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HomeMy WebLinkAboutWWP2702291_4Group Northwest, Inc. Geotechnical Engineers, Geologists & Environmental Scientists » ` m.' FINAL REPORT GEOTECHNICAL ENGINEERING STUDY CEDAR RIVER TRUNK RELOCATION PROJECT PHASE -II NORTH THIRD STREET ROUTE RENTON, WASHINGTON Job No. G-0346 Prepared for MUNICIPALITY OF METROPOLITAN SEATTLE (METRO) September 10, 1993 Geo Group Northwest, Inc. 13240 NE 20th Street, Suite 12 Bellevue, WA 89005 Phone: (206) 649-8757 I UMI Group Northwest, Inc. September 10, 1993 Parametrix, Inc. Attn: Ms. Vicki Sironen P.O. Box 460 1231 Fryar Avenue Sumner, WA 98390 SUBJECT: FINAL REPORT Dear Ms. Sironen: Geotechnical Engineers, Geologists & Environmental Scientists Job No. G-0346 GEOTECHNICAL ENGINEERING STUDY CEDAR RIVER TRUNK RELOCATION PROJECT, PHASE -II NORTH THIRD STREET ROUTE RENTON, WASHINGTON We are pleased to summit this report titled "Geotechnical Engineering Study, Cedar River Trunk Relocation Project, Phase -II, North Third Street Route, Renton, Washington." This report is prepared under a Multi -Disciplinary Engineering Services Agreement (Contract No. CS/M32-91 B, Work Order #15) between Parametrix, Inc. and the Municipality of Metropolitan Seattle (METRO). Geo Group Northwest, Inc. is a subconsultant to Parametrix, Inc. under the same agreement to perform geotechnical engineering study for the proposed trunk relocation Phase -II project. Our study included subsurface exploration along the proposed trunk alignment and review of available soil and groundwater information in the subject area. Six test borings were drilled in July 1993 along the alignment for the purpose of this study. It was revealed that the soils were of three general types: brown to tan sandy silt to clayey silt (recent fill), dark gray interbedded clayey silt and silty fine sand (alluvial deposits in the Lake Washington and the Cedar River), and olive gray to gray gravelly sand to sandy gravel (glacio-recessional outwash). Based on the preliminary design provided to us and the soil and groundwater conditions in the area, we concluded that the site is generally suitable for the proposed construction, however, the soils underneath the pipe invert between Stations 0+50 to 11 +00 are liquefiable 13240 NE 20th Street, Suite 12 • Bellevue, Washington 98005 Phone 206/649-8757 • FAX 206/649-8758 September 10, 1993 METRO - Cedar River Trunk Relocation G-0346 Paee 2 during earthquakes. The liquefaction potential should be mitigated before placing the pipe. Trench excavation requires shoring between Stations 0+50 to 10+00 and between Stations 16+50 to 22+50 where utilities are located too close to the excavation. Trench boxes may be used in other areas where utility lines are not to be affected by the excavation. Shoring may be implemented with conventional metal sheet piles either driven or vibrated into the ground. Groundwater is expected to be encountered during the trench excavation between Stations 0+00 and 11 +00. Dewatering may be required if groundwater hinders pipeline installation. The detailed discussions and recommendations are presented in the text of this report. We appreciate the opportunity to have been of service to you on this project. Should you have any questions regarding this report or need additional consultation, please feel free to call us. Sincerely, Geo Group Northwest, Inc. W" t"_� Dalong Huang, P.E. ti1NM C� Staff Engineer V of WASH, h 0 William Chang, PE. �'� bUAL Principal I EXPIRES 2/ 191 9¢ I Geo Group Northwest, Inc. N i TABLE OF CONTENTS JOB NO. G-0346 Page 1. INTRODUCTION................................................... 1 1.1 Project Description ........................................... 1 1.2 Scope of Services ............................................ 2 2. SITE CONDITIONS ................................................. 2 2.1 Surface Condition ............................................ 2 2.2 Site Geology ................................................ 3 2.3 Subsurface Conditions ........................................ 3 2.4 Groundwater ................................................ 4 3. DISCUSSION AND RECOMMENDATIONS ............................... 4 3.1 General .................................................... 4 3.2 Seismic Considerations ........................................ 5 3.3 Trenching Methods and Trench Stability ........................... 6 3.4 Trench Shoring .............................................. 8 3.5 Bedding and Trench Backfill................................... 10 3.6 Dewatering................................................ 11 3.7 Street Pavement ............................................ 11 4. LIMITATIONS.................................................... 12 ILLUSTRATIONS Figure 1 - Vicinity Map Figure 2 - Cedar River Trunk Alignments Figure 3 - Exploration Plan Figure 4 - Site Plan and Soil Profile, Stations 0+00 to 14+00 Figure 5 - Site Plan and Soil Profile, Stations 14+00 to 28+00 Figure 6 - Soil Pressure Diagrams for Shoring Designs Figure 7 - Illustration for Pile Embedment 77-: _ 4 p v REFERENCES 1. "Engineering Report, Cedar River Trunk Relocation Project, Phase II", Metro Engineering Services Divisions, May 1993, (ARMS number A65021; Task number Y75). 2. "Final Geotechnical Study, Cedar River Trunk Sewer Realignment Project, Second Avenue Route and Construction Bypass Route, Renton, Washington", Golder Associates Inc., November 22, 1991. 3. "Well Field Monitoring Study" prepared for the City of Renton by CH2M Hill, June 1988. 4. "Preliminary Geologic Map of Seattle and Vicinity, Washington", H. H. Waldron, B. A. Liesch, D. R. Mullineaux, and D. R. Crandell, published by the U.S. Geological Survey, 1962. 5. "Cedar River Trunk Relocation Phase 2, Plan and Profile" with shifted trunk alignment, provided to us by Ms. Mann -Ling Thibert, August 1993 APPENDIX A Field Subsurface Exploration Program Plate Al - Boring Log 1 Plate A2 - Boring Log 2 Plate A3 - Boring Log 3 Plate A4 - Boring Log 4 Plate A5 - Boring Log 5 Plate A6 - Boring Log 6 Plate A7 - Boring Log 7, by Golder Associates Inc., 1991 Plate A8 - Boring Log 8, by Golder Associates Inc., 1991 9 GEOTECHNICAL ENGINEERING STUDY CEDAR RIVER TRUNK RELOCATION PROJECT PHASE -II NORTH THIRD STREET ROUTE RENTON, WASHINGTON Job No. G-0346 1. INTRODUCTION 1.1 Project Description The Cedar River Trunk Relocation Project is located within the City of Renton in the vicinity of the interchange of Interstate 405 and State Route 169 (Maple Valley Highway) as shown in Figure 1 - Site Vicinity Map. The relocation project will reroute a portion of the existing 42 inch diameter Cedar River Trunk to provide a minimum clearance of 200 feet around the City of Renton water production wells, and replace the existing concrete pipe with poly -lined ductile iron pipe. The new pipeline will be approximately 5,000 feet long and constructed in three phases according to METRO's engineering report (Reference 1). Phase -I of the project was completed in 1991. For Phase -II, the METRO Engineering Services Divisions conducted a cost/benefit and environmental impact study on six alternative routes in May 1993. The study recommended North Third Street route as the best of the six alternatives. The North Third Street Route, as shown in Figure 2 - Cedar River Trunk Alignments, starts from the east end of North Brooks Street west to Factory Avenue North, turns north on Factory Avenue North to North Third Street, then turns west onto North Third Street, and continues westward to the existing Eastside Interceptor at Burnett Avenue North. METRO provided us with a copy of the preliminary plans for the Phase -II trunk relocation project, including design plans and profiles, as shown in Figures 4 and 5. The preliminary design indicates that the bottom elevation of the pipeline will be placed at elevations of 11 to 12 feet below the existing ground surface except between Stations 0+00 and 0+50 where the inverts are designed at about 24 feet below the existing ground surface. The pipeline is designed at a slope of 0.3% from Station 0+50 to Station 28+00 (end of the Phase -II project). The trunk alignment shown in Figures 4 and 5 has been shifted toward the center of North Third Street as indicated in Reference 5. r i. J' METRO Letter of Transmittal 821 Second Ave., M.S. 117, Seattle, WA 98104-1598 (206) 684-1298 To L�-f1Q r 5`i5T&M PIVIP"J �UBLie G•>oa9 DcPAR ?rl9-7,,T moo Mt�� AUK . S. RFtiI o o " We are sending you the following: Z Attached ❑ under separate cover Date 9 /z I l 93 File/Contract No. To Attention Of A11112 Regarding Copies Date Drwg. No. Description ' /21 Iq3 l i— INAL ,�E�oIZ % C7�oTEcj��v/ CAL IE--Y✓4Z. STvl-/ ��o�K r2►v icy k These are transmitted Remarks ❑ For approval For your use and information ❑ As requested ❑ For review and comment ❑ Other Signature `_ //X�� -� it Division 04, 1, September 10, 1993 G-0346 METRO - Cedar River Trunk Relocation Page 2 1.2 Scope of Services This study was conducted under a Multi -Disciplinary Engineering Services Agreement (Contract No. CS/M32-91 B, Work Order #15) between Parametrix, Inc. and the Municipality of Metropolitan Seattle (METRO), under which Geo Group Northwest, Inc. is a subconsultant to Parametrix, Inc. The purpose of this study is to characterize the subsurface conditions at the site, perform engineering analyses, and develop geotechnical recommendations on the design and construction of the Phase-ll trunk relocation project. This report will address the following issues in accordance with our proposal approved by METRO: • Site Conditions, including surface, subsurface and groundwater; • Trench excavation and shoring requirements; • Shoring design parameters; • Groundwater and dewatering issues; • Seismic consideration and potential pipe settlement; • Trench bedding, backfill and compaction requirements; • Street pavement; • Construction related issues. 2. SITE CONDITIONS 2.1 Surface Condition The subject site is located in a well developed urban area within the City of Renton. As shown in Figures 2, 4, and 5, the rerouted trunk alignment is mainly along North Third Street between Burnett Avenue North and Factory Avenue North. Two short portions of the trunk are located along Factory Avenue North and North Brooks Street. North Third Street is an arterial street with one way traffic to the east and residential buildings on the two sides. The ground surface along the entire Phase -II alignment is covered with asphalt pavement. The elevation of the ground surface at Station 0+00 is currently 29 feet based on the datum shown in Figures 4 and 5. The ground surface elevation gradually increases along North Third Street to 35.3 feet at Station 22+15, and to 38.2 feet at Station 28+00. Geo Group Northwest, Inc. L. September 10, 1993 METRO - Cedar River Trunk Relocation 2.2 Site Geology G-0346 Pace 3 The site geologic condition was mapped by H. H. Waldron, B. A. Liesch, D. R. Mullineaux, and D. R. Crandell in "Preliminary Geologic Map of Seattle and Vicinity, Washington", published by the U.S. Geological Survey in 1962 (Reference 4). Available subsurface information includes groundwater conditions studied by CH2M Hill for the City of Renton's aquifer protection zone in June 1988 (Reference 3) and soil conditions explored by Golder Associates Inc. for Phased of the same project in November 1991 (Reference 2). The project site is located on the south end of Lake Washington and northeast side of the Cedar River. During the last glacial recession, the prehistoric Cedar River channel discharged a large flow of gravelly sand to sandy gravel into the lake, namely Glacio-Recessional Outwash. Lake Washington originally drained to the south through the Black River. In the late 1800's the Mountlake Cut was constructed connecting Lake Washington with Lake Union and lowered Lake Washington to its current level. Prior to the lowering of the Lake, much of the area around the current southern end of the Lake including much of north Renton was under water. Over the years, clayey silt and silty fine sand materials were brought to the lake by the flow from the Cedar River forming alluvial deposits. Since the lake water was lowered to its current level, large amounts of soil was moved to the area during site development and construction activities. Artificial soils in the area consisted of sandy silt to clayey silt. Although the soils at the site can be categorized into three geologic units, the soil conditions are complex due to the manner in which the alluvial soils are deposited. The soils are laid down as the river meanders across the river valley. The soils deposited are dependent on the speed of the river flowing in the valley. High energy rivers deposited gravel and coarse sand while low energy rivers deposited silt and fine sand. 2.3 Subsurface Conditions Our site exploration was conducted from July 8 to 12, 1993 with six test borings in the locations indicated in Figure 3 - Exploration Plan. Boring 1 (B-1) was drilled to a depth of 34 feet and B-2 to B-6 were drilled to a depth of 26 feet. A groundwater monitoring well was installed in each of the borings. The details of the field exploration, including drilling method, Geo Group Northwest, Inc. pr September 10, 1993 G-0346 METRO - Cedar River Trunk Relocation Page 4 soil sampling, field testing and monitoring well installations, are recorded in Appendix A - Field Subsurface Exploration Program and Boring Logs. The soil and groundwater conditions encountered in the six borings are presented on Plates A2 to A7 in Appendix A. Two boring logs that were recorded by Golder Associates Inc. in 1991 are also included in the appendix as Plates A8 and A9. Due to the complexity of the geologic conditions, soil stratification can not be extrapolated between the test borings. The soils encountered along the alignment are of three general types: brown to tan sandy silt to clayey silt (recent fill), dark gray interbedded clayey silt and silty fine sand (alluvial deposits in Lake Washington and the Cedar River), and olive gray to gray gravelly sand to sandy gravel (glacio-recessional outwash). 2.4 Groundwater Groundwater was encountered in all of the six test borings during the time of drilling between July 8 and 12, 1993. The groundwater levels are indicated in the boring logs in Appendix A and Figures 4 and 5. The water levels in Golder's Boring 7 and 8 were measured at 16.7 feet and 17.2 feet, respectively. The current groundwater levels are higher than the pipeline bottom elevation near B-1 and B-2, close to the bottom elevation near B-3, and below the bottom elevations near B-4 through B-8. The subsurface soil at the site is part of the Cedar River aquifer used by the City of Renton to provide water for the City. The groundwater conditions in the project area were studied by CH2M Hill for the City of Renton in 1988 to determine the aquifer protection zone. Groundwater levels are generally lower in the summer and higher in the winter due to higher water levels in the Cedar River and less water pumped from the aquifer. Groundwater is expected to be present during the construction of the pipeline. 3. DISCUSSION AND RECOMMENDATIONS 3.1 General Based on the results of our field exploration and available subsurface information, it is our opinion that the subject site is suitable for the proposed construction, However, the soils Geo Group Northwest, Inc. a Fj September 10, 1993 METRO - Cedar River Trunk Relocation G-0346 Page 5 underneath the pipe invert is liquefiable between Stations 0+50 to 11 +00. Measures should be taken to protect pipes from liquefaction damage. The pipeline alignment has been shifted toward the center of North Third Street since our draft report was submitted. The change in alignment will place the proposed pipeline farther from the existing underground utilities and structures. This report addresses the conditions affecting the pipeline to be placed near the center of North Third Street. Based on available soil and groundwater information, it is our opinion that temporary shoring is necessary in some sections to protect existing utilities, while trench boxes may be used in other sections where utilities will not be affected by the excavation. The current groundwater levels exceeded the bottom elevations of the trench between Stations 0+00 and 10+00. Water is expected to be present during construction. If groundwater imposes difficulty in the pipe installation, dewatering measures should be taken to control the groundwater levels during construction. We recommend that the contractor be responsible for shoring, dewatering, controlling settlement and other construction related issues. The information and opinions in this report should be provided to the contractor as information only. It is the contractor's responsibility to interpret the information and implement the construction methods. 3.2 Seismic Considerations We conducted analyses on soil liquefaction potentials along the pipeline alignment according to the published research data and our experience in the region. For a one hundred year earthquake, a magnitude of 7 and a peak ground acceleration of 0.2 g were used in our analyses. The results are as follows: From Stations 0+00 to 0+50, the pipe invert is to be on the dense sandy gravel layer. Liquefaction potential is minimal in the section. From Station 0+50 to 11 +00, the pipeline is to be on the loose silty sand and medium stiff sandy silt layer below the groundwater. The soil under this section of the pipeline is subject Geo Group Northwest, Inc. 4 1 0 � 12 =-j September 10, 1993 METRO - Cedar River Trunk Relocation to liquefaction during a 100-year earthquake. G-0346 Paee 6 From Station 11 +00 to 28+00, the pipe invert is to be on the medium dense sandy gravel above groundwater. Liquefaction potential of the soil below the pipeline in this section is negligible. Measures to reduce potential damage to the pipeline include lowering the pipeline elevations, installing supporting piles to transmit pipeline load to deeper denser soil, and replacing the liquefiable soil with crushed rock. We understand that Metro is interested in replacing the liquefiable soils with crushed rock. It should be noted that the thickness of the liquefiable soils is 7 feet below the pipe invert near Station 1 +60 and Station 5+40, and 4 feet near Station 11 +00. We recommend 2" to 4" size crushed rock be used as the replacement and a layer of geotextile be placed underneath the crushed rock as illustrated in Figure 8. 3.3 Trenching Methods and Trench Stability The installation of the proposed pipeline requires trench excavations up to 24 feet deep. Possible trenching methods include: (1) open cut with 1 H:1 V side slopes; (2) braced or cantilevered sheet pile shoring, (3) excavation with trench box shoring, (4) excavation with metal plate shoring braced with hydraulic jacks. The suitability of the above measures depends on the excavation depths, type of soils, and groundwater levels during excavation. The following is a brief discussion on these trenching methods: (1). Open cut with 1 H:1 V side slopes. Open cuts with a slope of 1 H :1 V are considered acceptable for temporary slope stability during construction. An unshored trench is only feasible in areas where structures and utilities are located at a horizontal distance to the excavation farther than the vertical distance to the excavation bottom and groundwater is below the bottom of the trench. (2). Braced or cantilevered sheet pile shoring. Metal sheet pile shoring can be used to protect the existing ground utilities, street, and private properties adjacent to the excavation. It laterally supports the two sides of the excavated trench and protects the soils from sloughing and collapsing, therefore minimizing the potential ground Geo Group Northwest, Inc. September 10, 1993 G-0346 METRO - Cedar River Trunk Relocation Page 7 settlement and property damage. The sheet piles can be either driven into the ground with a impact hammer or with a pneumatic vibrator before the excavation starts. Cantilevered sheet pile walls may be implemented if the trench is shallower than 15 feet, otherwise, braced sheet pile walls should be designed. If braced walls are designed, braces are installed from the top row down as excavation progresses. (3). Trench box shoring. A trench box is optional in the areas where soils can stand vertically for a short time before the trench box is lowered down to protect soils from sloughing. Depending on the duration of the construction and the time the cut can stand vertically, pea gravel may need to be placed to fill the gaps between the box and the trench sides. This is important because loose soil sloughing into the gaps will cause unwanted street settlement and increase the construction costs for repairing the street pavement. Instead of using a trench box and filling gaps with pea gravel, metal plates may be used in conjunction with hydraulic jack braces to provide shoring to the vertical excavation. This shoring system followa the same construction procedures as does trench box shoring. The stability of excavated trench depends on the exact soil and groundwater conditions encountered during excavation, and depends on the construction procedures. Soils expected to be encountered include a majority of loose soft to medium stiff silt and fine sandy silt from Stations 0+00 to 11 +00, and medium dense to dense sandy gravel from Stations 14+00 to 28+00. The contractor should be aware that any deep excavation in these soils has potential problems associated with cut instability and ground settlement around the excavation. To evaluate the stability, we recommend that the contractor excavate a test trench in the areas where open trench excavation is to be conducted and determine construction procedures to minimize construction risk. Potential settlements of the pipeline, existing utilities and streets due to construction activities have been of concern to the METRO engineers. It should be mentioned that there are always settlements associated with underground excavations. The magnitude depends on the method of excavation, soils, and groundwater, etc. The site has a high potential for ground settlement caused by construction activities due to the nature of the soils. The settlement potential can be minimized by good construction management and procedures. Geo Group Northwest, Inc. q J J I a September 10, 1993 METRO - Cedar River Trunk Relocation G-0346 Paee S The contractor should be aware that excessive machine vibration at the site can density the sandy soils and consequently cause pipeline and street pavement settlements. In the area where no sheet pile shoring is installed, street settlement could occur due to soil lateral movement toward excavation. The contractor should keep construction traffic as far as possible away from the excavated areas. We recommend that a survey plan be established to document the site conditions before, during, and after the pipeline construction. This is to avoid possible future disputes due to the deep excavation in a residential area. Reference points should be set up along the trench to monitor the ground settlement on a daily basis during construction. METRO should establish criteria on the allowable settlements on the street pavement, and allowable pipe settlement, such as 1 inch maximum settlement within 20 feet. If excessive settlement is monitored, construction work should be immediately stopped for examination. Necessary remedial measures should be taken before resuming the construction. The survey should also include the houses along the two sides of the pipeline alignment. 3.4 Trench Shoring As a general rule, trench shoring is required to protect structures and utilities that are located at a horizontal distance to the excavation less than the vertical distance to the excavation bottom. An unshored trench may be excavated in the areas where structures and utilities are located at a horizontal distance to the excavation farther than the vertical distance to the excavation bottom, however, trench boxes should be used to prevent soil sloughing and provide safety for the workers. Based on the shifted pipeline alignment in Reference 5, the following conditions are applicable: Stations 0+00 to 0+50 The pipe invert will be 24 feet below the street level. Groundwater is expected to be present at the time of construction. Shoring is required due to the deep excavation and high groundwater level. We recommend that braced sheet pile shoring walls be designed for this section. Stations 0+50 to 10+00 Liquefiable soil will be excavated and replaced with crushed rock in this section. The total excavation will be about 19 feet deep. Groundwater is expected to be Geo Group Northwest, Inc. W7 F - September 10, 1993 METRO - Cedar River Trunk Relocation G-0346 Paee 9 encountered in the excavation. Existing underground utility lines are located within 9 feet of the two sides of the trench. Metal sheet pile shoring is recommended for the excavation in this section. Stations 10+00 to 16+50 The proposed pipe invert will be up to 13 feet deep. The current groundwater level is 1 to 2 feet below the pipe invert. Groundwater may or may not be encountered in the excavation depending on the groundwater levels during the construction. Existing underground utilities are 7 to 11 feet from the proposed trench. Open trench excavation may be conducted in this section, however, a trench box or metal plates braced with hydraulic jacks should be used as discussed in Section 3.3. Stations 16+50 to 22+50 The proposed pipe invert will be up to 13 feet deep. Groundwater is not expected during excavation. Existing underground utilities are located at 3 to 5 feet from the trench. Metal sheet pile shoring is recommended for this section of the trench. Stations 22+50 to 28+00 The proposed pipe invert will be about 12 feet deep. Groundwater is not expected during excavation. Existing underground utilities are 7 to 11 feet from the proposed trench. Open trench excavation may be conducted in this section, however, a trench box or metal plates with hydraulic jacks should be used as discussed in Section 3.3. The design soil lateral pressure is as follows: Cantilevered Sheet Piles (without braces): • Active soil pressure above groundwater: 45 pcf equivalent fluid pressure; • Active soil pressure below groundwater: 25 pcf equivalent fluid pressure; • Passive soil pressure above groundwater: 250 pcf equivalent fluid pressure; • Passive soil pressure below groundwater: 130 pcf equivalent fluid pressure. • Groundwater pressure should be added if the groundwater levels on the two sides of the wall are different, as shown in Figure 6. Braced Sheet Piles: • Active soil pressure is designed as rectangular distribution of 30 pcf times the wall Geo Group Northwest, Inc. -71 it September 10, 1993 G-0346 METRO - Cedar River Trunk Relocation Page 10 height H; • Groundwater pressure should be added if the groundwater levels on the two sides of the wall are different, as shown in Figure 6. Two feet of soil weight may be applied to the street surface as equivalent construction vehicle loads. 3.5 Bedding and Trench Backfill The pipe invert should be placed on firm native soil. Any liquefiable soils should be over - excavated and replaced with either crushed rock or clean gravel materials. We recommend that crushed rock of size 2 to 4 inches be used in the area where groundwater is to be encountered. A layer of geotextile, such as Mirafi 500X, should be placed underneath the crushed rock to separate the rock from the native soils. Any soft soil should also be over - excavated and replaced with gravel or crushed rock. The bedding materials around the pipe can be either minus 3/4 pea gravel with no fines passing US Sieve 200 or controlled -density fill. If controlled -density fill is to be used as bedding material on top of the crushed rock, a layer of geotextile should be used between the two materials. A typical trench section is shown in Figure 8. Backfill is the material used to fill the excavated trench. We recommend that the soils excavated from the trench be exported from the site and be not used as backfill due to the high fine particle content and high moisture content. These types of materials require a high energy compactor which could cause large settlement of adjacent properties. Imported materials should be used for backfill. The import materials should consist of no organic materials and less than 5% fine grains passing US Sieve # 200. Materials such as "pit -run", consisting of sand and gravel, may be used as backfill since this type of material requires less compaction energy to achieve the required compaction. Pea gravel or controlled -density fill may also be used as backfill. Backfill other than controlled -density fill and pea gravel should be compacted to 95 percent of maximum dry density based on ASTM 698-78D (Standard Proctor). The compaction should Geo Group Northwest, Inc. September 10, 1993 G-0346 METRO - Cedar River Trunk Relocation Page 11 be conducted on fill placed at 10 inches per lift in its loose state. The contractor should avoid excessive compaction within two feet of the pipe. 3.6 Dewatering Groundwater is expected to be encountered in some areas during the construction. Dewatering may be required if water hinders the construction of the pipeline. Dewatering may be conducted by installing dewatering wells around the proposed excavation or directly pumping water from the excavated trench. Dewatering wells will depress the groundwater levels in the area and cause potential settlement of adjacent structures. Dewatering wells also interfere with the production wells since the site is located in the City of Renton's aquifer protection zone. Pumping water directly from the excavated trench is a preferred measure. It should be noted that problems associated with pumping water from an excavated trench are often bottom heaving and slope stability problems in open excavation caused by high hydraulic gradient toward the trench. A critical condition of the soils including sand piping may occur in the case of cohesionless fine sandy and silty materials. The hydraulic gradient near the trench bottom can be decreased by increasing the embedment depths of metal sheet pile walls. Sand piping may be prevented by placing crushed rock materials at the trench bottom on a layer of geotextile before starting to pump the water. The minimum embedment depth of the sheet piles should be at least 1.5 times the elevation difference between the groundwater level and the trench bottom in order to avoid the critical gradient in the soils and consequent bottom heaving conditions, as illustrated in Figure 7. It should be the responsibility of the project contractor to follow adequate construction procedures and take necessary measures to prevent sand piping, soil sloughing, and trench bottom heaving. 3.7 Street Pavement The design of the street pavement should be in accordance with the design requirements regulated by the City of Renton. Coordination should be made with the Renton Public Works Department for the design. As general guidance, we recommend the pavement design to Geo Group Northwest, Inc. September 10, 1993 G-0346 METRO - Cedar River Trunk Relocation Page 12 consist of the following: • Six inches of Asphalt Concrete (AC) over four inches of Crushed Rock base (CRB) material or over three inches of Asphalt Treated Base (ATB) material for North Third Street; • Five inches of AC over four inches of Crushed Rock base (CRB) material or over three inches of Asphalt Treated Base (ATB) material for streets other than North Third Street. 4. LIMITATIONS The recommendations are our professional opinion derived in a manner consistent with the level of care and skill in the geotechnical engineering profession in the region. Our findings and recommendations stated herein are based on the field observations, our experience and engineering analyses. This report is prepared for the exclusive use of METRO and its representatives for the subject project at the stated specific location. The actual soil conditions may vary from those encountered in the test borings. In case the soil condition varies during site excavation, Geo Group Northwest, Inc. should be notified and the above recommendation should be re-evaluated. We recommend that Geo Group Northwest, Inc. be retained to perform a general review of the final design and specifications to verify that our recommendations have been properly interpreted and implemented in the design and in the construction documents. We also recommend that Geo Group Northwest, Inc. be retained to provide monitoring services during construction to verify the design specifications and construction procedures. 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M W S < VICTORIA Q rn �` Q. _< VICTORIA ST Y SST `� j v+ oti`tt': r 163 0 3 r S 2( N D y < HSNTON Q �..:.: l 5tI6.. r S ■ 2ND S ¢ tt CEDAR R/VER y y < 2 D L = �PR�`S v� —3 f�IJ -.- az Fs PARK Cq < _ Ro O Y > > PL ST ST EN � > S 3RD < a N C 0 S a TH S �' ax-t > T k HOP = \ > PING Q N E a N CENTER >P S 5 ajµ �O� S 5TH _j ST U) a O CCU° p Q f y ? w w ti S 6TH ST S O 6TH cc ST S Cr-- ��67F ST \ � a ST S 7TH 3 ST Z g 7TH *�� wN PARK �� Q 'C ST . LW1 = w ` PHILLIP Of> 167 R R10f l <': -.,ARNOLD =a AQ ¢ 405 I F i SITE VICINITY MAP CM -Group Northwest, Ine. METRO CEDAR RIVER TRUNK Geotechnical Engineers, Geologists, 6 RELOCATION PHASE 11 Environmental Scientists RENTON, WASHINGTON SCALE NONE DATE 7/19/93 1 MADE DH CHKD WC JOB NO. G-0346 FIGURE 1 7L F -_ -N M a lat\EL IPIf L I''1;, jll, 17.1, ON F, m a m E ma E I IN 5th St l I I D I I N 4th St CST Z Z Z Z Z Z Q Q Q Q Q < n > m O O d a-N IQ U Cu LL C N 3rd St7 B I IN 2nd St �7] 1 405 ub� d Park s Cedar Rrver�` ti Park `9 MH 69 RH10-11 Replaced by Phase I LEGEND Existing Alignment Phase I Alignment (completed) Recommended Phase II Alignment Phase III Alignment �I Phase II Alternative Alignments ADAPTED FROM REFERENCE-1 Group Northwest, Inc. CEDAR RIVER TRUNK ALIGNMENTS Geotechnical Engineers, Geologists, & Environmental Scientists RENTON, WASHINGTON SCALE NONE DATE 7/20/93 MADE DI I CHKD WC JOB NO. G-0346 FIGURE 2 - F-- AF A > IF�z I F L.LJ Lj / (� 1> 1 I I I I I I I I I Q II Im, II I I II zl II Izl II I I I I I I I I I I ILjI II ILLJI II I II -J II Q II I1I IjII , II IIII J�IIIIuII II II uII II II �-III 1Iul II IIIII II II (n �IwwIL Bn - \ \\vVlllII 1' \ ��II � ♦ ♦ � ♦♦I ♦ • ♦ • ♦ I♦II III \ IIII I IIII IIII 11II 1III SEE FIGURE 4MW-11 I I I n1 •• I' LEDEND: MW-10 City of Renton Monitoring Well Location and Number 7 Boring Location & Number by Golder & Associates, 1991 B-1 Approximate Boring Location and Number by Geo Group Northwest, July, 1993 SCALE: 1=200' Q zIIIIlIIII / , / , . 4TH ST.nF-1 nF-1 ------------ I w I I I LL11 3 I > IQ a < I I I > N. MARION ST. zl I I I3:I I I I0.- F-- 1 L J I 11 I01 1 01 W MW-10) I N. 3R ST_F-'O---] F-1 J U u u B-4 I B-5 / BROOKS ST / III I I I I I I I I I I SEE FIGURE 5 I I I I I I I I I 1 II 1 uu N. 2ND ST_ n II 1 I 11 I I I� I I 11 I N I , I I I I I II 1 I I 1 1 1 I I I II I I II I 7 8 1 / I II I I II I uu F- T F II II I I , 5 4 3 2 R o I 1 3030' - 304 S 1 Iu 3 307 I I MH I ST 0 SS S P MH, 70 0 30 SHT IN \ 0 II I I N 30' 30' MANHOLE CDNN6 K, \ G O 30t - - SEE EC (TYPAB PL) TI G v I I I u 1 30' 30' ON S` O B-1 I 1 800 1 I 1° I 6 16 30' 30' _ N CYSOI 50 T O I i 1 - I 13 -- 804 1 I 10 I I N 180750 N 180750 BEGINNING OF PROJECT v1 I S. I N STA 0+00 z ,.1 ,-so �- '^ 1 I I 1 303 i o ❑ I - \ _ I I APT. BLDG. 3 230 ela 231 1 I I G _ 4I 1n z 0 G 820 G I I S 6 Iy STA5+3 I I< I OFFICEOBLDG. 32.0 _ - 243 I I I 302 I I I I i a I MH 6 C6 0 t a I O I BM 21 Sp I 301 I I 322 I STA 13+78./3 2 0 20 236 \_ M 300 U 3 I z I 234 0 30' I 3� SD 0 SD S - 239 I <I ❑1 811 --- --- - -------- - - - - - - -�-- -- ---- ------ - 1 I 8t3 I 815 B'2 O G 1N TG 6 1oao 1 -- 1zoo• 1300 V1400 t6' DENSE BRU 1 N 817 h S. - o; _�, I � MH 5- S. ----� ED MH 4 100 100 STA 10+92.94 I ' 18't STA 8+13.02 G 911 I 1009 MH 3 91 I 1201 1207 30' O 251 01 I STA 6+95.08 i -- I 250 G I 11 N t80500 I u G I 11 3 v`ni 246 i 1° II 249 r I .CHURCH I 1-STORY I 248 PLAN RESTAURANT 5o n so Irn ts0 II I I c CB °. 16 9i I I u I I BM 22 g II 33. I I I 32.6 � i N SEE TABLE 3 � U c v ON SHEET 5 bf PIPE ALIGNMENT HAS BEEN SHIFTED TOWARD STREET CENTER 30• 30' I >� 30 3� i i 16 60 n 1G e VI JOIR ,. SIN::. �max'::'y 50 50 m• � 1 I OI I N N3N IW .. : I " ;p :I:3 Lu 3 ,"V , .. 40 :�1G� ': 3 k o:"' ., lnidb� :. ; J k i° S ci _ ci . =1 . ~ IW ; wFcvlo �.1e, bibbc� c7 p br..'..' ffi� = 40 Lou W I $ 1 1 I W 1Lu °, " ' MUSM { c '' 30 30 m M - I , .. :.I',li" .. ._. .. �E?9.62:.: - IE 29:8 ... .-. ;. 7.•?':. 7.6 fi. IE 9.38 ... "IE 27-77' 4 ff -: _, I .... 1E 26.21 I` 'I f Id 26.7n. ML 25. ML i�; IE 26. I7: ... E 26.45' - .. . ' .:::: ...... E 27.00' : 26. 8' GW 1 GW 20 10 IE 17.92' . IE 25.86' s• _ - ....IM / 3 - IE I L/S- 7/16 9 I ,.. 7/16/93 I "'E 19.88' IE 0.24' FUTUR 8" PIPE M + IE 21.08• - 21. 7 16 9J _ 7 IE 19.40' - MUSM / / CONNECTION, TYP 10 _ MUPt '1 +i I GW GW 10 IE 5.12•.. _ IE 5.16'-- IE 2.3T MUPt I �1 GW T '...: 0 0 40.6 LF 4 j - - , _ i I I , 0+00 2+00 4+00 6+00 8+00 10+00 12+00 14 00 ORIGINAL DESIGN PROVIDED BY METRO ELEVATION o I Eo DESIGNED: OAIE EOIIALS IEAN �cA LEVEI. , GEO GROUP NORTHWEST INC. R uscws AB A STEB ,s°7> M-LT JUNE 93 PRE I M NARY F O 1 \ dEOTECNN1CAlENCiMEEC GEOLOGISTS.AND TR NVIRORELO RELOCATION OMwN: CHECKED' SCAM CEDAR RNER TRUNK RELOCATION � �' i DJ8 PHASE 2 Y75 N F� 0 R M AT I 0 N ONLY RECDNNENDED: NOTED SITE PLAN AND SOIL PROFILE DAW'N` NO CONTRACT NO: N REVISION BY APPD DATE AIR°�° STA 0+00 TO STA 14+00 cODRn,NAres ► BEARINGS ARC FIGURE 4 BASED ON VASNINOTQ/ CO- piBINATE SYSTEM NORTH 2O14: - — I II I O 23 N 1210 i •C,1 4, w_ 0 _ 12 1204 I 121 }p} I ABANDO ED 1 II MH 7 ~INII �'3 303 1504 1500 2WAT O i;oA 18+20.81 1308 1311314 0 300 I I I S b, S. 1 _-- U _---- SD —tJ__—' u e 12"W c7 12"AC J w- ' 12 SO W w w - 6"W n 12"AC 14 W 15+t6 00--- - ----_'—--'_'—_ -- G ;� - —�—G— B� ------_- " G- N 3 RD STREET J�a U r i o B-4 48-1 / 2 G MH 8 -Il247 STA 21+01.03 If 1 N G 1201 1207 1211 APT. BLDG. I I I I I I 11 248 }, 251 I : I I U H 1421 APT$. ® w 51 I _ �1 3 9 STA 34.40 STA N 160500 I I 35.9 33. I 8I z 1503 1507 1 APT. BLDG. I M I o I < 2479. I BM 7 � N Q ,I z l 5 S 241 I SEE TABLE 3 ON SHEET S z < I 11 I O TYP 251 o b I b I z37 N +I M 206 yo / 3 30' _ w M 247 16' 30 1 30' -35 I 204 2 P N; _ M 200 3! 241 1510 gRpS c�6 PIPE ALIGNMENT HAS BEEN SHIFTED TOWARD STREET CENTER I 9 229 yyM 233 ! S - I g 50 w S O 225 I _ N 26 00 ' BROOKS ST - — DD� / \�-24 SO o V CB ry +80250 g so PLAN - _ D 60 100 150 o I I �—j1 IL._!I 221 I o _ _ N B-7 _ _ B-0 C N ' MH 10 120 PROTECT � MH ,11! S FH STA 25+28. 2 DUNN LUMBER CO. TREES (IYP�`. 5TA- + g —�PE 0250 o o FEET o I ; o / CB DE�GSE. RUSH 60 n j z z n n o I L`N 60 0 �INQ 5o i N 'I� I� D7 N sn'�w a'IN of U �_ m 0 a 0 -- 50 I W It{ Io I —� W - — ap Wa S Lu D W O 40 3 3 U• 3 .. - O C3 U 0 In 1 10 ' io . O _ W H. N 3 �D 1D H U 1/! i 1 W ��>:T 1� Im N S to rc c� — a o Cz _ I - m a m a 10 i-- I a➢ , MUSM MUSM �_ 30 E za.24- I ML/SM I 30 I 1 1E 30,89' I IE 19.92' MUSM :IE 30.9T - I — J_� _ I IE 31.00 IE 30.4T IE 10 GW/GP 26.2b' I IE 2D.IS4' I .-- 7/16/93 I I T' 7/16/93 1 - - 2 GIN - 7/16/97 I _ 1E 24.}uJ 7/16/93 GW IE 2 °J �-- -- --_ - . _. .. _ -- IE 23.26' !. ,._ I MUSM MUSM MUSM 1 ML/SM 10 yd j I- 1 0 0 i I I 14+00 16+00 18+00 20+00 22+00 24+00 26+00 28+00 ORIGINAL DESIGN PROVIDED BY METRO EVATID! DN 100 MEAN sG LEVEL, 1 ' DSttGi (ADJUSTED 191n �71 DESIGNED: M-LT GEO GROUP NORTHWEST, INC. GEOTECIINIGL ENGINEERS, GEOLOGISTS AND ENVIRONMENTAL SCIENTISTS SCALE: CEDAR RIVER TRUNK RELOCATION PWOSE 2 wre: JUNE 93 FZi NO - Y75 PRELIMINARY � O R _ DRAWN CHECKED: DJB INFORMATION O N LY J NOD SITE PLAN AND SOIL PROFILE ICONTRACT N0 STA 14+00 TO STA ZH+OO `�"'"°'�° APPROVED, No. REVISION BY APP'D DATE COIII DDNTES t BEARUKS IRE OtD11MR S SRM�N�TN�20rE FIGURE s Sheet Pile Wall Trench Bottom PASSIVE SOIL PRESSURE= 250 PCF EFP. Surcharge = h feet of soil Street Surface H ACTIVE SOIL PRESSURE= 45 PCF EFP D 250D, psf 45(D+H+h), psf G.W. Figure 6a - Cantilevered Sheet Pile Wall with Groundwater Level below Sheet Pile Tip Sheet Pile Wall Trench Bottom 250(D1) ge = h feet of soil h Street Surface H D1 - G.W. 45(D1+H+h) D2 250(D1)+130(D2), psf 45(D1+H+h)+25(D2), psf Figure 6b - Cantilevered Sheet Pile Wall with Groundwater between Trench Bottom and Pile Tip Surcharge in feet of soil Sheet Pile Wall Street Surface H1 ACTIVE SOIL PRESSURE = 45 PCF EFP 45(H 1 +h) ' G.W. Trench Bottom H2 G.W. � ACTIVE SOIL PRESSURE = 25 PCF EFP; SOIL PRESSURE WATER PRESSURE = 130 PCF EFP; D = 62.4 PCF WATER PRESSURE = 62.4 PCF Water ressure 130(D) +64.2(D), psf 45(H1+h)+25(H2+D)+62.4(H2+D), psf Figure 6c - Cantilevered Sheet Pile Wall with Groundwater above Trench Bottom Surcharge in feet of soil If groundwater is above trench bottom, add the following triangular water pressure to the wall. T V G.W. 62.4(H1), psf See Figure 7 for minimum pile embedment depth. Figure 6d - Braced Sheet Pile Wall G246FIG.XLS C: U14M8LMP0RnG146PIG7 A7S Shoring Walls, Cantilevered or Braced. 2 TO 4 INCH SIZE ROCK. IF NEC H1 D Figure 7 - ILLUSTRATION FOR MINIMUM PILE EMBEDMENT (for the case of groundwater above the trench bottom) Notes: 1. In order to reduce the instability due to heave or critical sand condition in the trench bottom, a minimum of embedment depth of the sheet piles should be designed. 2. The minimum embedment D should be 1.5 times the original groundwater height over trench bottom, i.e.: D = 1.5( H1) 3. In order to reduce the risk of sand piping in the trench bottom, a layer of geotextile may be placed on the excavated trench bottom before bedding materials is placed. 4. Pumping water from the trench should not be started until the geotextile and bedding materials are placed on the bottom. ILLUSTRATION FOR PILE EMBEDMENT Group Northwest, Ine. METRO CEDAR RIVER TRUNK Geotechnical Engineers, Geologists, & RELOCATION PHASE II Environmental Scientists RENTON, WASHINGTON SCALE NONF DATE 9/ )!9 i MADE UI I CHKD WC JOB NO. G-0346 FIGURE ? 1 F- L C:l 4AM"PORPGC146PIGS ATF SHORING WALL IS REQUIRED WHEN UNDERGROUND UTILITIES ARE TO BE AFFECTED BY EXCAVATION G.W. y IF GROUNDWATER IMPOSES DIFFICULTY IN PIPE INSTALLATION, DEWATERING IS NECCESSARY PAVEMENT BACKFILL, SUCH AS "PIT RUN" MATERIALS, COMPACTED TO 95% OF MAXIMUM DRY DENSITY. BEDDING MATERIAL: CONTROLLED DENSITY FILL OR MINUS 3/4" PEA GRAVEL, TO COVER A MINIMUM 120-DEGREE SEGMENT OF THE PIPE BOTTOM. 7-4" SIZE CRUSHED ROCK TO REPLACE LIQUEFIABLE OR SOFT SOIL IF NECCESSARY GEOTEXTILE A TYPICAL TRENCH SECTION Group Northwest, Inc. METRO CEDAR RIVER TRUNK Geotechnical Engineers, Geologists, & RELOCATION PHASE II Environmental Scientists RENTON, WASHINGTON SCALE NONE DATE 9/9/93 1 MADE DH CHKD WC JOB NO. G-0346 FIGURE 8 r i _ C _ a 30 1 * y y APPENDIX A Field Subsurface Exploration Program and Boring Logs Geo Group Northwest, Inc. i - � � � -- - � Subsurface Exploration Program Our field exploration was conducted between July 8 and July 12, 1993 with six test borings along the pipeline alignment. The borings were drilled by Environmental Drilling, Inc. of Everett, Washington under the supervision of a field representative from Geo Group Northwest, Inc. The locations of the borings are shown on Figures 3, marked as B-1, to B-6. The drilling was conducted with a truck -mounted drilling machine. A continuous flight, hollow stem, 4.25 inside diameter, auger was used in the drilling. Standard Penetration Tests (SPT) were conducted and soil samples were taken at each 2.5 foot interval. The SPT was performed in accordance with ASTM D1586-84. A 140 lb hammer was used to drive a 2-inch outside diameter split spoon sampler 18 inches into the ground with a dropping distance of 30 inches. SPT blow counts were recorded for each six inches of sampler penetration. The blow counts for the last two six inch increments were added to obtain the SPT N field value. Soil samples were taken and visually classified at the site based on the USCS system. All samples were stored in zip-loc plastic bags and shipped to our laboratory for further tests. Six monitoring wells were installed during our field exploration, one in each boring. The monitoring wells were installed with 2-inch PVC pipe and slotted PVC pipe as well screen. The screen elevations and depths were decided by our field representative based on the soil and groundwater conditions encountered. One flush mounted monument casing was used for each well and the disturbed street surface was paved with concrete. Groundwater levels were measured in the wells several days after the well installation. The logs of subsurface exploration are included on Plates A2 to A7 in this appendix with explanation of the soil classification and penetration test on Plate Al. Geo Group Northwest, Inc. SOIL CLASSIFICATION AND PENETRATION TEST UNIFIED SOIL CLASSIFICATION SYSTEM USCS GROUP LABORATORY MAJOR DIVISION CLEAN GW GRAVELS GRAVHS GP (t T LE OR NO FlNES) (More Than Half COARSE Coarse Grains Larger GRAINED Than No. 4Sieve) DIRTY GM SOILS GRAVELS GC MITH SOME FINEST More Than Half by Weight CLEAN SW Larger Than No. SANDS SANDS 200 Sieve (L11TLEOR No SP (More Than Hal Coarse Grains Smaller Than No. 4 Sieve) SM DIRTY SANDS SC (wTrH SOVE FV E% Liquid Lima ML SILTS ` 50 FINE- (Below A-Lmon GRAINED Plasticity Chart, Liquid lima MH SOILS Negligible Organic) > 50% Liquid Lima CL CLAYS < 30% Liquid Limit j More Than Hall (Above A4jne on ' by Weight Placlicily Chart, CH Smaller Than Negligible Organic) > 50% ORGANIC Liquid Lima OIL No. 200 Sieve SILTS & CLAYS A e on i Liquid Lima C Pisc-ticity art) I > 50% OH HIGHLY ORGANIC SOILS i Pt TYPICAL DESCRIPTION I CLASSIFICATION CRITERIA WELL GRADED GRAVELS, GRAVEL -SAND MIXTURE, DETERMINE Cu = P60 / Di 0) greater then 4 LITTLE OR NO FINES SAGES Cc - (D30 ' D30 / Di 0 / D60) between 1 and 3 OF POORLY GRADED GRAVELS, AND GRAVEL -SAND GRAVEL AND MIXTURES LITTLE OR NO FINES SAND FROM NOT MEETING ABOVE REQUIREMENTS GRAIN SIZE DISTRIBUTION i ATTETiBERG LIMITS BELOW •A' LINE SILTY GRAVELS, GRAVELSAND.SILT MIXTURES CURVE, CONTENT or P.I. LESS THAN 4 OF FINES CLAYEY GRAVELS, GRA1lELS(TU AND CLAY MORES COARSE ARE 1 ATTERBEAG UNITS ABOvE'A' LINE ARE SOILS or P.I. MORE THAN 7 CLASSIFIED AS WELL GRADED SANDS, GRAVELLY SANDS, UTTLE OR FOLLOWINGS: Cu = (D60 / DI 0) greater than 6 NO FINES Cc = (D30 • D30 / D10 / D60) between 1 and 3 POORLY GRADED SANDS. GRAVELLY SANDS, LITTLE < 5% Fine Grained: NOT MEETING ABOVE REQUIREMENTS OR NO FINES GW, GP. SW, SP; I > 12% Fine Grained. I I ATTERBERG LIMITS BELOW 'N LINE SILTY SANDS, SAND -SILT MD(TURES GM, GC, SM. SC; j CONTEXT with P.I. LESS THAN 4 OF FINES 5 to 12% Fine Grained: IX r ATTEABEAG LIMITS ABOVE'A' LINE CLAYEY SANDS, SANDCLAY MDaURES use dual symbols. , t2% with P.I. MORET7 4 N 1 INORGANIC SILTS AND VERY FINE SANDS, ROCK FLOUR SILTY SANDS OF SLIGHT PLASTICTY INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS. FINE SANDY OR SILTY SOIL s INORGANIC CLAYS OF LOW PLASTICITY, GRAVELLY. 40 SANDY. OR SILTY CLAYS. CLEAN CLAYS = 30 - INORGANIC CLAYS OF HIGH PLASTICITY, FAT CLAYS j — q 20 ORGANIC SILTS AND ORGANIC SILTY CLAYS OF s LOW PLAsnarY 10 - ORGANIC CLAYS OF HIGH PLASTICITY MINES 00061offilms 1021020000 1201100230 0 10 20 30 40 50 60 70 80 90 100 PEAT AND OTHER HIGHLY ORGANIC SOILS LIQUID LIMIT (96) SOIL PARTICLE SIZE GENERAL GUIDANCE OF SOIL ENGINEERING PROPERTIES U.S. STANDARD SIEVE _ _ FROM STANDARD PENETRATION TEST (SPT) Passing Retained SANDY SOILS SILTY & CLAYEY SOILS FRACTION Size i Size Blow Relativen BlowF Blow Unconfined — -- Sieve Sieve —._. (mm i -(mm1--. Counts Density { Angle Description Counts Strength Description SILT / CLAY #200 1 0.075 N °h 0, degree N Su, tsf - ----- -- SAND j � 0-4 0 -15 j Very Loose < 2 < 0.25 Very soft FINE j #40 i 0.425 #200 I 0.075 4 - 10 15 - 35 I 26 - 30 Loose 2-4 0.25 - 0.50 Soft I MEDIUM ! # 10 0 #40 0.425 10 - 30 35 - 65 ' 28 - 35 Medium Loose 4-8 0.50 - 1.00 Medium Soft COURSE ! #4 1 4.75 1, # 10 2 30-50 65 - 85 35 - 42 Dense 8 - 15 1 .00 - 2.00 Stiff -------- GRAVEL > 50 85 - 100 j 38 - 46 Very Dense 15 30 2.00 - 4.00 Very Stilt FINE 19 1 #4 i 4.75 > 30 > 4.00 Hard COURSE i76 19 COBBLES I 76 mm to 203 mm Geo Group Northwest, Inc. Geotechnical Engineers, Geologists & Environmental Scientists 13240 NE 20th Street, Suite 12 Bellevue, WA 98005 Phone (206) 649-8757 Fax (206) 649-8758 PLATE A-1 BOULDERS > 203 mm --- ROCK FRAGMENTS > 76 mm ROCK I >0.76 cubic meter in volume Or - M- I Ur v BOREHOLE NO. 1 SURFACE ELEVATION 29.5(f) feet SAMPLES AND TESTS m SPT-N, blows/ft t; " LL = U a U SOIL DESCRIPTION z ae ♦ Water % io 7 `° S o` LU U' Z y 3 20 40 O a - b Asphalt pavement and crushed rock base __ ........................... ....... .__.. ............. _ ... ' _........................ - !-^ ti a.XMt MI Mottled tan and gray, SILT with some clay, medium stiff to soft, very moist. 1 5 44.2 • ♦ r we Bm.k Pia 5 2 3 3 35-4 - ........... .._------_._ ............................. . - ............. ................-- .------...............>._- 37.0 ------ ----_ - ...-,.....�._..,--..-:_ asps ML Dark gray, CLAYEY SILT, interbedded with olive gray fine to medium grained sand and gray silt, medium stiff to stiff, very 4 I 10 29.6 ` 10 moist to wet. 5 5 21.6 cvv 10 3' ' /1M3 '.....i----------------------- 6 5 37.8 0 15 7 4 35.4 .i 8 I 10 36.7 20 --------- --- .._............................._..._.....-......- - ...... - - ....................... ; 9 2 160.6 ; Pt Mottled dark brown, light brown, PEAT with wood chips 10 7 25 s+io. Sam , GW Gray, SANDY GRAVEL, dense, wet. 11 38 7.1 e.2o - ♦ -- �. z'PVc sc� , . ' 12 I 40 30 ' 13 25 3.4-------------- I (Some soil heave into auger) 14 I 17 35 Boring ended at 32.5 feet, sampled to 34 feet. i 40 LEGEND: = 2" O.D. Split -Spoon Sample IT 3" O.D. Shelby -Tube Sample 3" O.D. California -Sampler Sample — SOIL TEST BORING LOG LOGGED BY DH ®1 Group Northwest, Inc. METRO CEDAR RIVER TRUNK BORING DATE 7/8/93 RELOCATION PHASE -II JOB NO G-0346 Geotechnicaf Engineers, Geologists, b Environmental Scientists RENTON, WASHINGTON PLATE A2 )AN1ELtFlELDIB0RING{L0G34681.AS a'N BOREHOLE NO. l SURFACE ELEVATION 31(t)feet SAMPLES AND TESTS . SPT-N, blows/ft d v LL U H a U SOIL DESCRIPTION y Z 3e ♦ Water % CL 0 ' Z ~ y R 3 20 40 'a - 4" Asphalt pavement gravel base _.._._......"-. ........... :.....:.....:..... hionumerd � CL Mottled tan and gray, SILTY CLAY, soft, moist. I 1 3 41.6 rwc 5 .................... ML ............. . .........................---------................---......-------------..........------ Mottled reddish brown and gray, CLAYEY SILT, soft, moist. _............._-.-... ------- ...............:.....:..._;_-..;.....;.....; s pip. SM Dark gray, SILTY FINE SAND, loose, moist to wet. to 3 I 6 29.5 ■ L .....:.....:.....:.....:.....:.....: GW - 10 ML 4 I 4 30.1 I I •` /78/83 Interbedded with clayey silt 5 I 7 31.3 ■ r 15 6 3 28.5 .............. ............. ..... .......... ................................................. ...... - ---- ...................-. 25.1 -------- Pt Mottled dark brown, light brown, PEAT with wood chips,wet. --7--- -I- 7 ......... .... ■. . 20 ....._ .............. SC .. .............• •• •-• . • • •----•-................. -.............---.................................. Dark gray, CLAYEY FINE SAND with scattered black peat. .. ........... 46.4 _..._....:.._.:..... .......... �`4s;a ............... - _................-----------------........ ............. .------------------- ............. _.......... ...-_.......... ...8....L -..3.1_. ... a-rzo .......... GW Dark gray, SANDY SILTY GRAVEL, dense, wet. i rwc s«aa,, 9 I 47 15.4 r - ...............soy 25 Nab- ]0 T 47 10.4 _ Boring ended at 25 feet, sampled to 26.5 feet. 1 30 1 35 40 LEGEND: = 2" O.D. Split -Spoon Sample 3" O.D. Shelby -Tube Sample TT3" O.D. California -Sampler Sample SOIL TEST BORING LOG LOGGED BY DH Group Northwest, Inc. METRO CEDAR RIVER TRUNK BORING DATE 7/8/93 Geotechnical Engineers, Geologists, b RELOCATION PHASE -II JOB NO G-0346 Environmental Scientists RENTON, WASHINGTON PLATE A3 DANIEL lF1ELDIBORINGtL 06 34682 XLS VIM 11 I I BOREHOLE NO. 3 SURFACE ELEVATION 33.5(f) feet LL U SAMPLES AND TESTS N SPT-N, blows/ft `m a U SOIL DESCRIPTION z se ♦ Water % is 3 °/ ar r c (� = z H 3 o 0 y 20 40 (3 'g - 4" Asphalt pavement and gravel base ...... .......... ...... --------- ......... -- ---------------------- _ .. t..... .. nush ML Light brown, SILT with trace of sand and clay, medium stiff, damp. 1 5 16.1 .....:.....:..... ■ ♦€ r Pvc ear Pipe 5 Bentorite 2 6 31.9 PS .... .......... SM .................. . ...... .. ........ Tan, SILTY FINE SAND, loose, damp . 3 T 5 16.7 ■ 10 ....... i f ......... ..................................... ML ----------------------- - .........-................. ..... ............... ...._..--------.........- Gray, SILT little fine sand, scattered dark peat and brown wood 4 3 49.2 _ chips, soft, moist. . ....... ............. ... .... ............ _ ............. ML Dark gray, CLAYEY SILT interbedded with fine silty sand, soft, 5 T 3 37.0 ♦! 15 to very moist. Gw SM 6 3 28.8 . ee3 ` P --A .... ,.. .' ....... ........ ...................................... .----------_-.. _... 2 PVC Screen � SW Olive gray, GRAVELLY SAND with little silt, medium 7 T 24 14.4 ♦ ; ■ 20 dense to very dense, wet. Sift sar,a 8 50 11.3 0 1 o szo ..- - ..----- 9 T 55 15.1 ♦: ■ 25 10 T 24 Boring ended at 25 feet, sampled to 26.5 feet. 1 30 1 35 40 LEGEND: = 2" O.D. Split -Spoon Sample 3" O.D. Shelby -Tube Sample 3" O.D. California -Sampler Sample SOIL TEST BORING LOG LOGGED BY DH ®1 Group Northwest, Inc. METRO CEDAR RIVER TRUNK BORING DATE 7/8/93 Geotechnical Engineers, Geologists, & RELOCATION PHASE -II JOB NO G-0346 Environmental Scientists RENTON, WASHINGTON PLATE WYICLirILLU10VKM�(iLL W.NIDo.1..lLJ 7//AN. I m -m z 2 BOREHOLE NO. 4 SURFACE ELEVATION 34.5(f) feet SAMPLES AND TESTS w SPT-N, blows/ft LL U a y SOIL DESCRIPTION z ae ♦ Water % a w G 9 0 M E = 5,� I— a y d is r E 0 o� z 3 20 40 O a ....... 6" Asphalt pavement and Gravel Base :................. ..... Fiu.n ML Mottled gray and brown, FINE SANDY SILT, meditun stiff, moist ...........:.....:.....-- 1 7 23.3 r PVC ■j A War* Pip. s_ .............. .............. .....---- ................ ............................................... .---- -.......-...._._........__.....-.._.................. .... ....- --------- .. _. GW Light brown to gray, SANDY GRAVEL with trace of silt, medium 2 15 2.9 ,... i-04----- i----i.....i dense, damp. Bwl=e ..-.....-.i. _...I_.......-. gtiP. (trace of brick chips at 8 feeet) 3 I 31 3.1 :A r 10 4 37 --------------- ---- --- ------ I - - ------- _....... SP Light brown to gray, SILTY GRAVELLY SAND, medium dense, 5 13 7.4 I4■ 15 damp.GW 6 11 15.27/1 01 4r e e3 _........... __ ................_....................._............._._._..._................................... 7 ...1._.. 9 -- r Pvc Sue, 20 ML Dark gray, SILT with little fine sand and trace of PEAT. ..... ....... ................... .... ......... .................-._......._..............._.............._...._...------------------_ 8 34-- 147 ca«ido ..---:.�.:.....: �.:.... SING Sind GW Gray, SILTY SANDY GRAVEL, dense, wet. 9 10-J20 9 30 15.4 ♦! ■ zs SA - 10 29 Boring ended at 25 feet, sampled to 26.5 feet. 30 35 40 LEGEND: Z 2" O.D. Split -Spoon Sample -71 3" O.D- Shelby -Tube Sample 3" O.D. California -Sampler Sample — SOIL TEST BORING LOG LOGGED BY DH Group Northwest, Inc. METRO CEDAR RIVER TRUNK BORING DATE 7/8/93 JOB NO G-0346 RELOCATION PHASE-11 Geotechnical Engineers, Geologists, d PLATE A 5 Environmental Scientists RENTON, WASHINGTON DAMEL%F1ELD%80R/NGLL0G546B5 AS 7119/9 4 BOREHOLE NO. 5 SURFACE ELEVATION 34.5(f) feet SAMPLES AND TESTS 0 SPT-N, blows/ft _ =a V SOIL DESCRIPTION ♦ Water % Z e C = °V (�7 Z N o 20 40 �7 n . 6" Asphalt pavement and gravel base ......... ..........---...........----. s ;.....:.....:..........Fkh ti MI, Yellowish brown, SANDY SILT, soft to medium stiff, damp ..... .... ........ ......_.... __ _.. - - 1.... I .. 4 28:7........ ■ : € vc A €.....; � Pipe 5 SM Light brown SILTY SAND, very loose, damp. 2 4 19.7 B.rtaite SW Light brown to gray, GRAVELLY SAND with trace of silt, loose, 3 I 7 6.2 ■ 10 moist. ........................................ GW ........._..........._. --..........._..............._.-............_ ................... Light brown to gray, SANDY GRAVEL with trace of silt, loose, ----- - 4T . ......... 6 .. . �.... moist. I :...........:... r avc ■ sue, 5 6 15 changes to dense, wet. 6 36 - ! Gvr , ..........:.....:. , f ®15 7 I 7 49 - 20 ............................ ....... .......... .......... ........ ... _.. ; Colorado Si fa Sam • ' SM Dark gray, SILTY FINE SAND interbedded with silty clay and silt, 8 T 34 27.8 s,o ♦ a dense, wet. . ------------ `r 9 I 23 26.3 - 25 Sdi changes to loose. 10 7 30.3 ■ ......�............... Boring ended at 25 feet, sampled to 26.5 feet. 30 35 40 I I LEGEND: I 2" O.D. Split -Spoon Sample 7 3" O.D. Shelby -Tube Sample TI3" O.D. California -Sampler Sample — SOIL TEST BORING LOG LOGGED BY DH Group Northwest, Inc. METRO CEDAR RIVER TRUNK BORING DATE 7/8/93 JOB NO G-0346 RELOCATION PHASE -II Geotechnical Engineers, Geologists, d PLATE A 6 _ Environmental Scientists RENTON, WASHINGTON 7ANAEL WELD180RING1L0G34665. XLS /q - BOREHOLE NO. 6 SURFACE ELEVATION 36.5(f) feet SAMPLES AND TESTS ■ SPT-N, blows/ft = a U SOIL DESCRIPTION .2 Z e ♦ Water % - a _ .- c o ' Z � 3 S ° 20 40 O n. 6" Asphalt pavement and 3 to 5" Crushed Rock Base ------ -.... -.... .... -.... ___... .,,�. hq Yellowish brown, SILT, medium stiff to stiff, damp rwc 1 I 8 29.3 :-...... A, Bhb* Pipe _....... _...... ..-._..... - _... ............ SP Mottled yellowish brown FINE TO MEDIUM SAND with 2 18 18.1 gray, trace of gravel and silt„ medium dense, damp. s.....:.....:......... . ome . _....... __....._ _.. .............................. - ...... ps __ ... _._ GW Light brown, SAND GRAVEL with trace of silt, dense to very 3 I 34 3.5 ♦ ' • 10 dense, damp. 4 65 changes to wet. _. . .. 5 44 7.3 .. 12.7 15 6 19 __._ ............_....._.. .......__-----------------------•---........ .......-- --- . ...-----....... -- . ......_.._ - _.........-...........i.....l... r we s NIL Dark gray, FINE SANDY SILT, interbedded with FINE to MEDIUM 7 I 13 20.9 20 to SAND, stiff / medium dense, moist. Colorado s4" sww SM 8 15 28.1 = - 9 I 12 37.0 .....;- 25 trace of wood chips. 10 9 27.5 .....- �........... Boring ended at 25 feet, sampled to 26.5 feet. 30 _ 35 i - 40 LEGEND: = 2" O.D. Split -Spoon Sample 3" O.D. Shelby -Tube Sample 3" O.D. California -Sampler Sample SOIL TEST BORING LOG LOGGED BY DH ®1 Group Northwest, Inc. METRO CEDAR RIVER TRUNK BORING DATE 7/8/93 Geotechnical Engineers, Geologists, a RELOCATION PHASE-11 JOB NO G-0346 Environmental Scientists RENTON, WASHINGTON PLATE A7 0ANIEL TIELOIBORINGLLOG34686.XLS I L." PROJECT: HNTB!METRO SEWER RECORD OF BOREHOLE #7 SHEET 1 OF 1 RELOCATION,/WA DATUM: MSL PROJECT NUMBER: 893-1108.003 BORING LOCATION: Factory Ave N. @ N. Brooks St. BORING DATE: 7/22J91 C SOIL PROFILE SAMPLES PENETRATION RESISTANCE BLOWS7FT / PIEZOMETER W LL H DESCRIPTION S2 < p O ELEV 0 10 20 30 40 GRAPHIC BLOWS/6IN. ¢ N <F WATER CON W NZPERCENT WATER 140 C. 1 Ammer 30 lrrn drop ¢ 0 W10 20 30 4p LEVEL 50 DEPTH 0 Fk h tall 3' Asphah pa,ener NA 0. A- S'6' mnus crushed rocx 0.6 c— Very bole. yelbwish broom (10YR 5,14). foe to Sot s• medwm SAND. Irmo to some sit, trace gravel to uhy line to mocl SAND, trace prave: tra: e - oryania ISM) I t SS 2 2 2 4 1.S" 5 ? aC PV N _ 5 16. 2 SS 1.1112' 1 121.5� 14arnn 4 Gip 3 SS 1-4-6 -- 10 0.7/1.5 65 Loose to corrpacl, olive pray (5Y 3.2) 10 dark - yellowish brown (10YR 42), fine to coarse 10 SAND and fine to coarse GRAVEL, trace sill (Gxr) GW a SS a-E-11 17 0.7i1.5 I 5 SS 13-7513 15 < v I . 6 1.0.t_5 e612 Sans 6 SS 13-5-3 L o:ne I cc riper,, rredum da rK pray (4N4), ITC 7 SS 1-24 ' �e SA!.'D, some silt trace line gravel ISM) Sp 6 1.5'1.5 Gw tLa it } ' 2:, aimed — PVC E SS 3-5-5 1C 1.51.5 14 LS'1.5 9 SS 2-59 c+: borehole lermnaleo a1 24 Iasi, 722191 24.0 25 G'o�nd..aiw enoounlered 17.6 1"! bebw E'c�nC lave'. 3: i I DRILL RIG: Moose B-61 LOGGED: S W+qh; DRILLING CONTRACTOR: EDi Q Golder Associates CHECKED: K. Brown DRILLER: S. McCa DATE: 621/97 PLATE A 8 PLATE A 9 W i lim �-.m • .k F �I •. ...1..._ ;���y... o