0 - 2.0 2.5 - 3.5 12.0 - 13.0 0.5 - 1.0 1.0 - 2.0 3.0 - 3.5 0.5 - 1.0 3.0 - 4.0 1.5 - 2.0 3.5 - 4.0 1.5 - 2.0 3.0 - 4.0 0.5 - 1.5 Moisture Content (7o) 10 3 15 5 ut 11 b 11 4 % 2t ilt 16 3 15 6 4n 9 7 4a 8 2Lnnan 9n 19 Myers Biodynamics, Inc. Locotion: PORT TOWNSEND MTDDLE SCHOOLDote : Wed Moy 05 1993No.MYERS BIODYNAMICS 93386-5J-344ProjectProjectGrain SizeAnalysisSoilTechnology, lnc.U.S. STANDARD SIEVE SIZE11 ,t0 ,2o ,10 '160 ,too l2oo ,4oo100I09080F070td=coE.trJ 50zf,240LrJOSroo-102030405060708090100otrjzFbJE.Fztd()ELrJ(L20l00looo 500loo 50to51o.5GRAIN SIZE IN MILLIMETERS0.1 o.05o.ol 0.005o.oolINXtI\Ta\\tLI\*\\\il\!\'tll.\^5q\ililSILT OR CLAYSANDFINE.o*rrlMEDIUMGRAIELFINECOARSEco8ELESSymbol++€}.Boring NoTP- ITP-2TP-5Somple Nos-1s-2S-lDepth Filenome1.0-2.0 fr TPls-l2.0-3.0 fr TP2S-2r.0-3.0 ft TPss-lClossificotion r/ DescriptionSM Silty sond with orovelSM Siltv sond with 6rovetSM Silty sond with irovelFigrrre B1lItfII1 Project ; MYERS BIODYNAM|CS 9JJB6-5Project No.: J-344Locotion: PORT TOWNSEND MTDDLE SCHOOLDote : Wed Moy 05 1993Grain SizeAnalysisSoilTechnology, lnc.l01009080F670UJ=(D(rtrJ 50zf,240td()ffiro(L20lootooo 5001oo 50U.S. STANDARD SIEVE SIZEl. ,to l2o l1o 160 ltoo ,2oo l4oo510.5GRAIN SIZE IN MILLIMETERSo.l o.o5o.ol 0.005102030otrJ40zFtrJ50EFzIJ60pLdo_708090100o.oori!iit;-l=rtlItil-!-ttit\\tTij.\L\(! lLtril:li\ki*P\1- - ".SILT'OR CLAYSANDFINEMEDIUMCOARSEGRAVELFINECOARSECOEBLESSymbol+-#+Boring No.TP- I4TP-I5TP- I8Somple No.s-3s-2s-3Depth2.0-3.0 ft3.0-4.0 fr4.5-5.0 ftFilenomeTP I 4S_3TP I 5S-2TP I85-3Clossificotion r/ DescriptionSW Well-groded sond with orovelSP Poorli qroded sondSP-SM Poorly iroded sond with siltFigure 82)I Project : MYERS BI0DYNAMICS 95386-5Project tiio.: J-344Locotion: PORT TOWNSEND MTDDLE SCHOOLOote : Wed Moy 05 1993Grain SizeAnalysisSoilTechnology, lnc.o.5.U.S. STANDARD SIEVE SIZE,1 ,t0 l2o ,40 ,60 ,too ,2oo ,4oo10090800r02030405060708090F6totJ=(DE,lrj 50zf,240trJotrro(L20otrjzaF-trJEFzUJC)u.trJo-100100lo0o 500loo 50to51o.5GRAIN SIZE IN MILLIMETERS0.I o.05o.ol 0.005.0.001I\\tiltil\tl\1.\\Il.tsaISILT OR CLAYSANDFIN€.oorselMEDIUMGRAVELFINECOARSECOEBLESSymbol+-&+Boring No.TP-20TP-21TP_22Somple No.s-2s-3s-2Depth Filenorne2.0-2.5 il TP20S-22.5-3.5 ft TP2lS-32.0-2.5 ft TP22S-2Clossificotion / DescriptionSP Poorly qroded sondSP-SM Poorly 6roded sond with siltSM Silty 'so-nd with grovelFj-gure 83l Soil Technology, lnc Project : MYERS BIODYNAMICS 9JJ86-5 Project No. : J-344 Locotion : PORT TOWNSEND M|ODLE SCFTOOL Dote : Wed Moy 05 1993 100 90 20 r0 010203040 Symbol Borlng No. Sarnple No. PLASTICITY CHART 50 60 70 80 90 100 Water Content ln percant Llqutd pbstic Natural 'Limlt umlt 31 23 23 1 10 120 130 140 r50 Plaslicity lndex Oescripdon (USC) 80 o- 70 d60oz. Fo640 Jo- Jo 0 2,n& 50 39 42 s-4 s.3 s.2 o A o TP.3 TP.1 TP.13 27 192 Fat Clay (CH) Lean Ctay (cL) Lean Clay (CL) Figure 84 C APPENDIX C Middle School May 21, 1993 Appendix e3386-/ APPENDTX C INFILTRATION TESTING The EPA methodology used the field investigations of soil permeability is called thefalling head test procedure. The falling head procedo"" *,", performed at the test sitesusing the following steps: Jdentify study area. Percolation tests were performed within the areas indicated to ourfirm as possible stormwaterinfiltration areas. Tests were located in each of the foursiteareas indicated. Prepaiation of Test Hole. The infiltration test hole was prepared by digging or hand - augering to the indicated elevation of the proposed infiltration system oi "iUt a limiting(restrictive) soil horizon was encountered. Logr of the infiltration test holes or.r" prep"ftdand are presented in Table Cl. The diameter of the test holes was generally 6 inches. Toexpose a natural soil surface, the sides of the hole were scarified and the loose soil materialwas removed from the bottom of the test hole. Two inches of 1J2 to 3/4 inch gravel was placedin the test hole to protect the bottom from scouring action when the water wis added. Soakine period. The hole was filled with at least 12 inches of clear water. This depth ofwater was maintained for at least 4 hours or in some cases overnight if clay soils werepresent. In sandy soils with little or no clay, soaking was not necessary. If after filling the holetwice with 12 inches of water, the water seeped completely away in iess than teri minutes,the test proceeded immediately. Measurement of the Infiltration Rate. Except for sandy soils, infiltration ratemeasurements were made 15 hours but no more than 30 hours after the soaking periodbegan. Any soil that sloughed into the hole during the soaking period *r", ,"--oi.d and thewater level is adjusted to 6 inches above the gravef(or g inches alove the bottom of the hole).At no time during the test was the water level allowed to rise more than approximately 6inches above the gravel. Immediately after adjustment, the water level was measuredfrom a fixed reference point to the nearest V8 inch at 30 minute intervals. At least three testmeasurements were taken. After each measurement, the water level was readusted to the 6 inch level. The last waterlevel drop was generally used to calculate the percolation ratp. In s.andy soils or soils inwhich the first 6 inches of water added after thi soaking period seepd away in less than iOminutes, water level measurements were made at 10 minute intervals for a t hour period.The last water level drop was used to calculate the percolation rate. Calculation of the Percolation Rate. fire percolation rate was calculated for each test.hole by dividing the time interval used between measurements by the magnitude of the lastwater level drop. This calculation resulted in a percolation rate in tcrms of minutes perinch. Example: If the last measurement drop inwater level after 30 minutes is b/8 inch,the percolation rate = (30 minutes)/(V8 inch) = 48 minuteVinch Myers Biodynamics, Inc. e3386-d'a'Middle School May21,1993 Appendix InfiItration Test Number IT.1 TT-2 IT.3 IT-4 TABLE C1INFILTRATION TEST LOCATION SOIL LOGS Port Townsend School District Proposed Middle School Site Depth(inches)Soil Descriptipn (USDA) 0-4 4-2t 2A-49 4)-55 G15 L5-25 25-39 39 -46 0- 16 16-20 n-u 34 -36 0-12 p-n TOPSOIL SILT LOAM TO CLAY LOAM; red brown and light gray mottled, (very stiff), moist, trace roots CLAY; gray, (very stiff to hard), moist to slightly moist SAND; red brown, (dense), very moist, cemented TOPSOIL: LOAMY SAND; dark brown, (loose), moist, fine roots, trace gravel LOAMY SAND; red brown to dark gray, (loose to medium dense), very moist, trace gtavel CLAY LOAM TO CLAY; gray brown,(stiff), moist SAND; gray brown and red brown, (loose to medium dense), moist TOPSOIL: GRAVELLY SANDY LOAJvI; dark brown, (loose), very moist GRAVELLY SANDY LOAM; gray brown, (dense), very moist, cemented GRAVELLY SANDY LOAM; lightgray brown, (medium dense), very moist to wet from 30 - 34 inches CLAY LOAM; brown to red brown, (medium stiff to stift), very moist TOPSOIL: GRAVELLY LOAM TO GRAVELLY SANDY LOAM; dark brown, (loose), moist, abundant gravel at 12 inches depth GRAVELLY SAI',IDY LOAM; brown to dark brown, (medium dense to dense), moist CLAY LOAIvf; light gray to red brown mottled, (stiff;, moist, trace gravel Myers Biodynamics, Inc. 29 -35