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SITEJ!!E(IIU,tATIQ!'I SITE AREA: 209.72D SF SITE IMPERVIOUS SURFACE ,EXISTINGI, 209 088 SF (PROPOSED): 179.109 SF , . . iii" __ (1,---- .i:;l:Iil ~ LOT COVERAGE 1BUILDING1, I 6.644 SF 17.9%) (SERVICE BUILDING), 3.57B SF 11.7~1 TOT Al GROSS LOT COVERAGE. 20.222 SF (9.6%1 PARKING SPACES (RE0'01, 33 MIN (PR0\1"01, 98 STALLS 14 HC REQ'D. 4 HC PROVO) PA~R--AYE. _N.i, PARKING LANDSCAPE (R!;a'Dl, 9B • 25 SF PER ST ALL~ 2.450 ~-------------- (PROV"D), J.Slt.SF __ 'cc __ _ ' ---= -- = ------- A ~ SITE PLAN. REVISIONS -------~S---'----'rf.___..E...__.__Pl __ --'-'-'P..~J<J"--",·~ru:r ,r; $ -1-1 .-.. ,, - A1.01 ""'''~ "" - The Tranwo Group MEMORANDUM Date: July 20, 2007 TG: 07193.00 To: Stewart Shusterman, Renton School District From: Bart Przybyl, P.E., The Transpo Group, Inc. Subject: Renton School District Transportation Center -Traffic Impact Analysis Per your request, we have performed a traffic impact analysis for the proposed changes in land use of the Renton School District Transportation Center located in the City of Renton. Specifically, the changes include re-location of some of the school disttict's departments off-site and re-location of the site access points. As a result, the analysis focuses on comparing the trip generation of the existing and proposed uses, evaluating the site access points, and determining the projects impact on adjacent intersections. This scope is based on discussions with City of Renton staff. Our analysis and findings are summarized below. Proiect Descrintion . . The subject site occupies the city block bounded by Park Avenue North, Garden Avenue North, North 4th Street, and North 5th Street. The site has access to each of the four roadways via a single, full-movement access point, for a total of four access driveways. The project includes changes to the Renton School District 'l'ransportation Center to re-locate the Capital Projects and Maintenance and Operations departments off-site and increase the amount of parking space available for school buses. Specifically, the building size will be reduced from 22,374 square feet to 15,421 square feet. Passenger car parking will also be reduced from 14 7 parking spaces to 104 parking spaces. The additional spaces will be utilized to increase the school bus parking capacity by 15 spaces from 89 spaces to 104 spaces. Based on this proposed increase in bus storage capacity, the proposed facility wil1 have a maximum capacity to accommodate 94 employees, including 80 drivers and 14 administrative staff/mechanics. Although the amount of passenger car parking is being reduced, it will exceed the maximum 69 parking spaces allowed by the City of Renton for office-related uses. However, the proposed use for the site as a transportation center is not a typical office use where most employees stay on-site. The additional spaces are necessary in order to accommodate personal vehicles left on-site by bus drivers as they are out on their routes. As a result, the proposed parking supply is reasonable given the unique nature of the proposed uses. The access plan will stay relatively the same with some of the access points relocated to be positioned further away from adjacent intersections. In addition, the access driveways along North 4th Street and North 5th Street will be inbound only while the other two access points along Park Avenue North and Garden Avenue North will The Transpo Group Inc. 11730 118th Avenue N.E .. Suite 600 Kirkland, WA 98034-7120 425.821.3665 Fax: 425.825.8434 serve both inbound and outbound vehicles. Finally, the Park Avenue North and North 5th Street access points will only serve the passenger parking areas, while the access points on Garden Avenue North and North 4th Street will serve school buses only. A site plan showing the proposed changes as well as the proposed access plan is shown in Attachment A. Trip Generation Analysis In order to determine the effect of the proposed changes in use on the surrounding roadways, a trip generation analysis was performed to compare the traffic generated by the existing uses to that expected to be generated once the project is complete. Description of Changes in Land Use The existing site houses the Capital Projects, Transportation, and Facilities Maintenance and Operations departments. The Transportation department currently represents 75 bus drivers, 89 school buses, and approximately 13 administrative staff/mechanics, all of which work a single shift. In addition, the Capital Projects and Facilities Maintenance and Operations departments (which will be relocated as part of the project) currently represent a total of 45 employees which work a single shift. Approximately 70 to 80 percent work from 7:00 a.m. to 3:00 p.m. while the remaining 20 to 30 percent working past 3:00 p.m. The relocation of the Capital Projects and Facilities Maintenance and Operations departments will provide the Transportation department additional space to store school buses. As previously mentioned, the capacity for an additional 15 school buses will be provided on-site. Trip Generation Comparison Typically, trip generation for a development is estimated using nationally accepted rates published by the Institute of Transportation Engineers (!TE) in Ttip Generation, Th Edition. However, T tip Generation does not include land use categories or rates that match the existing or the proposed land uses. Therefore, trip generation was estimated based on the information provided by the Renton School District. The trip generation of the existing uses was estimated assuming that all employees arrive during the AM peak hour and 30 percent of employees depart during the PM peak hour. Exiting AM peak hour trips and entering PM peak hour trips were estimated based on the entering/ exiting percentage split for office buildings taken from Trip Generation (LU 710, General Office Building). For school buses, it was assumed that all would leave the site during the AM peak hour (6:30 a.m. to 7:30 a.m.) and 30 percent would return to the site during the PM peak hour (3:30 p.m. to 4:30 p.m.) which is later than the school PM peak hour. Please note that although the school district currently has 89 school buses, only 7 5 can be used at a time due to the number of available school bus drivers. Furthermore, the district only plans to have 64 bus routes next year. As a result, only 64 buses are The Transpo Group Page 2 expected to be utilized with the additional drivers acting as substitutes. However, in order to provide a conservative estimate of trip generation, it was assumed that all 75 bus drivers would be utilized. The results are shown in Table 1. As shown, the existing uses currently generate approximately 747 trips per day. During the AM peak hour, the site generates approximately 228 total trips with 133 entering trips and 95 exiting trips. Since the majority of staff and school buses (about 70 percent) currently leave/return to the facility prior to the PM peak hour, only 73 total trips are estimated during the PM peak hour with 32 entering trips and 41 exiting trips. The trip generation of the proposed uses was estimated using the same assumptions as those for existing uses. The results are also shown in Table 1. As shown, a total of 694 daily trips are expected. During the AM peak hour, the proposed uses are expected to generate approximately 210 total trips with 106 entering trips and 104 exiting trips. During the PM peak hour, a total of 66 trips are expected with 34 entering trips and 32 exiting trips. Table 1. Trip Generation Summary Project Trips1 Daily AM Peak Hour PM Peak Hour Land Use No. Total Total In Out Total In Out Existinq Use Bus Drivers 75 225 85 75 I 0 27 4 23 Buses 75 300 75 0 75 23 23 0 Administrative Staff/ Mechanics 1 3 52 15 13 2 5 I 4 Other Employees (to be relocated) 45 170 53 45 8 18 4 14 Total 747 228 133 95 73 32 41 Proposed Use Bus Drivers 90 270 102 90 12 33 6 27 Buses 90 360 90 0 90 27 27 0 Administrative Staff/ Mechanics 16 64 18 16 2 6 I 5 Total 694 210 106 104 66 34 32 Increase/Decrease in Trip -53 -18 -27 +9 -7 +2 -9 Generation Percent Increase/Decrease in ·7% -8% -20% +9% -10% +6% -22% Trip Generation 1. Trips estimated based on information provided by the client. Comparing the results, the land use changes proposed as part o.f the project will result in an overall decrease in the number of trips generated by the site. Approximately 53 less total trips are expected on a daily basis with 18 less total trips during the AM peak hour and 7 less total trips during the PM peak hour. 'l'his represents a reduction of 7 percent of daily trips, 8 percent of AM peak hour trips, and 10 percent of PM peak hour trips. The Transpo Group Page 3 With-Project Traffic Volumes In order to determine the operations of the site driveways and the intersections of North 4th Street/Park Avenue North and North 5th Street/Park Avenue North, with-project traffic volumes were estimated. Existing Traffic Volumes To obtain existing weekday AM and PM peak hour traffic volumes at the North 4th Street/Park Avenue North and North 5th Street/Park Avenue North intersections, turning movement counts were collected in June 2007. As a result, they include the traffic generated by the existing uses on the site. The resulting volumes are shown in Attachment B. Existing through traffic on Garden Avenue North was assumed to be 25 percent of the through traffic on Park Avenue North. This is based on the comparison of daily traffic volumes on both roadways provided in the Transportation Section of the City of Renton Comprehensive Plan. Project Trip Distribution and Assignment The project trips summarized in Table 1 were distributed and assigned to the site access points and nearby intersections using two different distribution patterns. The first distribution was used to assign employee trips and was based on the existing travel patterns in the area and nearby land uses. Specifically, 36 percent of employees were assumed to be traveling to and from the south, 29 percent to and from the east, 28 percent to and from the west, and the remaining 7 percent to and from the north. The second trip distribution was used to assign school bus trips and was est:itnated based on information provided by the Renton School District and the proposed access plan. As previously mentioned, all outbound trips will utilize the site access on Garden Avenue North and travel north to access northbound Park Avenue North or south to access westbound North 4th Street, southbound Park Avenue North, or eastbound North 3rd Street. Inbound trips will utilize the access points on North 4th Street and Garden Avenue North. The specific trip distribution patterns assumed for the buses are that 33 percent travel to and from the south, 26 percent to and from the west, 24 percent to and from the east, and the remaining 17 percent to and from the north. The resulting project generated traffic volumes are shown in Attachment C. Please note that total trips are shown at driveway locations but only the net difference in trips is shown at external intersections since these locations include traffic generated by the existing uses. The project generated traffic volumes were then added to the existing traffic volumes to yield with-project conditions. The results are shown in Attachment D. 'l.t" 4c,-ec" {),.•~;· "''/.0/·IS _it c-.. 1 ,_ "'I., .,~>.Jo "-"'J./C:.. Ml. _ An operations analysis was conducted for the site access driveways during the AM and PM peak hours to evaluate the levels of service under with-project conditions. The Transpo Group Page 4 - Level of service (LOS) is used to evaluate and quantify operating conditions and traffic congestion at intersections and driveways. LOS values range from A, which is indicative of free-flow traffic conditions, to F, which indicates extreme congestion and long delays. The LOS was based on procedures identified in Highway Capacity Manual (Transportation Research Board, 2000), and was evaluated using the Synchro, version 6.0, software. The levels of service and delays for with-project conditions are summarized in Table 2. The detailed LOS worksheets are attached to the back of this report. Table 2. Weekday AM and PM Peak LOS Summary at Driveways AM Peak Hour PM Peak Hour Driveway Location LOS 1 Delayz WM' LOS Delay WM Park Avenue North/Site Driveway C 15.5 WB B 12.6 WB Garden Avenue North/Site Driveway B I 0.3 EB A 8.8 NBLT North 4th Street/Site Driveway A 0.0 N/A A 0.0 N/A North 5th Street/Site Driveway A 0.0 N/A A 0.0 N/A l. Level of service, based on 2000 Highway Capacity Manual methodology. 2. Worst movement delay. 3. Worst movement (movement or approach experiencing the greatest delay). ,\s shown, all movements at the site access driveways are expected to operate at LOS C or better with worst movement average vehicle delays of 16 seconds or less. In fact, the two inbound-only access points on North 4th Street and North 5th Street are expected to experience no delay. In addition, 95''-perccnrile queue lengths at the driveway exit approaches are not expected to exceed one vehicle. An operations analysis was also conducted for the adjacent intersections along Park ,,I, venue North to evaluate the impact the project might have on these intersections. In order to <lo so, existing conditions were compared to with-project conditions. The results arc summarized in Table 3. Please note that the intersections along Garden Avenue North were not studied <lue to their relatively low traffic volumes. The Transpo Group Page 5 Table 3. Weekday AM and PM Peak LOS Summary at Adjacent Intersections Existing Existing + Project V/C3 or V/Cor Driveway Location LOS' Delay2 WM' LOS Delay WM Weekdar AM Peak Hour Park Avenue North/North 4th Street B 16.7 0.43 B 16.7 0.43 Park Avenue North/North 5th Street B 12.7 EB B 12.9 EB Weekdar PM Peak Hour Park Avenue North/North 4th Street B 1 5.4 0.37 B 1 5.5 0.36 Park Avenue North/North 5th Street C 1 5.4 EB C 1 5.4 EB l. Level of service, based on 2000 Highway Capacity Manual methodology. 2. Average delay in seconds per vehicle. Overall intersection delay is reported for signalized while worst movement delay is reported for two-way Stop controlled Intersections. 3. Volume-to-capacity ratio. 4. Worst movement reported for two-way Stop controlled intersections (movement or approach experiencing the greatest delay). As shown, the proposed project is expected to have a very minimal impact on the adjacent intersections. In fact, average vehicle delay is expected to increase by less than one second per vehicle. c:.,1,i'nc,·r;; dnd Cond11s1ons The following provides a brief summary of the results of the traffic impact analysis for the proposed Renton School District Transportation Center project. • The existing uses on the site currently generate approximately 7 4 7 total daily trips. In addition, 228 total trips are currently generated during the AM peak hour with 133 entering trips and 95 exiting trips. During the PM peak hour, a total of 73 trips was estimated with 32 entering and 41 exiting. • With the proposed changes, the site is expected to generate approximately 694 total daily trips. In addition, 210 total trips are expected during the AM peak hour with 106 entering trips and 104 exiting trips. During the PM peak hour, a total of 66 trips are expected with 34 entering trips and 32 exiting trips. • Comparing the existing and proposed uses, the land use changes proposed as part of the project will result in an overall decrease in the number of trips generated by the site. Approximately 53 less total aips arc expected on a daily basis. In addition, 18 less total aips are expected during the AM peak hour and 7 less total aips are expected during the PM peak hour. This represents a reduction of 7 percent of daily trips, 8 percent of AM peak hour trips, and 10 percent of PM peak hour aips. • ,\11 movements at the site access driveways are expected to operate at LOS C or better with worst movement average vehicle delays of 16 seconds or less. In fact, the two inbound-only access points on North 4th Saeet and North 5th Street are expected to experience no delay. In addition, 95'h -percentile queue lengths at the exit approaches are not expected to exceed one vehicle. The Transpo Group Page 6 • The proposed project is expected to have a very minimal impact on the adjacent intersections along Park Avenue North. In fact, average vehicle delay is expected to increase by less than one second per vehicle. I trust you will find this memo responsive to your request. Do not hesitate to contact me at (425) 821-3665 if you have any questions. Attachments i\1:\(!7\07193 H.SD Tran:sportation Lcnt..:r\wp \071 IJ.1m2.Joc The Transpo Group Page 7 ,- ' I I I \ I I I \ I L \. -, il: S' {\Fi-· N. 5TH STREET N. 4TH STREET ' Attachment A Site Plan ---------------------------------------···-··-· Renton School District Transportation Center M:\07\07193 RSD Transportafon Center\Graphics\Graphic 01 <A> bartp 06/26/0710:51 _;_: 'I ! i • .. The Transpo Group r ..... ···-··· ---··-·-··,.····---···-G) N5THST PARK AVE N z w (128) > <( 602 (0)131315) ~ ~ (4)5) \.414) N 5TH ST (6)8--0101 18)10') (25(0) ..., 1--:z :z 13) 7 15 (31) w w 193 > > <( <( 1595) <f) >-~ ~ ~ ~ w w 0 N4THST ,;: Q PARK AVE N (98) 531 133)~ I \. 23173) -540(860) m0 I ( 245186) 175 1544) Attachment B Existing AM and PM Peak Hour Traffic Volumes Renton School District Transportation Center M:107\07193 RSD Transportation Center\Graphics\Graphic 01 <B::. bartp 06/26/07 11:58 N 6TH ST z N 3RD ST • N NOTTO SCALE The Transpo Group I CD N5THST PARK AVE N 1-2) 0 j ;!I i._ 013) j iio1 -1 11) 0N4THST PARKAVEN 15) -5 l'lj j i._ 0{-8) -014) t ( 0{8) 4 1-17) @ N 5TH STREET SITE DRIVEWAY 1013--013) 13)0") ® SITEDRIVEWAY GARDEN AVE N 10121 __, 115)0) 175)0 t ..., 1(0) N 5TH ST ©N4THST SITE DRIVEWAY i._ s 101 -014) N 6TH ST B N 3RD ST ® SITE DRIVEWAY PARK AVE N ···-·· -------------, 1 {6) '-i.. 3 {1) I ( 29113) I _J ! 097) 2 101 Note: Only net new trips are shown at external intersections while total trips are shown at driveway locations. Attachment C Project-Generated AM and PM Peak Hour Traffic Volumes Renton School District Transportation Center M:107\07193 RSD Transportation Center\Graphics\Graphic 01 <C> bartp 07111/07 14:01 • N NOTTO SCALE The Transpo Gmup ' ------------CD N5THST PARK AVE N 11261 602 10113 j 4161 _, '- (4)5) \.417) (6)8--0101 10110, (25101 -, t ,,.. (3) 7 17 (31) 192 1596) N 5TH ST 0 N4THST PARK AVE N z w (103) > 526 <! (36Jj j UJ ~ ~ \. 23165) w s: -640(864) 17)~ t ( 2451941 179 (5271 0 N 5TH STREET SITEDRIVEWAY (43129--29171 1310 I >----------------------------- ® SITE DRIVEWAY GARDEN AVE N (33) 156 10131 (1510) (75)0 I 1i0 t 50 1153) © N4THST SITE DRIVEWAY \. 510) -OOB (1,023) N 6TH ST N 3RD ST ® SITE DRIVEWAY PARK AVE N (131) 622 1~1 \.3(1) ( 29(131 t ;;,7) 200 (6171 '--------------'-------------'----------------------- Attachment D With-Project AM and PM Peak Hour Traffic Volumes Renton School District Transportation Center M:\07\07193 RSD Transportation Center\Graphics\Graphic 01 <D> bartp 07/11/07 14:01 B • N NOTTO SCALE The Transpo Group - Queues 3 : N orth 4th Street & Park Av enue North -'-4\ t ! ~ I! WBT"'"'WBR NBL . NBT SBT SBR Lane Configura tions .ftt .,, .ft t+ 'I' Volume (vph) 860 73 7 537 98 33 Lane Group Flow (vph ) 1040 80 0 598 108 36 Tum Type Perm Penm Free Prolec ted Phases 8 2 6 Permitted Phases 8 2 Free Det ector Phases 8 8 2 2 6 Minimum lnilial (s) 4 .0 4.0 4 .0 4 .0 4 .0 Minimum Split (s ) 20.0 20.0 20 .0 20 .0 20.0 Total Split (S) 45.0 45.0 45.0 45.0 45.0 0.0 Total Split (%) 50.0% 50.0% 50.0% 50.0% 50.0% 0 .0 % Yellow Time (s) 3 .5 3.5 3 .5 3 .5 3.5 All-Red Time (s ) 0 .5 0.5 0 .5 0 .5 0 .5 Lead/Lag Lea d-Lag Optimize? Reca ll Mode C -Max C -Max Max Max Ma x vie Ratio 0 .46 0 .11 0 40 007 0.02 Cont rol Delay 17.8 3.9 17.3 14.0 0.0 Queue Delay 0.0 0.0 0 .0 0 .0 0.0 Total Delay 17.8 3.9 17.3 14.0 0.0 Queue Lenglh 50th (ft) 144 0 11 4 17 0 Queue Length 95th (ft) 180 24 156 32 0 Internal Link Dist (ft} 812 252 580 Tum Bay Length (ft ) Base Capacity (vph) 2239 744 1507 148 1 1455 Starvation Cap Reduct n 0 0 0 0 0 Spill back Cap Reductn 0 0 0 0 0 Storage Cap Reductn 0 0 0 0 0 Reduced vie R atio 0.46 0.1 1 0.40 0.07 0.02 Cycle Length : 90 Actuated Cycle Length: 90 Offset: 43 (48%), Refere nc ed l o phase 8 :WBTL, Start of Gre en Natu ral Cycle: 40 Contro l Type : Actu aled-Coordinated 3: North 4th Streel & Park Av enue North §::. M :\07\07193 R SD Transportation Cenler\Synchro \E x ,sting A M Peak H our .sy7 The T ranspo Group Existing AM Pe ak Hour 6/25/2007 ! I I Sy nchro 6 Report HCM Signalized Intersec tion Capacity Analysi s 3: North 4th Street & Park Avenue N orth .,> -... f -'-4\ Mowmam. :EBl EST EBR---WS[ ... WBT WBR · NBl Lane Configurations .ftt 'I' Ideal Flow (vphpl) 1900 1900 1900 1900 1900 1900 1900 Total Lost ti me ( s ) 4.0 4 .0 Lane Util. Factor 0.91 1.00 Frt 1.00 0.85 Flt Protected 1.00 1.00 Said. Flow (prot) 49 18 1538 Flt Permitted 1.00 1.00 Satd . Flow (~rm) 49 18 1538 Volume (vph) 0 0 0 86 860 73 7 Peak-hour fa c lor. PHF 0.91 0 .91 0.9 1 0 .91 0 .91 0.91 0 .91 Adj . Flow(vph) 0 0 0 95 945 80 8 RTOR R eduction (v ph ) 0 0 0 0 0 44 0 Lane Group Flow (vph) 0 0 0 0 1040 36 0 Hea'.!'.}'. Vehicles (%) 0% 0% 0% 5% 5% 5% 4 % Turn Type Penm Penm Penm Protected Phases 8 Permitted Phases 8 8 2 Act uated Green. G (s) 41 .0 4 1.0 Effective Green. g (s) 41 .0 4 1.0 Act uated g/C Ratio 0.4 6 0.46 Clearance Time (s) 4.0 4.0 Veh icle Extension (s) 3.0 3.0 Lane Grp Cap (vph) 2240 701 vis Rati o Prot vis Ralio Perm 0.21 0.02 vie Ratio 0 .46 0.05 Unifonm Delay, d1 16.9 13.7 Progression Factor 1.00 1.00 Incremental D elay , d2 0.7 0 .1 Delay (s) 17.6 13 .8 Level of Service B B Approach Delay (s) 0 .0 17.3 Approach LOS A B lntersectioifSumma!:l HCM Average Control Delay 16.7 HCM Level of Service HC M Volume to C apacity rati o 0.43 Actuated Cycle Length (s) 90.0 Su m of lost time (s) Inte rs ection Capacity U tilization 43.4% ICU Level of Service Analy sis Period (min) 15 C Criti cal Lane Group M :107\071 93 RSD Transportation Cent erlSynchro \Existing AM Peak H our .sy7 The Transpo Group Existing AM Peak Hour 6/2512007 t I' '-. ! ~ NBT,...NBR SBl SBT SB .ft t+ f' 1900 1900 1900 1900 1900 4.0 4.0 4 .0 0.95 0.95 1.00 1.00 1.00 0 .85 1.00 1.00 1.00 -3469 3252 1455 0.95 1.00 1.00 3306 3252 1455 537 0 0 98 33 0.9 1 0.91 0 .91 0.91 0.9 1 590 0 0 108 36 0 0 0 0 0 598 0 0 108 36 4% 4% 1 1 % 11 % 11 % Free 2 6 Free 41 .0 41 .0 90.0 41 .0 41.0 90.0 0.46 0.46 1.00 4.0 4.0 3.0 3.0 1506 -~ 1481 1455 0.03 c0.18 0 .02 0.40 0.07 0 .02 16.3 13.8 0.0 1.00 1.00 1.00 0.8 0.1 0 .0 17.1 13.9 0 .0 B B A 17.1 10.4 B B ! B 8 .0 A Syn ch ro 6 R eport HCM Unsignalized Intersection Capacity Analysis Existing AM Peak H our 6 : North 5 th Street & Park Avenue North 6/2512007 ,,> -" f -'-~ t ~ '. ! .-' Movemenl EBI: EBT-EBR -WB C.-WBr-WBR -NBL NB-r-NBR -see . SBISBR Lane Configurations 4> 11 f+ Sign Control Stop Stop Grade 0% 0% Volume (vehlh) 4 6 8 0 0 4 3 Peak Hour Factor 0.85 0.85 0.85 085 085 0.85 0.85 Hourly flow rate (vph) 5 7 9 0 0 5 4 Pedestrians Lane Width (fl) Walking Speed (ft/s) Percent Blockage Right tum Hare (veh) Median type None None M edian storage veh) Upstream signal (fl) pX. platoon unblocked 0.90 0 .90 0 .90 0.90 0.90 vC, conflicting volume 526 908 75 828 890 368 151 vC 1, stage 1 conf vol vC2, stage 2 conf vol vCu. unblocked vol 371 793 75 704 773 196 151 IC. single (s) 7.5 6.5 6.9 7.6 6.6 7.0 4 .2 tC. 2 stage (s) IF (s) 3.5 4.0 3 .3 3.6 4 .1 3.4 2 .2 pO queue free % 99 98 99 100 100 99 100 cM capacity (vehlh) 504 289 977 274 285 721 1421 Olrection;,[ane.#.--EB 1 WB 1 wa ·z NB1 NB2 SB ,Slf Volume Total 21 0 5 354 386 82 75 Volume Left 5 0 0 4 0 7 0 Volume Right 9 0 5 0 36 0 0 cSH 488 1700 721 14 2 1 1700 836 1700 Volume to Capacity 0 .04 0.00 0.01 0.00 0.23 0.01 0.04 Queue Length 95th (ft ) 3 o o o o 1 0 Control Delay (s) 12.7 0.0 10.0 0.1 0.0 0.9 0.0 Lane LOS B A B A A Approach Delay (s) 12.7 10.0 0.0 0.5 Approach LOS B B nter&ection Summ!!Q'. Average Delay 0.5 Intersection Capacity Uti lization 30.7% ICU Level of Service Analysis Period (m,n ) 15 M:107\07 193 RSD Transportation Center\Synchro\Existing AM Peak Hour.sy7 The Transpo Group 4f+ 4f+ Free Free 0% 0% 595 3 1 6 128 0 0 .85 0.85 0 .85 0.85 0.85 700 36 7 151 0 660 0.90 736 603 4.3 2.3 99 836 A Synchro 6 Report Queues 3 : North 4th Str eet & Par k Avenue N orth -'-~ t + .,' CaiieGI0!/1!. · WBi WBR -N8t NBT"'""SBi-sBR Lane Configurations ,Ht r' .ft tt r Volume (vph) 640 23 19 175 531 9 1 Lane Group Flow (vph) 903 23 0 198 542 93 Tum Type Perm Perm Free Protected Phases 8 2 6 Permitted Phases 8 2 Free Detect or Phases 8 8 2 2 6 Minimum Initial (s) 4 .0 4.0 4.0 4.0 4.0 Minimum Split (s) 20.0 20.0 20.0 20 .0 20.0 Total Split (s) 45.0 45.0 45.0 45.0 45.0 0 .0 Total Split (%) 50.0% 50 .0% 50 .0% 50.0% 50.0% 0.0% Yellow Time (s) 3.5 3.5 3.5 3 .5 3.5 All-Red Time (s) 0.5 0 .5 0.5 0.5 0.5 Lead/Lag Lead-Lag Optimize? Recall Mode C-Max C-Max Max M ax Max vie Ratio 0.39 0 .03 0 .15 0 .34 0 .06 Control Delay 16.9 5.8 14.7 16.5 0 .1 Queue Delay 0.0 0.0 0.0 0.0 0 .0 Total Delay 16.9 5.8 14.7 16.5 0 .1 Queue Length 50th (ft) 120 0 33 100 0 Queue Length 95th (ft ) 153 13 54 138 0 Internal Link Di st (ft) 8 12 252 580 Turn Bay Length (ft) Base Capacity ( vph ) 2307 741 1338 1597 1568 Starvation Cap Reductn 0 0 0 0 0 Spillback Cap R educln 0 0 0 0 0 Storage Cap Reductn 0 0 0 0 0 Reduced vie Ratio 039 0.03 0.15 0.34 0.06 Cycle Length : 90 Actuated Cycle Length: 90 Offset: 43 (48%). Referenced to phase 8 :WBTL, Start of Green Natural Cycle: 40 Contro l Type : Actuated-Coordinated Spli ts and Phases: 3 : North 4th Street & Park Avenue North [: I~ .. 4 : =,;, : 45, --· ": M:107\07193 RSD Transportation Center\Synchro\Existing PM Peak Hour.sy7 The Transpo Group Existing PM Peak Hour 6/25/2007 I I I Sync hro 6 Report HCM Signalized I n tersection Capacity Analys is 3 : North 4th Street & Park Avenue N o rth ..> -... (' -'-~ f!!ovemant EBI.:· EST EBR WBL_.WBT WBR -NBt: Lane Configuralions .ftt r Ideal Flow (vphpl) 1900 1900 1900 1900 1900 1900 1900 Total Lost lime ( s) 4.0 4.0 Lane Util. Factor 0.91 1.00 Frt 1.00 0.85 Flt Protected 0.99 1.00 Said. Flow (prot) 5066 1599 Flt Penmitted 0 .99 1.00 Sai d . F low (eerm) 5066 1599 Volume (vph) 0 0 0 245 640 23 19 Peak-hour factor. PHF 0.98 0 .98 0 .98 0.98 0 .98 0.98 0.98 Adj. Flow (vph) 0 0 0 250 653 23 19 RTOR Reduction (vph) 0 0 0 0 0 13 0 Lane Group Flow (vph) 0 0 0 0 903 10 0 Heavl Vehicles (%) 0% 0% 0% 1% 1% 1% 10% Tum Type Perm Penn Perm Protected Phases 8 Permitted Phases 8 8 2 Actuated Green, G (s) 41 .0 41 .0 Effective Green, g (s) 4 1.0 41.0 Actuated giC Ratio 0 .4 6 0.46 Clearance Time (s) 4.0 4.0 Vehicle Extension (s) 3 .0 3.0 Lane Grp Cap (vph) 2308 728 vis Ratio Prat vis Ratio Perm 0.18 0.01 vie Ratio 0 .39 0.01 Uniform Delay, d1 16.2 13.4 Progression Factor 1.00 1.00 Incremental Delay, d2 0.5 0.0 Delay (s) 16 .7 13.5 Level of Service B B Approach Delay (s) 0.0 16 .7 Approach LOS A B _inteisection' Summ&!Jl HCM Average Control Delay 15.4 HCM Level of Service HCM Volume to Capacit y ratio 0.37 Actuat ed Cycle Length (s) 90.0 Sum of lost time (s) Intersection Capacity Utilization 43.6% ICU Level of Service Analysis Period (min) 15 C Cntical Lane Group M:107\07193 RSD Transportation C enter\Synchro\Existing PM Peak Hour .sy7 The Transpo Group Existing PM Peak Hour 6125/2007 t ~ '. + .,' NBi NBR~SBC se.-se oft tt r 1900 1900 1900 1900 1900 4 .0 4 .0 4.0 0.95 ·-0.95 1.00 1.00 1.00 0 .85 1.00 1.00 1.00 3266 3505 1568 0.89 1.00 1.00 2937 3505 1568 175 0 0 531 91 0.98 0.98 0 .98 0.98 0.98 179 0 0 542 93 0 0 0 0 0 198 0 0 542 93 10% 10% 3% 3% 3% Free 2 6 Free -41 .0 41.0 90.0 41 .0 41 .0 90.0 0.46 0.46 1.00 4.0 --· 4.0 3.0 3.0 1338 1597 1568 . - c0.15 0 .0 7 --0.06 0 .1 5 0 .34 0.06 14.3 15.8 0.0 1.00 1.00 1.00 0 .2 0 .6 0.1 14.5 16.4 0.1 -B B A -14.5 14.0 B B B 8 .0 A Synchro 6 Report HCM Unsignalized Intersect ion Capacity Analysis 6: North 5th S treet & Park Avenue North ..,. -t I'" -~ ~ EBT EBR---wBt: WBT WBR NBt: Lane Configurat ions 4, 'I l> Sign Control Stop Stop Grade 0% 0% Volume (vehlh) 5 8 10 25 0 4 7 Peak Hour Factor 0.95 0.95 0.95 0.95 0 .95 0.95 0.95 Hour1y flow rate (vph) 5 8 11 26 0 4 7 Pedestrians Lane Width (ft) Walking Speed (fVs) Percent Blockage Right tum flare (veh) Median type None None Median storage veh ) Upstream signal (ft) pX. platoon unblocked vC, conflicting volume 767 881 324 564 879 109 647 vC 1, stage 1 conf vol vC2 , stage 2 cont vol vCu , unblocked vol 767 881 324 564 879 109 647 IC, s ingle (s) 7.6 6.6 7.0 7.6 6 .6 7.0 4.3 IC, 2 sta ge (s) IF (s) 3.6 4 .1 3.4 3.6 4.0 3.4 2.3 pO queue free % 98 97 98 93 100 100 99 cM capacity (vehhl) 281 274 660 383 276 914 895 laiia-~-, ES.W:WB ~.vs~ REn i;re2 -s Volume Total 24 26 4 109 117 320 Volume Left 5 26 0 7 0 3 Volume Right 11 0 4 0 16 0 14 cSH 370 383 914 895 1700 1340 1700 Volume to Capacity 0.07 0.07 0.00 0.01 0.07 0.00 0.19 Queue Length 95th (ft) 5 6 0 1 0 0 0 Control Delay (s) 15.4 15.1 9.0 0.7 0 .0 0.1 0.0 Lane LOS C C A A A Approach Delay (s) 15.4 14.2 0.3 0.0 Approach LOS C B lnlersedion ~umma Average Delay 1.0 Intersection Capacity Utilization 31.5% ICU Level of Service Analysis Period (min) 15 M:\07\07193 RSD Tra nsporta tion Cen ler\Synchro\Exi s ling PM Peak Hour.sy7 The Transpo Group Existing PM Peak Hour 6/2512007 t ~ \. ! .,' NBT NBR SSC-SBT SB 41> 41> Free Free 0% 0% 193 15 3 602 13 0 .95 0.95 0.95 0.95 0.95 203 16 3 634 14 660 2 19 2 19 4.2 2.2 100 1340 A Synchro 6 Report . HCM Signalized Intersection Capacity Analysis Existing AM Peak Hour Plus Project 3: North 4 th Street & Park Avenue North ,) -t .(" -'-~ t Movement~ EBC-EBT EBR WBl WBT ~WBR NBL~BT Lane Configurations 4 tt I' .rt Ideal Flow (v phpl) 1900 1900 1900 1900 1900 1900 1900 1900 Total Lost time (s) 4 .0 4.0 4.0 Lane Util. Factor 0 .91 1.00 0 .95 Frt 1.00 0.85 1.00 Flt Protected 1.00 1.00 1.00 Said. Flow (prot) 4870 1524 3469 Flt Permitted 1.00 1.00 0.95 Satd. Flow (eerm) 4870 1524 3306 Volume (vph) 0 0 0 94 864 65 7 527 Peak-hour factor. PHF 0.91 0.91 0.91 0.91 0.91 0.9 1 0.91 0.91 Adj. Flow(vph) 0 0 0 103 949 71 8 579 RTOR Reduction (vph ) 0 0 0 0 0 39 0 0 Lane Group Flow ( vph) 0 0 0 0 1052 32 0 587 Hea~ Vehicles (%) 0% 0% 0% 6% 6% 6% 4% 4% Turn Type Perm Perm Perm Protected Phases 8 2 Permitted Phases 8 8 2 Actuated Green, G (s) 41 .0 41.0 41.0 Effective Green, g (s) 41.0 41 .0 41.0 Actuated g/C Ratio 0.46 0.46 0.46 Clearance T ime (s) 4.0 4.0 4.0 Vehicle Extension (s) 3 .0 3.0 3.0 Lane Grp Cap (vph) 2219 694 1506 vis Ratio Prat vis Ratio Perm 0 .22 0.02 c0.18 vie Ratio 0 .4 7 0.05 0.39 Uniform Delay, d1 17.0 13.6 16.2 Progression Factor 1.0 0 1.00 1.00 Incremental Delay, d2 0 .7 0.1 0 .8 Delay (s) 17 .7 13.8 17.0 Lev el of Service B B B Approach Delay (s ) 0 .0 17 .5 17.0 Approach LOS A B B lnbii'seCtion Suminaiv ·;.."'-·· HCM Average Control Delay 16.7 HCM Level of Service HCM Volume to Capacity ratio 0 43 Actuated Cycle Length ( s) 90.0 Sum of lost ti me (s) Intersection Capacity Utiliza tion 43.4 % ICU Level of Service Analysis Period (min) 15 C Critical Lane Group M:\07\07 193 RSD Transportation Center\Synchro\With-Project AM Peak Hour .sy7 Th e Transpo Group 7i 11 i 2007 ,.. '. + ..,, NBR-s~SBT SBR: t t r 1900 1900 1900 1900 4.0 4.0 0.95 1.00 1.00 0.85 1.00 1.00 3252 1455 1.00 1.00 3252 1455 0 0 103 36 0.9 1 0.9 1 0 .91 0.91 0 0 113 40 0 0 0 0 0 0 113 40 4 % 11 % 11 % 11 % Free 6 Free 41.0 90.0 41 .0 90.0 0.46 1.00 4.0 3.0 1481 1455 0 .03 0.03 0 .08 O.Q3 13.8 0.0 1.00 1.00 0.1 0.0 13.9 0.0 B A 10.3 B I B 8.0 A Synchro 6 Report HCM Unsi gnal ized Intersection Capacity Analysis Existing AM Peak Hour Plus Project 6: N orth 5th Street & Park A v enue North ,) -t .(" -'-"' t ,.. t..l ovement EBC EBr-EBR -wsr: W13T WBR -RBLrlBINBR Lane Configurations 4> l!. t, 4 1> Sign Control Stop Stop Free Grade 0% 0% 0% Volume (veh/h) 4 6 8 0 0 7 3 596 Peak Hour Factor 0.85 0.85 0 .85 0.85 0.85 0.85 0.85 0.85 Hourly fl ow rat e (vph) 5 7 9 0 0 8 4 701 Pedestrians Lane Width (ft) Walking Speed (ft/s) Percent Blockage Right tum flare (veh) Median type None None Median storage veh) Upstream signal (ft) 660 pX, platoon unblocked 0.93 0 .93 0.93 0.93 0.93 vC, conflicting volume 528 907 74 828 889 369 148 vC 1, stage 1 cont vol vC2 , stage 2 conf vol vC u , unblocked vol 420 827 74 742 807 249 148 tC, single (s) 7.5 6.5 6.9 7 .6 6.6 7.8 4.2 tC. 2 stage (s) tF (s) 3 .5 4.0 3.3 3.6 4.1 3.8 2.2 pO que ue free % 99 98 99 100 100 99 100 cM capacity (veh/h) 476 285 979 265 280 588 1424 DlrectiOR~ne #· EBii~ 1-wa ~NSf'"".'NB 2-SB t .,.SB 2 Volume Total 21 0 8 354 387 81 74 Volum e Left 5 0 0 4 0 7 0 Volume Right 9 0 8 0 36 0 0 cSH 478 1700 588 1424 1700 829 1700 Volume to Capacity 0.04 0.00 0.01 0.00 0.23 0.01 0.04 Queue Length 95th (ft ) 3 0 1 0 0 1 0 Control Delay (s) 12.9 0.0 11 .2 0.1 0.0 0.9 0.0 Lane LOS B A B A A Approach Delay (s) 12.9 11 .2 0.0 0 .5 Approach LOS B B Intersection Summa!JI'. Average Delay 0 .5 Intersection Capacity Utilization 30.7% ICU Level of Service Analysis Period (m in) 15 M :\07\07193 RSD Tra nsportation Center\Synchro\With-Proj ect AM Peak Hour.sy7 The Transpo Group 31 0.85 36 - A 7/11i2007 '. + .; SB[ se.----sBR 4f. Free 0% 6 126 0 0.85 0.85 0.85 7 148 .0 0 .93 738 645 4.3 2.3 99 829 Synchro 6 Report HCM U n s ignalized Inter section Capacity Analysi s Existing AM Peak Hour P lu s Project 11 : Site Drivewa;i: & Garden Avenue North .,} ,. ~ t ! ~ ovemerit ESLEBR NB[ NBT SBT~SBR Lane Configurations V "I t f. Sign Control Stop Free Free Grade 0% 0% 0 % Volume (veh/h) 15 75 0 153 33 0 Peak Hour Factor 0.92 0.92 0.92 0.92 0.92 0.92 Hour1y flow rate (vph) 16 82 0 166 36 0 Pedestrians Lane Width (ft) Walking Speed (ft/s) Percent Block age Right tum flare (veh) Median type None Median storage veh) Upstream signal (ft) pX, platoon unblock ed vC, conflicting volume 202 36 36 vC 1, stage 1 conf vol vC2, stage 2 conf vol vCu. unblocked vol 202 36 36 IC, single (s ) 7 .4 7.2 4 .1 tC. 2 stage (s) tF (s) 4.4 4.2 2.2 pO queue free % 97 90 100 cM capacity (veh/h) 609 8 15 1588 Olrac:tioni[iiii i -~ ~ NB 1-NB'2 sB·1- Volume Total 98 0 166 36 Volume Left 16 a a 0 Volume Right 82 0 0 0 cSH 771 1700 1700 1700 Volume to Capacity 0.13 0.00 0.10 0.02 Queue Length 95th (ft) 11 0 0 0 Control Delay (s) 10.3 0.0 0 .0 0.0 Lane LOS B Approach Delay (s) 10.3 0.0 0.0 Approach LOS B Average Delay 3.4 Intersection Capacity Utilization 20.2% ICU Level of Service Ana lysis Period (min) 15 M :\07107 193 RSD Transportation Center\Synchro\With-Pro1ect AM Peak Hour.sy7 The Transpo Group 7/11/2007 A Synchro 6 Report I HCM U n s ignalized Intersection Capacity Analysis Existing AM Peak Hour Plus P roject 13: North 5th Str eet & S ite Drivewa;i: -,. ~ -~ ~ l.4ovement EBT EBR WB[ WBT,.~B[ NBR Lane Configurations f. +T Sign Control Free F ree Stop Grade 0% 0% 0% Volume (veh/h) 4 3 3 a 7 0 a Peak Hour Factor 0.85 0.85 0.85 0.85 0.85 0.85 Hour1y flow rate (vph) 5 1 4 a 8 a a Pedestrians Lane Width (ft) Walking Speed (ft/s) Percent Blockage Right tum flare (veh ) Median type None Median storage veh) Upstream signal (ft) pX, platoon unblocked vC, conflicting volume 54 61 52 vC 1, stage 1 conf vol vC2, stage 2 conf vol vCu. un blocked vol 54 6 1 52 tC. single (s) 4.1 6.4 6.2 tC. 2 stage (s) tF (s) pO queue free % c M capacity (veh /h) Volume Left Volume Right cSH 1700 1564 Volume to Capacity 0.03 0.00 Queue Length 95th (ft ) 0 0 Ccntrol Delay (s) 0.0 0.0 Lane LOS Approach Delay (s) 0.0 0.0 Approach LOS Intersection Summ Average Delay a.a Intersection Capacity Utilization 6 .7% ICU Level of Service Analys is Period (min) 15 M:\07107 193 RSD Transportation Center\Synchro\With-Project AM Peak Hour.sy7 The Transpo Group 7/11 /2007 A Synchro 6 Report HCM Unsi gnal ized Intersection Capacity Analysis Exi sting AM Peak Hour Plus Project 15: S i te D ri vewa:i;: & Park Avenue North ~ '-t ,.. \. ! ovement WBl WBR NBT NBR SBL SBT Lane Configurations V ti. .ft Sign Control Stop Free Free Grade 0% 0% 0% Volume (veh/h) 13 1 617 97 6 131 Peak Hour Factor 0.91 0 .91 0.9 1 0.91 0.91 0.91 Hourly flow rate (vph) 14 1 678 107 7 144 Pedestrians Lane Width (ft) Walking Speed (IVs ) Percent Blockage Right tum flare (veh) M edian type None M edian storage veh) Upstream signal (ft) 379 pX, platoon unblocked 0.90 0.90 0.90 vC, conflicting volume 816 392 785 vC 1, stage 1 cont vo l vC2, stage 2 cont vol vCu. unblocked vol 680 207 644 tC, single (s) 6.8 6.9 4 .1 tC, 2 stage (s ) tF (s) 3.5 3.3 2.2 pO queue free % 96 100 99 cM capacity (veh/h) 346 722 852 B1 NB2 88'1 SB 2 Volume Total 15 452 333 55 96 Volume Left 14 0 0 7 0 Volume Right 1 0 107 0 0 cS H 360 1700 1700 852 1700 Volume to Capacity 0.04 0.27 0 .20 0.01 0 .06 Queue Le ng th 95th (ft) 3 0 0 1 0 Control Delay (s) 15.5 0.0 0.0 1.2 0 .0 Lane LOS C A Approach Delay ( s) 15.5 0.0 0.4 Approach LOS C onSummaiv . ~!;• Average Del ay 0.3 Intersection Capacity Utilization 30.1% ICU Level of Service Analysis Period (min) 15 M:\07\07193 RSD Transportation Cen te r\Synchro\With-Project AM Peak Hour.sy7 The Transpo Group 7/11/2007 I -, ! A Synchro 6 Report HCM Unsignalized Inter section Capacity A n alysis Existing AM Peak Hour Plus Project 17: N orth 4th Str eet & S ite Dri vewal _,> --'-\. .' Movement EBC EBT WBT W8R .SBL SBR Lane Configurations tilt. Sign Control Free Free Stop Grade 0% 0% 0% Volume (veh/h) 0 0 1023 0 0 0 Peak Hour Factor 0 9 1 0.91 0.9 1 0 .9 1 0 .91 0.9 1 Hourly ftow rate (vph) 0 0 1124 0 0 0 Pedestrians Lane Width (ft) Walking Speed (IVs ) Percent Blockage Right tum flare (veh) Median type None Median storage veh) Upstream signal (ft) 21 3 pX, platoon unblocked vC, conflicting volume 11 24 1124 281 vC 1, stage 1 cont vo l vC2, stage 2 cont vol vCu, unblocked vo l 1124 11 24 28 1 tC, single (s) 4.1 6.8 6.9 tC, 2 stage (s ) tF (s) 2.2 3.5 3.3 pO queue free % 100 cM capacity (vehlh) 629 C>lrec:IIOn, Cine i WS'll Volume Total 32 1 Volume Left 0 Volume Right 0 cSH 1700 1700 1700 1700 Volume to Capacity 0.19 0 .19 0.19 0 .09 Queue Length 95th (ft) 0 0 0 0 Control Delay (s) 0.0 0.0 0.0 0.0 La ne LOS Approach Delay (s) 0.0 Approach LOS fiiiii Average Delay 0.0 Intersection Capacity Utilization 18.2% ICU Leve l of Service Analysis Period (m in) 15 M:\07\07193 RSD Transportation Center\Synchro\With-Project AM Peak Hour.sy7 The Transpo Group 7/11 /2007 A Synchro 6 Report HCM Signalized Intersection Capacity Analysis Existing PM Peak Hour Plus Project 3: North 4th Street & Park Avenue North / -~ ,(' +-\.. ~ t ~ !l,(ovement EB[ EBT~ EBR we1.-w eT--WBR-NBL1-lBT--i;reR Lane Configurations <ttt .,, <ft Ideal Flow (vphpl ) 1900 1900 1900 1900 1900 1900 1900 1900 Total Lost time (s ) 4.0 4.0 4.0 Lane Util . Factor 0.91 1.00 0.95 Frt 1.00 0.85 1.00 Flt Pro1ected 0 .99 1.00 1.00 Sat d. Flow (prot) 5066 1599 3266 Flt Permitted 0 .99 1.00 0.90 Sat d. Flow (~rm) 5066 1599 2941 Volume (vph) 0 0 0 245 640 23 19 179 Peak-hour factor. PHF 0.98 0 .98 0.98 0.98 0 .98 0.98 0.98 0.98 Adj. F low (vph) 0 0 0 250 653 23 19 183 RTOR Reduc tion (vph) 0 0 0 0 0 13 0 0 Lane Group Flow (vph) 0 0 0 0 903 10 0 202 Heav~ Vehicles(%) 0% 0 % 0% 1% 1% 1% 10% 10% Turn Type Perm Perm Perm Protected Phases 8 2 Permitted Phases 8 8 2 Actuated Green, G (s) 4 1.0 41 .0 41 .0 Effective Green, g (s) 4 1.0 41 .0 41.0 Actuated g/C Ratio 0.46 0.46 0.46 Clearance nme (s) 4.0 4.0 4.0 Vehicle Ext ension (s) 3 .0 3.0 3.0 Lane Grp Cap (vph) 2308 728 1340 v/s Ratio Prot v/s Ratio Perm 0.18 0.01 O.Ql 0 39 0.01 0.15 16.2 13.4 14.3 1.00 1.00 1.00 0.5 0.0 0 .2 16.7 13.5 14 .6 B B B 0 .0 16.7 14.6 A B B HCM Average Control Delay 15.5 HCM Level of Service HCM Volume to Capacity ratio 0.36 Actuated Cycle Length (s) 90.0 Sum of lost time (s) Intersection Capacity Utilization 43.7% IC U Level of Service Analysis Period (min) 15 C Critical Lane Group M:107\07193 RSD Transportation Center\Synchro\With-Project PM Peak Hour.sy7 The Transpo Group 1900 0 0.98 0 0 0 10% B 8 .0 A 7/11 /2007 '. ! .,' SBL SBT SBR tt .,, 1900 1900 1900 4.0 4.0 0.95 1.00 1.00 0.85 1.00 1.00 3505 1568 1.00 1.00 3505 1568 0 526 88 0 .98 0.98 0 .98 0 537 90 0 0 0 0 537 90 3% 3% 3% Free 6 Free 41 .0 90.0 41.0 90.0 0 .46 1.00 4.0 3.0 1597 1568 c0.15 0.06 0 .34 0.06 15.8 0.0 1.00 1.00 0.6 0.1 16.3 0.1 B A 14.0 B Synchro 6 Report HCM Un si gnal ized Intersecti on Capacity Analysis Existing PM Peak Hour Plus Projec t 6: North 5th Street & Park Avenue North / -~ ,(' +-\.. ~ t ,Movement EB[ EBT EBR WBl WBT WBR NBl NBT Lane Configurations .;. "I f. <ff. Sign Control Stop Stop Free G rade 0% 0% 0% Volume (veh/h) 5 8 10 25 0 4 7 192 Peak Hour Factor 0.95 0 .95 0.95 0.95 0.95 0 .95 0 .95 0.95 Hou~y flow rate (vph) 5 8 11 26 0 4 7 202 Pedestrians Lane Width (ft) Walking Speed (ft/s) Percent Blockage Right tum flare (veh) Median type None None Median storage veh) Upst ream signal (ft ) 660 pX. platoon unblocked vC, conflicting volume 769 884 324 566 882 110 647 vC 1, stage 1 cont vol vC2, stage 2 cont vol vCu, unblocked vo l 769 884 324 566 882 110 647 tC, single (s) 7.6 6.6 7.0 7.6 6.6 7.0 4.3 tC , 2 stage (s) t F (s) 3.6 4.1 3 .4 3 .6 4.0 3.4 2 .3 pO queue free % 98 97 98 93 100 100 99 cM ca pacity (veMl) 280 273 660 382 275 9 13 895 Diredicinit:"ane # EBJ1,.<WB1 WB2 N87d,NB2 SBT SB Volume Total 24 26 4 108 119 321 331 Volume Left 5 26 0 7 0 4 0 Volume Right 11 0 4 0 18 0 14 cSH 369 382 913 895 1700 1339 1700 Volume to Capacity 0.07 0 .07 0.00 0 .01 0.07 0.00 0.19 Q ueue Length 95th (ft) 5 6 0 1 0 0 0 Control Delay (s) 15.4 15.1 9 .0 0.7 0.0 0.1 0 .0 Lane LOS C C A A A Approach Delay (s) 15.4 14.3 0 .3 0.1 Approach LOS C B lnie Average Delay 1.0 Intersection Capacity Utilization 32.2% ICU Level of Service Analysis Period (min) 15 M:107\07193 RSD Transportation Center\Synchro \With-Project PM Peak Hour.sy7 The Transpo Group 7/11/2007 ~ '. ! ~ NBR Free 0% 17 4 602 ~ 0.95 0 .95 0.95 0.95 18 4 634 14 220 220 4.2 2.2 100 1339 A Synchro 6 Report HCM Unsigna lized Intersection Ca pacity Analysis Existing PM Peak H o u r P lus Project 9 : North 5th Street & Site Driveway -\' (' -..., ,,. lovmnent ., EBT e·BR WBL: WBT NBL NBR Lane Configurations 1+ 4 Sign Control Free Free Stop Grade 0% 0% 0% Volume (veh/h) 29 0 0 29 0 0 Peak Hour Factor 0 .95 0.95 0 .95 0.95 0.95 0.95 Hourty flow rate (vph) 31 0 0 31 0 0 Pedestrians Lane Width (ft) Walk ing Speed (lt/s) Percent Blockage Right tum flare (veh ) Median type None Median storage veh ) Upstream signal (ft) pX, platoon unblocked vC, conflicting volume 31 61 31 vC 1. stage 1 con I vol vC2, stage 2 con! vo l vCu. unblocked vol 31 61 31 tC. single (s ) 4.1 6.4 6.2 IC, 2 stage (s ) tF (s) 2.2 3.5 3.3 pO queue free % 100 100 100 cM capacity (vehlh) 1595 950 1050 15trecuon;.Cane # ee·1 WB 1 V olume Total 3 1 31 Volume Left 0 0 Volume Right a 0 cSH 1700 1595 Volume to Capacity 0.02 0.00 Queue Length 95th (ft) a 0 Control Delay (s) 0.0 0.0 Lane LOS Approach Delay (s) a.a a.a Approach LOS nlelsection Summ, Average Delay 0.0 Intersection Capacity Utilization 6.7% ICU Level of Service Analysis Period (min) 15 M:\07\07193 RSD T ransportation Center\Synchro\With -Project PM Peak Hour.sy7 The Transpo Group 711112007 ' I A Synchro 6 Report HCM Unsignalize d Intersection Capacity A nalysis Existing PM Peak Hour P l us Project 11: Site Driveway & Park Avenue North (' '-t ,,. '. ! Movement WBL~WB~BT~NBR SBr: SST Lane Configurations ¥ tt+ .rt Sign Control Stop Free Free Grade 0% 0% 0% Volume (veh/h) 29 3 200 6 1 622 Peak Hour Factor 0.98 0.98 0.98 0 .98 098 0.98 Hourty flow rate (vph) 30 3 204 6 1 635 Pedestrians Lane Width (ft ) Walking Speed (tUs) Percent Blockage Right tum flare (veh ) Median type None Median storage veh) Upstream s ignal (ft) 369 pX, platoon unblocked vC, confli cting vo lume 527 105 2 10 vC 1. stage 1 co n! vol vC2 , stage 2 cont vol vCu. unblocked vol 527 105 210 tC, single (s) 6.8 6.9 4.1 IC , 2 stage (s) tF (s) 3.5 3.3 2.2 pO queue free % 94 100 cM capacity (vehlh) 486 936 Pliiclioii;:uine # WB)!e:RBI N~ Volume Total 33 136 74 Volume Left 30 0 0 Volume Right 3 a 6 cS H 509 1700 1700 Volume to Capacity 0.06 0 .08 0.04 Queue Length 95th (ft) 5 a a Control Delay (s) 12.6 0.0 0.0 Lane LOS B A Approach Delay (s) 12.6 0.0 0.0 Approach LOS B Average Delay 0.5 Intersection Capacity Utilization 27.9% ICU Level of Service Analysis Period (min) 15 M:\07\07193 RSD Transportation Center\Synchro\With-Project PM Peak Hour.sy7 The Transpo Group 7111 /2007 A Synchro 6 Report HCM Unsignalized Intersection Capacity Analysis Existing PM Peak Hour Plus Project 15: Site D r ivewa:z:: & Garden Aven ue N o rth ..> t ~ t ! .,, lovement , ~EBR NBC Nsr--saT~SBR Lane Configurations V "'i t l+ Sign Control Stop Free Free Grade 0% 0% 0 % Volume (veh /h ) 0 0 1 50 156 21 Peak Hour Factor 0.92 0 .92 0.92 0.92 0 .9 2 0 .92 Hour1y flow rate (vph) 0 0 1 54 170 23 Pedestrians Lane Width (ft) Walking Speed (ft/s) Percent Blockage Right tum fl are (veh) Median type None Median storage veh) Upstream signal (ft) pX , platoon unblocked vC. conflicting volume 238 181 192 vC 1, stage 1 conf vol vC2, stage 2 conf vol vCu. unblocked vol 238 181 192 IC, single (s) 6 .4 6.2 5.1 tC, 2 stage (s) tF (S) 3.5 3.3 3.1 pO queue free % 100 100 100 cM capacity (veh/h) 754 867 960 1Jrectlori. t.:ane # EB 1 NB '1 NB2 SB 1 Volume Total 0 1 54 192 Volume Left 0 1 0 0 Volume Right 0 0 0 23 cSH 1700 960 1700 1700 Volume to Capacity 0 .00 0.00 0.03 0 .11 Queue Length 95th (ft) 0 0 0 0 Control Delay (s) 0.0 8.8 0.0 0 .0 Lane LOS A A Approach Delay (s) 0 .0 0.2 0.0 Approach LOS A .Intersection Summa~ Average Delay 0.0 Intersection Capacity Utilization 12.8% ICU Level of Service Analysis Period (min) 15 M:\0 7\07193 RSD Transportation Center\Synchro\With-Project PM Peak Hour.sy7 The Transpo Group 7/11 /2007 ! A Synchro 6 Report H CM Unsignalized Intersection Capacity Analysis Existing PM Peak Hour Plus Project 17: North 4th Str eet & S ite D r ive wa:z:: ..> --'-'. .,, La ne Configu rations Sign Control Free Free Stop Grade 0% 0% 0% Volume (veh/h) 0 0 908 8 0 0 Peak Hour Factor 0 .98 0.98 0.98 0 .98 0.98 0.98 Hourly fl ow rate (vph) 0 0 927 8 0 0 Pedestrians La ne Width (ft) Walking Speed (ft/s) Percent Blockage Right tu m flare (veh) Median type None Median storage veh) Upstream signal (ft) 233 pX , platoon unblock ed vC , conflicting volume 935 931 236 vC 1, stage 1 c on f vol vC2, stage 2 conf vol vCu , unblocked vol 935 931 236 IC , single (s) 4 .1 6.8 6.9 tC. 2 stage (s) tF (s) 2.2 3.5 3.3 p0 que ue free % 100 100 100 cM ca pacity (veh/h) 741 270 772 Direction; lar Volume Tota l V olume Left Volume Right cSH Volume to Capacity Queue Length 95th (ft) 0 0 0 0 Control Delay (s) 0.0 0.0 0.0 0.0 Lane LOS Approach Delay (s) 0.0 Approach LOS Intersection Surnm!!!}'. A verage Delay 0.0 Intersection Capacity Utilization 16.6% ICU Level of Service Analysis Period (m in) 15 M:\07\07 19 3 RSD Transportation Center\Synchro\With-Proj ect PM Peak Hour .sy7 The Transpo Group 7/11 /2007 A Synchro 6 Repart Geotechnical Engineering ~->~ Water Resources ., '.,. ••• ': , .. , .... . , ,: .• ' ..... 1. . '·~' ·, .,,.,,,'"':•· 9 I _.., ',, .'. '!-', -"'' .. . .... ,, Environmental Assessments and Remediation Associated Earth Sciences, Inc. &i/rt'to'!f 2_,f '(/t!t'll:f' qiJt1tVIC6' Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report NEW TRANSPORTATION CENTER Renton, Washington Prepared for Renton School District No. 403 Project No. KE070040A June 14, 2007 Sustainable Development Services Geologic Assessments RSD 403 R SEP 2 0 2007 D I::. G t:. I V t: r:APIT AL PROJECTS I I I I I I I I I I I I I I I I I I I Associated Earth Sciences, Inc. ~w~~~ Cefe6rafi11J Over 2!j 1jears of.Service June 14, 2007 Project No. KED70040A Renton School District No. 403 Capital Projects Office 1220 North 4th Street Renton, Washington 98055 Attention: Mr. Stewart L. Shusterman Subject: Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report New Transportation Center 1220 North 41h Street Renton, Washington Dear Mr. Shusterman: We are pleased to present the enclosed copies of the above-referenced report. This report summarizes the results of our subsurface exploration, geologic hazard, and geotechnical engineering studies and offers recommendations for the design and development of the proposed project. The report revision reflects the alternate foundation and floor support options proposed during the value engineering process. We have enjoyed working with you on this study and are confident that the recommendations presented in this report will aid in the successful completion of your project. If you should have any questions or if we can be of additional help to you, please do not hesitate to call. Sincerely, ASSOCIATED EARTH SCIENCES, INC. Kirkland, Washington Kurt D. Merriman, P.E. Principal Engineer KD\1/ld KE070040A4 -Projects\20070040\KE\WP Kirkland 425-827-7701 • Everett • Tacon1a 425-259-0522 253-722-2992 www.aesgeo.com REVISED SUBSURFACE EXPLORATION, GEOLOGIC HAZARD, AND GEOTECHNICAL ENGINEERING REPORT NEW TRANSPORTATION CENTER Renton, Washington Prepared for: Renton School District No. 403 Capital Projects Office 1220 North 4'h Street Renton, Washington 98055 Prepared by: Associated Earth Sciences, Inc. 911 5th Avenue, Suite 100 Kirkland, Washington 98033 425-827-7701 Fax: 425-827-5424 June 14, 2007 Project No. KE070040A New Transportation Center Renton, Washington 1.0 INTRODUCTION Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report Project and Site Conditions I. PROJECT AND SITE CONDITIONS This report presents the results of our revised subsurface exploration, geologic hazard, and geotechnical engineering study for the proposed New Transportation Center to be located at 1220 North 4th Street in Renton, Washington. The report revision reflects the alternate foundation and floor support options proposed during the value engineering process. The site location is presented on Figure 1, "Vicinity Map." The proposed building location and approximate locations of the explorations accomplished for this study are presented on the "Site and Exploration Plan," Figure 2. In the event that any changes in the nature, design, or location of the structure are planned, the conclusions and recommendations contained in this report should be reviewed and modified, or verified, as necessary. 1. 1 Purpose and Scope The purpose of this study was to provide subsurface data to be utilized in the design and development of the aforementioned project. The study included drilling six test borings and performing geologic studies to assess the type, thickness, distribution, and physical properties of the subsurface sediments and ground water conditions. Geologic hazard evaluations and engineering studies were also conducted to determine suitable geologic hazard mitigation techniques, the type of suitable pile foundation, pile design recommendations, anticipated settlements, floor support recommendations, and site preparation and drainage considerations. This report summarizes our current fieldwork and offers geologic hazard mitigation and development recommendations based on our present understanding of the project. 1.2 Authorization Written authorization to proceed with this study was granted by Mr. Stewart Shusterman of the Renton School District No. 403 (District). Our study was accomplished in general accordance with our scope of work letter dated January 23, 2007. This report has been prepared for the exclusive use of the District and their agents for specific application to this project. Within the limitations of scope, schedule, and budget, our services have been performed in accordance with generally accepted geotechnical engineering and engineering geology practices in effect in this area at the time our report was prepared. Our observations, findings, and opinions are a means to identify and reduce the inherent risks to the owner. No other warranty, express or implied, is made. June 14. 2007 ASSOCIATED EARTH SCIENCES, INC. SGR!ld-KE07004fJA4 ProJectsl2007004fJ\KE\WP Page 1 New Transportation Center Renton, Washington 2.0 PROJECT AND SITE DESCRIPTION Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Project and Site Conditions This report was completed with an understanding of the project based on a preliminary building layout and site plan provided by the District. The project site is the existing District transportation center. The site is located at 1220 North 4'h Street in downtown Renton, Washington. The existing property includes a large warehouse building at the southeast corner with a two-story office building to the northwest of the warehouse. A third small building is located near the north end of the property. The remainder of the site is either surfaced with gravel or asphalt, which is in poor condition. The paved areas are primarily used for bus parking. The gravel parking area to the west of the office building is used for employee parking. We understand that present plans call for demolishing existing buildings and constructing a new lightly loaded administrative building near the west-central portion of the site. The existing gravel parking area near the north end of the site and drive/parking areas surrounding the new building will also be paved. The new building footprint will encompass approximately 18,000 square feet. We have not been provided with a grading plan or any details on the building construction or loading conditions. Therefore, we have assumed that site grades will remain close to present grades and that the new structure will be a two-story, wood-framed building with light to moderate foundation loads. 3.0 SUBSURFACE EXPLORATION Our field study included drilling six exploration borings with a truck-mounted drill rig to gain subsurface information about the site, and collecting soil samples. The various types of sediments, as well as the depths where characteristics of the sediments changed, are indicated on the exploration logs presented in the Appendix to this report. The depths indicated on the boring logs where conditions changed may represent gradational variations between sediment types in the field. If changes occurred between sample intervals in our borings, they were interpreted. Our explorations were approximately located in the field by measuring from known site features shown on an aerial photograph of the site with the proposed building location overlain on the photograph. The conclusions and recommendations presented in this report are based on the six explorations completed for this study. The number, type, locations, and depths of the explorations were completed within site and budgetary constraints. Because of the nature of exploratory work below ground, extrapolation of subsurface conditions between field explorations is necessary. It should be noted that differing subsurface conditions are sometimes present due to the random nature of deposition and the alteration of topography by June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB!ld -KE070040A4 -Projecrs\2007004{)\KEl WP Page 2 New Transportation Center Renton, Washington Revised Subsuiface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Project and Site Conditions past grading and/or filling. The nature and extent of any variations between the field explorations may not become fully evident until construction. If variations are observed at that time, it may be necessary to re-evaluate specific recommendations in this report and make appropriate changes. 3 .1 Exploration Borings The exploration borings were completed by advancing a 33/,-inch, inside-diameter, hollow- stem auger with a truck-mounted drill rig to depths ranging from 45 to 95 feet. Below the water table, the borings were successfully completed with little or no heaving conditions with water stabilization drilling techniques. During the drilling process, samples were obtained at generally 5-foot-depth intervals. The borings were continuously observed and logged by a geotechnical engineer or engineering geologist from our firm. The exploration Jogs presented in the Appendix are based on the field logs, drilling action, and inspection of the samples secured. Disturbed, but representative samples were obtained by using the Standard Penetration Test procedure in accordance with American Society for Testing and Materials (ASTM):D 1586. This test and sampling method consists of driving a standard 2-inch, outside-diameter, split- barrel sampler a distance of 18 inches into the soil with a 140-pound hammer free-falling a distance of 30 inches. The number of blows for each 6-inch interval is recorded, and the number of blows required to drive the sampler the final 12 inches is known as the Standard Penetration Resistance ("N") or blow count. If a total of 50 is recorded within one 6-inch interval, the blow count is recorded as the number of blows for the corresponding number of inches of penetration. The resistance, or N-value, provides a measure of the relative density of granular soils or the relative consistency of cohesive soils; these values are plotted on the attached boring logs. The samples obtained from the split-barrel sampler were classified in the field and representative portions placed in watertight containers. The samples were then transported to our laboratory for further visual classification and laboratory testing, as necessary. 3 .2 Laboratory Tests We performed percent passing the No. 200 sieve analysis by ASTM Method D 1140 on all samples collected from exploration boring EB-I for liquefaction hazard analysis. The results of these tests are presented in the Appendix following the exploration logs. June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB!ld -KE070040A4 Projects\20070040\KEl WP Page 3 New Transportation Center Renton, Washington 4.0 SUBSURFACE CONDITIONS Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Repor1 Project and Site Conditions The encountered soils were consistent with the geology mapped in the site area, as shown on the Geologic Map of King County, Washington by Booth et al., 2002. This map shows the site area is mantled by Quaternary alluvium deposited by the ancestral Cedar River. 4 .1 Stratigraphy Fill Man-placed fill, consisting of silty sand with gravel, was encountered in all explorations to depths of roughly 3 feet. The fill and the upper surface of the underlying alluvium are in a loose to medium dense condition. Quaternary Alluvium Sediments encountered beneath the asphalt and fill generally consisted of interbedded clean sand, silty sand, clayey and lean silt with occasional lenses of gravel, peat, and other organics scattered throughout the soil column. We interpret these sediments to be representative of recent and older alluvium deposited in former channels of the Cedar River. The alluvium extends beyond the depth of our deepest exploration (95 feet). In general, the alluvium is very loose/soft to medium dense to an average depth of about 75 feet throughout the building pad area. Below roughly 75 feet, the alluvium occurs in a dense condition and is relatively more granular. Conditions encountered in exploration boring EB-I were anomalous relative to the other explorations, as dense sediments were encountered at much shallower depths. The saturated soil in which "N" values do not exceed roughly 25 has a high potential for liquefaction-induced settlement. In addition, the abundant layers of very soft clayey and lean silt are subject to consolidation settlement under the new building loads. Therefore, structures will require deep pile foundations for support. In general, the soil where moisture content is within the compactable range is considered suitable for reuse as structural fill. It should be noted that where soils are above their optimum moisture content for compaction, their reuse as structural fill during all but the driest times of the year will be difficult. Existing alluvial soil was observed to contain silt and is considered moisture-sensitive. With appropriate remedial treatment, the soil, where moisture content is within the compactable range, may be considered suitable for support of slab-on-grade floors, hardscape, and paving. June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB!ld-KE070040A4 Projects\200700401KE\WP Page 4 New Transportation Center Renton, Washington 4.2 Hydrology Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report Proiect and Site Conditions Ground water was encountered at an average depth of 10 feet across the site corresponding roughly to Elevation 25 feet. However, ground water depths reported during drilling may not represent stabilized ground water elevations that would be recorded in a properly constructed monitoring well. Ground water encountered in our explorations represents the regional un- confined ground water aquifer within the Renton basin. Ground water may be encountered in excavations that penetrate into the underlying alluvial soils. To our knowledge, no deep cuts are planned that will intersect the regional ground water aquifer. If such cuts will be made, significant ground water dewatering operations will be necessary. It should be noted that fluctuations in the level of the ground water may occur due to the time of the year, variations in rainfall, and adjacent river levels. June I 4, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB/ld-KE070040A4 Projects\20070040IKE\WP Page 5 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report Geologic Hazards and Mitigations IL GEOLOGIC HAZARDS AND MITIGATIONS The following discussion of potential geologic hazards is based on the geologic, slope, and ground water conditions as observed and discussed herein. The discussion will be limited to seismic, landslide, and erosion hazards, including sediment transport. 5.0 SLOPE STABILITY HAZARDS AND RECOMMENDED MITIGATION Reconnaissance of this site was limited to the area shown on Figure 2. The site topography is relatively flat, and therefore the risk of landsliding is low. 6.0 SEISMIC HAZARDS AND RECOMMENDED MITIGATION Earthquakes occur in the Puget Sound Lowland with great regularity. Most of these events are small and are usually not felt by people. However, large earthquakes do occur, as evidenced by the most recent 6.8-magnitude event on February 28, 2001 near Olympia Washington; the 1965, 6.5-magnitude event; and the 1949, 7.2-magnitude event. The 1949 earthquake appears to have been the largest in this area during recorded history. Evaluation of return rates indicates that an earthquake of the magnitude between 5.5 and 6.0 is likely within a given 20-year period. Generally, there are four types of potential geologic hazards associated with large seismic events: I) surficial ground rupture, 2) seismically induced landslides, 3) liquefaction, and 4) ground motion. The potential for each of these hazards to adversely impact the proposed project is discussed below. 6. I Surficial Ground Rupture The nearest known fault trace to the project site is the Seattle Fault, located approximately 5 miles to the north. Recent studies by the U.S. Geological Survey (USGS; e.g., Johnson et al., 1994, Origin and Evolution of the Seattle Fault and Seattle Basin, Washington, Geology, v. 22, pp. 71-74; and Johnson et al., 1999, Active Tectonics of the Seattle Fault and Central Puget Sound Washington -Implications for Earthquake Hazards, Geological Society of America Bulletin, July 1999, v. Ill, n. 7, pp. 1042-1053) have provided evidence of surficial ground rupture along a northern splay of the Seattle Fault. The recognition of this fault splay is relatively new, and data pertaining to it are limited, with the studies still ongoing. According to the USGS studies, the latest movement of this fault was about 1,100 years ago June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGR!ld · KE070040A4 Projectsl200700401.KEIWP Page 6 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report Geologic Hazards and Mitigations when about 20 feet of surficial displacement took place. This displacement can presently be seen in the form of raised, wave-cut beach terraces along Alki Point in West Seattle and Restoration Point at the south end of Bainbridge Island. The recurrence interval of movement along this fault system is still unknown, although it is hypothesized to be in excess of several thousand years. Due to the suspected long recurrence interval and depth of loose/soft alluvium present within the site boundaries, the potential for surficial ground rupture is considered to be low during the expected life of the proposed structure. 6.2 Seismically Induced Landslides Reconnaissance of this site was limited to the area shown on Figure 2. The site topography is relatively flat to gently sloping, and therefore the risk of landsliding is low. 6. 3 Liquefaction We performed a liquefaction hazard analysis for this site in accordance with guidelines published in Seed & Idriss, 1982; Seed et. al, 1985; and Kramer, 1996. Our liquefaction analysis was completed with the aid of LiquefyPro computer software Version 4.3 by CivilTech Corporation. Liquefaction occurs when vibration or ground shaking associated with moderate to large earthquakes (generally in excess of Richter magnitude 6) results in loss of internal strength in certain types of soil deposits. These deposits generally consist of loose to medium dense sand or silty sand that is saturated (e.g., below the water table). Loss of soil strength can result in consolidation and/or lateral spreading of the affected deposit with accompanying surface subsidence and/or heaving. The liquefaction potential is dependent on several site-specific factors, such as soil grain size, density (modified to standardize field-obtained values), site geometry, static stresses, level of ground acceleration considered, and duration of the event. The earthquake parameters (a magnitude 7 .5 earthquake occurring directly beneath the site with a peak horizontal ground acceleration of 0.34g) used in our liquefaction analysis are in accordance with the required parameters set forth in the 2003 International Building Code (IBC). This level of acceleration is significantly greater than previously required by the Uniform Building Code (UBC). Figure 3 models the soil column, as identified in exploration boring EB-3, with a maximum ground water table of 7 feet during a design-level event. Figure 4 models the composite soil column, as identified in EB-3 and EB-4, with a maximum ground water table of 7 feet during a design-level event. Our analysis indicates that the site soils have a high risk of liquefaction above a depth of 32 feet in EB-3 and above a depth of 75 feet in EB-4 and EB-5. Conditions in EB-6 are similar to EB-4 and EB-5. Potential settlements ranging from roughly 10 to 29 inches were calculated for the site soil profile during a design-level event. It should be understood that June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB!/d" KE070040A4 Projeclsl200700401KE\ WP Page 7 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Geologic Hazards and Mitigations several soil properties used in the liquefaction analysis are estimated based on published data and engineering judgment. Therefore, these settlement estimates should be considered approximate and "worst-case scenarios." In addition to liquefaction settlement, the site soils are also subject to consolidation settlement under the new static building foundation loads (independent of seismic shaking). Therefore, we recommend that all building elements, including floor slabs and other structures, be supported on pile foundations. However, if the owner can assume the risk of potential liquefaction-induced settlements of this magnitude, the floor slab could be supported as a floating slab-on-grade. Pile foundations that extend to the minimum depths described in the "Design Recommendations" section of this report should reduce both consolidation settlement and seismically induced structure settlement to tolerable levels for new construction. Partial mitigation of the liquefaction risk could be provided by the use of a structurally reinforced mat foundation. The mat foundation would be subject to total and differential settlements that are considered greater than acceptable. The mat foundation would act as a "raft" below the structure to help reduce structural damage. Post-earthquake re-leveling may or may not be possible or practical, based on the settlement experience. A mat foundation will not mitigate consolidation settlement. We are available to provide more input on a mat foundation system, if requested. 6.4 Ground Motion Guidelines presented in the 2003 IBC should be used for structural design. Based on the exploration borings performed at the site, we interpret the subsurface conditions to correspond to a Site Class "F", as defined by Table 1615.1.1 of the 2003 IBC. Site Class "F" would apply to the site due to the potential for liquefiable soils. However, we anticipate that the period of vibration of the structure will be less than 0.5 second, which should be confirmed by the structural engineer. Therefore, we recommend using a Site Class "E" per Note b in Tables 1615.1.2(1) and 1615.1.2(2) of the 2003 IBC. The 2003 IBC seismic design parameters for short period (Ss) and I-second period (S1) spectral acceleration values were determined by the latitude and longitude of the project site using the USGS National Seismic Hazard Mapping Project website 1. Based on the more current 2002 data, the USGS website interpolated ground motions at the project site to be 1.43-g and 0.49g for building periods of 0.2 and 1.0 seconds, respectively, with a 2 percent chance of exceedence in 50 years. 7.0 EROSION HAZARDS AND RECOMMENDED MITIGATION As of October 1, 2006, the Washington State Department of Ecology (Ecology) Construction Storm Water General Permit (also known as the National Pollutant Discharge Elimination 1 http://eqdesign.cr.usgs.gov June I 4, 2007 ASSOCIATED EARTH SCIENCES, INC. SGBl!d -KE070040A4 Projws\200700401KE\WP Page 8 New Transportation Center Ren!on, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Geologic Hawrds and Mitigations System [NPDES] permit) requires weekly Temporary Erosion and Sedimentation Control (TESC) inspections for all sites 1 or more acres in size that discharge storm water to surface waters of the state. The TESC inspections must be completed by a Certified Erosion and Sediment Control Lead (CESCL) for the duration of the construction. TESC reports do not need to be sent to Ecology, but should be logged into the project Storm Water Pollution Prevention Plan (SWPPP). If the project does not require a SWPPP, the TESC reports should be kept in a file on-site, or by the permit holder if there is no facility on-site. Ecology also requires weekly turbidity monitoring by a CESCL of storm water leaving a site for all sites 5 acres or greater. Ecology requires a monthly summary report of the turbidity monitoring results (if performed) signed by the NPDES permit holder. If the monitored turbidity equals or exceeds 25 nephelometric turbidity units (NTU) (Ecology benchmark standard), the project best management practices (BMPs) should be modified to decrease the turbidity of storm water leaving the site. Changes and upgrades to the BMPs should be continued until the weekly turbidity reading is 25 NTU or lower. If the monitored turbidity exceeds 250 NTU, the results must be reported to Ecology within 24 hours and corrective action taken. Daily turbidity monitoring is continued until the corrective action lowers the turbidity to below 25 NTU. In order to meet the current Ecology requirements, a properly developed, constructed, and maintained erosion control plan consistent with the City of Renton standards and best management erosion control practices will be required for this project. Associated Earth Sciences, Inc. (AESI) is available to assist the project civil engineer in developing site-specific erosion control plans. Based on past experience, it will be necessary to make adjustments and provide additional measures to the TESC plan in order to optimize its effectiveness. Ultimately, the success of the TESC plan depends on a proactive approach to project planning and contractor implementation and maintenance. The erosion hazard of the site soils is moderate. The most effective erosion control measure is the maintenance of adequate ground cover. Maintaining cover measures atop disturbed ground provides the greatest reduction to the potential generation of turbid runoff and sediment transport. During the local wet season (October l" through March 31 "), exposed soil should not remain uncovered for more than 2 days unless it is actively being worked. Ground-cover measures can include erosion control matting, plastic sheeting, straw mulch, crushed rock or recycled concrete, or mature hydroseed. Flow-control measures are also essential for collecting and controlling the site runoff. Flow paths across slopes should be kept to less than 50 feet in order to reduce the erosion and sediment transport potential of concentrated flow. Ditch/swale spacing will need to be shortened with increasing slope gradient. Ditches and swales that exceed a gradient of about 7 to 10 percent, depending on their flow length, should have properly constructed check dams installed to reduce the flow velocity of the runoff and reduce the erosion potential within the June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGBl/d -KE070040A4 Projects\20070040\KEIWP Page 9 New Transponation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Geologic Hazards and Mitigations ditch. Flow paths that are required to be constructed on gradients between 10 to 15 percent should be placed in a riprap-lined swale with the riprap properly sized for the flow conditions. Flow paths constructed on slope gradients steeper than 15 percent should be placed in a pipe slope drain. AESI is available to assist the project civil engineer in developing a suitable erosion control plan with proper flow control. Some fine-grained surface soils are the result of natural weathering processes that have broken down parent materials into their mineral components. These mineral components can have an inherent electrical charge. Electrically charged mineral fines will attract oppositely charged particles and can combine (flocculate) to form larger particles that will settle out of suspension. The sediments produced during the recent glaciation of Puget Sound are, however, most commonly the suspended soils that are carried by site storm water. The fine-grained fraction of the glacially derived soil is referred to as "rock flour," which is primarily a silt-sized particle with little or no electrical charge. These particles, once suspended in water, may have settling times in periods of months, not hours. Therefore, the flow length within a temporary sediment control trap or pond has virtually no effect on the water quality of the discharge since it is not going to settle out of suspension in the time it takes to flow from one end of the pond to the other. Reduction of turbidity from a construction site is almost entirely a function of cover measures and flow control. Temporary sediment traps and ponds are necessary to control the release rate of the runoff and to provide a catchment for sand-sized and larger soil particles, but are very ineffective at reducing the turbidity of the runoff. Silt fencing should be utilized as buffer protection and not as a flow-control measure. Silt fencing is meant to be placed parallel with topographic contours to prevent sediment-laden runoff from leaving a work area or entering a sensitive area. Silt fences should not be placed to cross contour lines without having separate flow control in front of the silt fence. A swale/berm combination should be constructed to provide flow control rather than let the runoff build up behind the silt fence and utilize the silt fence as the flow-control measure. Runoff flowing in front of a silt fence will cause additional erosion and usually will cause a failure of the silt fence. Improperly installed silt fencing has the potential to cause a much larger erosion hazard than if the silt fence was not installed at all. The use of silt fencing should be limited to protect sensitive areas, and swales should be used to provide flow control. 7 .1 Erosion Hazard Mitigation To mitigate the erosion hazards and potential for off-site sediment transport, we recommend the following: June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB!ld -KE070040A4 -Projects\20070040\KE\ WP Page 10 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Geologic Hazards and Mitigations 1. The winter performance of a site is dependent on a well-conceived plan for control of site erosion and storm water runoff. It is easier to keep the soil on the ground than to remove it from storm water. The owner and the design team should include adequate ground-cover measures, access roads, and staging areas in the project bid to give the selected contractor a workable site. The selected contractor needs to be prepared to implement and maintain the required measures to reduce the amount of exposed ground. A site maintenance plan should be in place in the event storm water turbidity measurements are greater than the Ecology standards. 2. All TESC measures for a given area to be graded or otherwise worked should be installed prior to any activity within an area other than installing the TESC features or timber harvesting. The recommended sequence of construction within a given area after timber harvesting would be to install sediment traps and/or ponds and establish perimeter flow control prior to starting mass grading. 3. During the wetter months of the year, or when large storm events are predicted during the summer months, each work area should be stabilized so that if showers occur, the work area can receive the rainfall without excessive erosion or sediment transport. The required measures for an area to be "buttoned-up" will depend on the time of year and the duration the area will be left un-worked. During the winter months, areas that are to be left un-worked for more than 2 days should be mulched or covered with plastic. During the summer months, stabilization will usually consist of seal-rolling the subgrade. Such measures will aid in the contractor's ability to get back into a work area after a storm event. The stabilization process also includes establishing temporary storm water conveyance channels through work areas to route runoff to the approved treatment facilities. 4. All disturbed areas should be revegetated as soon as possible. If it is outside of the growing season, the disturbed areas should be covered with mulch, as recommended in the erosion control plan. Straw mulch provides the most cost-effective cover measure and can be made wind-resistant with the application of a tackifier after it is placed. 5. Surface runoff and discharge should be controlled during and following development. Uncontrolled discharge may promote erosion and sediment transport. Under no circumstances should concentrated discharges be allowed to flow over the top of steep slopes. 6. Soils that are to be reused around the site should be stored in such a manner as to reduce erosion from the stockpile. Protective measures may include, but are not limited to, covering with plastic sheeting, the use of low stockpiles in flat areas, or the June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGBl/d -KE070040A4-Projectsl20070040\KE\WP Page 11 New Transportation Center Renton, Washington Revised Subswface Exploration, Geologic Hazard, and Geotechnical Engineering Report Geologic Hamrds and Mitigations use of straw bales/silt fences around pile perimeters. During the period between October I" and March 31", these measures are required. 7. On-site erosion control inspections and turbidity monitoring (if required) should be performed in accordance with Ecology requirements. Weekly and monthly reporting to Ecology should be performed on a regularly scheduled basis. TESC monitoring should be part of the weekly construction team meetings. Temporary and permanent erosion control and drainage measures should be adjusted and maintained, as necessary, at the time of construction. It is our opinion that with the proper implementation of the TESC plans and by field-adjusting appropriate mitigation elements (BMPs) during construction, as recommended by the erosion control inspector, the potential adverse impacts from erosion hazards on the project may be mitigated. lune 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB!ld -KE07D040A4 -Projectsl200700401KE\ WP Page 12 New Transportation Center Ren/on, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report Design Recommendations III. DESIGN RECOMMEND A TIO NS 8.0 INTRODUCTION The site contains some potential soil and foundation-oriented complications with respect to compressible soils, loose granular soils susceptible to liquefaction, and moisture-and disturbance-sensitive soils. The conclusions and recommendations in this report are based upon the assumption that the foundations, floor slab, and grading construction are observed by a geotechnical engineer or engineering geologist from our firm. The proposed project is feasible from a geotechnical engineering standpoint using pile foundations for the building superstructure, and pile-supported lower floor slabs except where the owner can assume the risk of liquefaction-induced settlements during a design level (0.34g peak ground acceleration) earthquake event. Where floor slabs will be "floated," they should be constructed as a structural slab-on-grade above a minimum of 2 feet of approved structural fill compacted to 95 percent of ASTM:D 1557. Pavement support on existing fills is possible with some near-surface remedial improvements. Remediation could consist of removing the upper foot of existing fill, recompacting the resulting subgrade, and re-using the removed existing fill as structural fill, provided adequate moisture conditioning and compaction to project specifications can be achieved. Due to the possible presence of loose surficial soils, liquefaction hazards, and/or consolidation settlement, some settlement of non-pile-supported structures and paved areas, however, is anticipated, and periodic or episodic repair may be necessary. 9.0 SITE PREPARATION Site preparation of planned building and road/parking areas that will not be supported by pile foundations should include removal of all existing buildings, foundation elements, utilities, asphalt, landscaping, debris, and any other surficial deleterious material that are not part of the planned project. Additionally, any upper organic topsoil encountered should be removed and the remaining roots grubbed. Areas where loose surficial soils exist due to demolition or stripping/grubbing operations should be considered as fill to the depth of disturbance and treated as subsequently recommended for structural fill placement. The fill encountered in our explorations was generally in a loose to medium dense condition. However, the density, thickness, and rubble content of the fill across the site may be highly variable. We anticipate that any upper loose surficial fill soils, once recompacted or replaced June 14, 2007 SGBl/d-KE070040A4 -Projects\20070040\KEIWP ASSOCIATED EARTH SCIENCES, INC Page 13 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Design Recommendations with structural fill, will be adequate for support of structural slabs-on-grade, pavement and other external surfacing, such as sidewalks. However, there will be a risk of long-term damage to these surfaces including, but not limited to, rutting, yielding, cracking, etc., if any uncontrolled loose fill is not completely removed and replaced with compacted structural fill. The risk can be reduced by selective removal and replacement of the most settlement-sensitive, near-surface soils. Utilities founded above loose uncontrolled fill or fill that contains abundant rubble are also at risk of settlement and associated damage. The extent of stripping necessary in areas of the site to receive structural slabs-on-grade and external surfacing, such as sidewalks and pavement, can best be determined in the field by the geotechnical engineer or engineering geologist. We recommend proof-rolling road and parking areas with a loaded tandem-axle dump truck to identify any soft spots. If construction is to proceed during wet weather, we recommend systematic probing in place of proof-rolling to identify soft areas of the exposed subgrade. These soft areas should be overexcavated and backfilled with structural fill. Some of the on-site fill and surface soils contain a high percentage of fine-grained material, which makes them moisture-sensitive and subject to disturbance when wet. The contractor must use care during site preparation and excavation operations so that the underlying soils are not softened. If disturbance occurs, the softened soils should be removed and the area brought to grade with structural fill. If the existing pavement will not be used for access and staging areas, consideration should be given to protecting access and staging areas with an appropriate section of crushed rock or asphalt treated base (A TB). The existing pavement is in such poor condition that it may be necessary to augment the pavement with A TB if it will be used for construction access and staging. If crushed rock is considered for the access and staging areas, it should be underlain by engineering stabilization fabric to reduce the potential of fine-grained materials pumping up through the rock and turning the area to mud. The fabric will also aid in supporting construction equipment, thus reducing the amount of crushed rock required. We recommend that at least 10 inches of rock be placed over the fabric; however, due to the variable nature of the near-surface soils and differences in wheel loads, this thickness may have to be adjusted by the contractor in the field. 10.0 STRUCTURAL FILL All references to structural fill in this report refer to subgrade preparation, fill type and placement, and compaction of materials, as discussed in this section. If a percentage of June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB!ld -KE070040A4 -Projec1sl20070040\KE\ WP Page 14 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report Design Recommendations compaction is specified under another section of this report, the value given in that section should be used. After stripping, planned excavation, and any required overexcavation have been performed to the satisfaction of the geotechnical engineer, the upper 12 inches of exposed ground in areas to receive fill should be recompacted to 90 percent of the modified Proctor maximum density using ASTM:D 1557 as the standard. If the subgrade contains silty soils and too much moisture, adequate recompaction may be difficult or impossible to obtain and should probably not be attempted. In lieu of recompaction, the area to receive fill should be blanketed with washed rock or quarry spalls to act as a capillary break between the new fill and the wet subgrade. Where the exposed ground remains soft and further overexcavation is impractical, placement of an engineering stabilization fabric may be necessary to prevent contamination of the free-draining layer by silt migration from below. After recompaction of the exposed ground is tested and approved, or a free-draining rock course is laid, structural fill may be placed to attain desired grades. Structural fill is defined as non-organic soil, acceptable to the geotechnical engineer, placed in maximum 8-inch loose lifts, with each lift being compacted to 95 percent of the modified Proctor maximum density using ASTM:D 1557 as the standard. In the case of roadway and utility trench filling, tbe backfill should be placed and compacted in accordance with current local or county codes and standards. The top of the compacted fill should extend horizontally outward a minimum distance of 3 feet beyond the location of the structural slabs-on-grade or roadway edges before sloping down at an angle of 2H: 1 V. The contractor should note that any proposed fill soils must be evaluated by AESI prior to their use in fills. This would require that we have a sample of the material 72 hours in advance to perform a Proctor test and determine its field compaction standard. Soils in which the amount of fine-grained material (smaller than the No. 200 sieve) is greater than approximately 5 percent (measured on the minus No. 4 sieve size) should be considered moisture-sensitive. Use of moisture-sensitive soil in structural fills should be limited to favorable dry weather conditions. The on-site soils generally contained significant amounts of silt and are considered very moisture-sensitive. In addition, construction equipment traversing the site when the soils are wet can cause considerable disturbance. If fill is placed during wet weather or if proper compaction cannot be obtained, a select import material consisting of a clean, free-draining gravel and/or sand should be used. Free-draining fill consists of non-organic soil with the amount of fine-grained material limited to 5 percent by weight when measured on the minus No. 4 sieve fraction with at least 25 percent retained on the No. 4 sieve. A representative from our firm should inspect the stripped subgrade and be present during placement of structural fill to observe the work and perform a representative number of in- June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB/ld -KE070040A4 -Projects\200700401KE\ WP Page 15 New Transportation Center Renton, Washington Revised Subsu,face Exploration, Geologic Hazard, and Geotechnical Engineering Report Design Recommendations place density tests. In this way, the adequacy of the earthwork may be evaluated as filling progresses and any problem areas may be corrected at that time. It is important to understand that taking random compaction tests on a part-time basis will not assure uniformity or acceptable performance of a fill. As such, we are available to aid the owner in developing a suitable monitoring and testing program. 11.0 FOUNDATIONS To mitigate post-construction consolidation settlement and the effects of seismically induced liquefaction, a pile foundation system is recommended. For this project, we recommend the use of 24-inch-diameter augercast piles. Driven pipe piles are a possible foundation type, but were not suggested due to the proximity of older buildings and the high levels of vibration caused by pile-driving activities. We can provide driven pile design parameters, if requested. The following sections provide augercast pile recommendations based on assumed loading conditions and soils encountered beneath the site. It should be recognized that we have assumed relatively light-loading conditions commensurate with a two-story, wood-frame structure. The IBC recommends a maximum pile length of 30 diameters unless engineering judgment allows for modifications to this limitation based on site-specific soil conditions, building type, and pile type. For a 24-inch-diameter pile, 30D equates to a maximum pile length of 60 feet. However, the pile criteria recommended for this project utilizes piles of up to 85 feet in length. In our opinion, 85-foot-long, 24-inch-diameter piles should perform adequately in compression provided the piles will not be expected to support greater column loads than 80 kips, as we have assumed. The soil conditions encountered in our explorations will provide adequate confinement of the piles (even during a period of partial soil column liquefaction) so that "slenderness" is not considered a significant design issue. 11.1 Augercast Piles We recommend that the construction of piles be accomplished by a contractor experienced in their installation. Fill soils can have concrete, brick, wood, and other demolition waste in them, and soils of alluvial origin may have gravel lenses or large cobbles present in them. It may be necessary to have a backhoe present during pile installation to dig out obstacles and backfill the excavation prior to drilling piling. If obstacles are encountered at depths where removal with a backhoe is not feasible, it might be necessary to modify the pile layout to replace piles that cannot be completed according to the original design. Observation of pile installation by AESI is important to verify that the subsurface conditions observed at pile locations are consistent with the observations in our subsurface explorations, and consistent with assumptions made during preparation of the recommendations in this report. The City of Renton will likely require such inspections of foundation piles. June 14, 2007 ASSOCIATED EARTH SCIENCES. INC. SGB!ld -KE07D040A4 -Projectsl20070040\KE\ WP Page 16 New Transportation Center Renton, Washington Revised Subswface Exploration, Geologic Hazard, and Geotechnical Engineering Report De sign Recommendntions The augercast piles will gain support from end bearing and skin friction. Augercast piles are formed by drilling to the required depth with a continuous flight, hollow-stem auger. Fluid grout is then pumped down the hollow stem under pressure as the auger is withdrawn. Appropriately designed reinforcing steel cages are then lowered into the unset grout. A single reinforcing bar is installed for the full length of the pile for transfer of uplift loads. Since the grout is placed under pressure, actual grout volumes used are typically 15 to 50 percent greater than the theoretical volume of the pile. Actual grout volumes for piles constructed through some types of fill and peat can be much more. The pile contractor should be required to provide a pressure gauge and a calibrated pump stroke counter so that the actual grout volume for each pile can be determined. Typically, a nine-sack, minimum 4,000 pounds per square inch (psi) grout mix is used for augercast piles. Once complete, the piles would then connect to a pile cap and grade beam support system for the building foundation. Typical allowable capacities for the augercast piles are given in Table I. Development of the design capacities presented in Table I requires a minimum overall pile length of at least 20 pile diameters. To satisfy required length-to-diameter ratios, 24-inch piles are limited to 85 feet in length. Allowable design axial compressive loads may be increased by one-third for short-term wind or seismic loading. Anticipated settlement of the pile-supported foundations will generally be on the order of V2 inch. Table 1 Augercast Pile Recommendations Estimated Vertical Maximum Compressive Lateral Depth of Pile Diameter Length Capacity Capacity fixity Uplift Capacity (inches) (feet)0 ' (tons) (tons)'2J (feet)''> (tons)''J I 24 I 85 I 40 I 10 I 22 I 20 I ''' Pile length based on EB-4, EB-5, and EB-6 for bearing layer occurring between 75 and 85 feet depth. Bearing layer encountered at 35 feet in EB-3, but was not used for design. ''' Allowable lateral capacities are for fixed-headed conditions (incorporation into pile caps and grade beam system), and V, inch of deflection at the ground surface. Greater lateral capacities are possible for greater allowable deflections. "' The depth of fixity does not include the code-required 20 percent increase for reinforcing cage design. ''' Uplift capacity is based on minimum pile length of 75 feet. Piles with lateral spacing less than 6 pile diameters from another pile along the direction of force should be considered to be in the zone of influence and the lateral capacity and the reduction factors presented below should be used. If the lateral contribution of the piles is June I 4, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB!ld -K£07CXJ40A4-Projects\2CXJ700401KE\WP Page 17 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report Design Recommendations more critical to the practical design of the structure, we can provide a comprehensive lateral pile analysis. Such an analysis would present lateral pile capacities taking into account the interaction between piles. Based on the loose conditions of the soils through which the augercast piles are to be excavated, care should be taken in construction planning to allow grout time to set prior to drilling adjacent piles. Typically, 24 hours of set time is recommended for piles closer than 3 diameters or 10 feet, whichever is greater. The 24 hours can be reduced for adjacent piles drilled on different workdays. 11.2 Group Effects Where piles are installed in groups and subject to lateral loading, reductions in lateral capacity to account for group effects should be included in design. The effects of group performance should be considered where piles are spaced closer than 6 pile diameters center-to-center and are aligned in the direction of loading. Piles should not be spaced closer than 3 pile diameters center-to-center to achieve full vertical and uplift capacity. If piles are staggered in the x and y directions a minimum of 3 pile diameters, there is no reduction in lateral loading. For the determination of individual capacities for load application parallel to the line of spacing, the following spacing and reduction factors presented in Table 2 should apply. The last pile in a row can be assumed to develop the full lateral capacity. Table 2 Lateral Reduction Factors I Pile Spacing I Reduction Factor I 6 diameters 1.0 5 diameters 0.8 4 diameters 0.6 3 diameters 0.4 11.3 Passive Resistance and Friction Factors Lateral loads can be resisted by friction between the pile caps and grade beams and the existing fill soils or structural fill, or by passive earth pressure acting on the buried portions of these elements. The foundations must be backfilled with structural fill and compacted to at least 95 percent of the maximum dry density to achieve the passive resistance provided below. We recommend the following design parameters: June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGBl/d-KE070040A4 -Projects\20070040\KEIWP Page 18 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnica/ Engineering Report Design Recommendations • Passive equivalent fluid = 200 pounds per cubic foot (pct) • Coefficient of friction = 0.30 The above values are allowable and include a safety factor of at least 1.5. 12.0 FLOOR SUPPORT As discussed earlier in this report, existing site soils are considered to be settlement-prone, and we therefore recommend that floor slabs be designed as "floating" slabs-on-grade or be structurally supported on pile foundations. Where potentially large-scale liquefaction-induced settlement can be tolerated, site soils can be used to support slab-on-grade floors, sidewalks, or other similar structures contingent upon adequate remedial preparation and understanding of uncertainties in settlement performance. Repairs to damaged "floating" slabs-on-grade should be expected following significant seismic shaking. Slabs or pavement to be supported on grade should be supported on a 2-foot-thick structural fill mat. All fill beneath slabs or pavement must be compacted to at least 95 percent of ASTM:D 1557. The floor slabs should be cast atop a minimum of 4 inches of clean washed crushed rock or pea gravel to act as a capillary break. Areas of subgrade that are disturbed (loosened) during construction should be compacted to a non-yielding condition prior to placement of capillary break material. It should also be protected from dampness by an impervious moisture barrier at least 10 mils thick. The impervious barrier should be placed between the capillary break material and the concrete slab. 13.0 DRAINAGE CONSIDERATIONS All exterior grade beams should be provided with a drain at least 12 inches below the base of the adjacent interior slab elevation. Drains should consist of rigid, perforated, polyvinyl chloride (PVC) pipe surrounded by washed pea gravel. The drains should be constructed with sufficient gradient to allow gravity discharge away from the building. Roof and surface runoff should not discharge into the footing drain system, but should be handled by a separate, rigid, tightline drain. In planning, exterior grades adjacent to walls should be sloped downward away from the structure to achieve surface drainage. 14.0 PAVEMENT RECOMMENDATIONS The majority of the parking and access areas are planned for those portions of the site underlain by fill materials overlying loose/soft soils. Considering the poor condition of the June 14, 2007 AssqcJATED EARTH SCIENCES, INC. SGB/ld -KE070040A4 -Projectsl20070040\KEIWP Page 19 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnica/ Engineering Report Design Recommendations existing pavement and constant bus traffic, some remedial measures may be necessary for support of pavement, Ideally, pavement sub grades would be prepared by selectively removing, replacing, and recompacting the upper 1 to 2 feet of site soils to provide a uniform thickness of compacted structural fill to support bus drive and parking lot pavement sections. The upper existing soils are, however, moisture-sensitive and contain scattered organics and rubble. In addition, site work may occur during the wetter winter months or during wet site conditions. Therefore, it is recommended to assume that some of the site soils may not be reused as structural fill and may need to be replaced with imported select soils. During the winter months, a SO-percent replacement assumption is reasonable, while during the drier summer months, a 25-percent replacement assumption is reasonable. The use of unit prices for removal and replacement of unsuitable soils is recommended. Alternatively, to reduce the depth of unsuitable soil removal, an engineering stabilization fabric or geogrid reinforcement could be placed over the stripped subgrade prior to filling. The addition of an engineering stabilization fabric or geogrid permits heavier traffic over soft subgrade and increases the service life of the system. The fabric acts as a separation barrier between relatively fine-grained surficial materials on the site and the load-distributing aggregate (sand or crushed rock). A separator reduces the loss of costly aggregate material into the subgrade and prevents the upward pumping of contaminating silt into the aggregate. The use of fabric or geogrid would be a field decision based on actual conditions encountered. A unit price for separation fabric is recommended. Upon construction of the 2-foot structural fill (reworked site soils or imported fill), a pavement section consisting of 4 inches of asphalt concrete pavement (ACP) underlain by 2 inches of 5/s-inch crushed surfacing top course and 6 inches of 1 \/,~inch crushed surfacing base course is recommended for heavy (bus) traffic areas. For light-duty car parking areas, a pavement section consisting of 3 inches of ACP over 4 inches of crushed rock surfacing over a properly prepared subgrade can be used. The crushed rock courses must be compacted to 95 percent of maximum density. Given the potentially variable in-place density of the existing fill sub grade, some settlement of paved areas should be anticipated unless the existing fill is entirely removed and replaced with structural fill. 15.0 PROJECT DESIGN AND CONSTRUCTION MONITORING At the time of this report, site grading, structural plans, and construction methods have not been completely finalized. We are available to provide additional geotechnical consultation as the project design develops and possibly changes from that upon which this report is based. June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB!ld -KE070040A4 Projects\2007004(}\KE\WP Page 20 New Transportation Center Renton, Washington Revised Subswface Exploration, Geologic Hawrd, and Geotechnical Engineering Report Design Recommendations We recommend that AES! perform a geotechnical review of the plans prior to final design completion. In this way, our earthwork and foundation recommendations may be properly interpreted and implemented in the design. We are also available to provide geotechnical engineering and monitoring services during construction. The integrity of the pile foundation system depends on proper site preparation and construction procedures. In addition, engineering decisions may have to be made in the field in the event that variations in subsurface conditions become apparent. Construction monitoring services are not part of this current scope of work. If these services are desired, please let us know, and we will prepare a cost proposal. We have enjoyed working with you on this study and are confident that these recommendations will aid in the successful completion of your project. If you should have any questions or require further assistance, please do not hesitate to call. Sincerely, ASSOCIATED EARTH SCIENCES, INC. Kirkland, Washington ~~~ Susan G. Beckham, P.E. Senior Project Engineer Attachments: Figure 1: Figure 2: Figures 3 & 4: Appendix: June 14, 2007 SGB/id-KE07004()A4 -Projectsl20070040\KE\WP Vicinity Map Site and Exploration Plan Liquefaction Analysis Exploration Logs Laboratory Testing Results Kurt D. Merriman, P.E. Principal Engineer ASSOCIATED EARTH SCIENCES, INC. Page 21 jj f 5 ! j C t, , ~ ' ~ ,Cl' • , ',.' -------------'--1-1·-·-.. --__ -_ . '.:_ . .::'..1 1 z 1 , :; . ..I.. l/) 'o' •• , ', ·r ,. C ,,;k r,," 1:T I .I 1' ----,------~~---, .. -~ 1Wf1l.;l7,1o. t,rl~\ lt, ! 1r. :·.,, ,,. ~· •" ' ' v, -....._ ---~r-.-. r~ --·-~"' ~~·:,if; i,i: i· ·-· ,, .. ,,., i t 11 , ,I I , •• r <:.; ,.,, !', In i,· \ ~,"'t· ·,.';';1 ·-,: ... , I .::.~· -., -~-1 . 11 --I?: .... "':', I"'" , 1 ~ ', -..ri",: }~\r-L.,· .. ~ ···~-It -: -.:.l .... :_ ;;-'"'I : r ..,,/--, .. 'lJ()"~_..,.,~., .11 .·LJif;· b>:c ,. 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Ii ,, :!! 1,1 ,11 !)\ \ I "' ' / !! / ,1i I !I 1'Ji1 i'1 '11 l'i '\ !\ ii \,1 111 " I \\ ii I \\ 'I 1 ,,1 Ii \ \I 11' 1, 1,\: I 1il \, lli I 11 \ !) \;, i'" ,1 \ 111 ! j i i ,I 1:1 ;i 1:, 11! I I . 11· I . ' ~I <: ~ <( i5 C et:: ~ I """' 'li_ SB ;-~7;'~d ~ 0 ' ~ =&.:m~ ~ ~ I-r-;;s - "Cl =5;! a """ ~---\f: ~-.::~ """' ~ --"'"7'11:Z'C ~1Y jjjnj i~ 6 liiii.f.iUJA """' .... ! N. 4TH STREET i j Reference: PACE & J Associated Earth Sciences, Inc. SITE AND EXPLORATION PLAN FIGUREZ i m .ii [W i.i ~ NEWTRANSPORTAIONCENTER DATE3/07 I ~ bE ~ ~ L.&fl RENTON, WASHINGTON PROJECT NO. KE070040A B--==--==--==--==--=-=--------------------------- E 8 LIQUEFACTION ANALYSIS New Renton Transportation Center Hole No.=EB-3 Water Depth=l ft Shear Stress Ratio Factor of Safety Settlement /ff) O 2 0 1 5 0/in.) 50 o ,r,-r:,~---''.--:-r-:-rJ::::I=I , ,, " ,, , / 10 20 30 -40 fs=1 CRR~ CSR - Shaded Zone has Liquefaction Potential 50 60 ' I I I I I I I ( J i I I I I I Wet~ Dry- S=10.10in_ Soil Description III!t!!I Silty Sand Fill 1111111 Silt (Alluvium) Silty Sand ....... ::;:i§~;'. ....... -~~{~{ Well graded Sand f~Jf;j Fine to medium Sand Silty Sand . ' '' Silt Silt and peat Silty Sand (Pre-Vashon) ~ 70 CivilTech Corporation KE070040A Magnitude=l Acce/eration=0.34g Raw Unit Fines SPTWeight % 30 130 5 5 90 60 4 95 45 15 110 4 9 105 5 4 95 49 3 85 70 9 100 82 44 135 20 39 132 21 35 131 12 Figure 3 I LIQUEFACTION ANALYSIS New Renton Transportation Center Hole No.=EB-5 & EB-4* Water Depth=7 ft Shear Stress Ratio Factor of Safety Settlement (ff) 0 2 01 5 O(in) 50 0 ~~T::"T:"Y-TCT:=i::::::r:=:r=:j , , , I I I I I I I I I I I I I I I I / I 15 \ I ! I I ( I 30 I 45 I Soil Description Silty Sand Fill Silt (Alluvium Silty Sand Sand Magnitude=? Acceleration=0.34g Raw Unit Fines I SPTWewht % I 30 13 5 8 98 60 8 98 45 2 90 4 2 90 4 11 1i5s fo 3 85 70 0 80 70 3 85 70 5 87 60 26 120 26 I 11 1 DO 50 ii.ii: ~=~~-----------! Silty Sand 60 75 90 fs CRR-CSR - Shaded Zone has Liquefaction Parentiaf 105 CivilTech Corporation i ! ! ' ! ' ' r I I ' I I I Wet-Dry- s= 28.67 in. KE070040A 10 105 30 Sand 27 121 5 Silty Sand 14 105 40 Silt 10 110 12 Sand 34 130 4 31 125 50 Silty Sand 12 105 30 J<" 66 135 5 ¥ Silt 34 120 55->i' Figure 4 - APPENDIX ID > ID (I) 0 0 N 0 z m ID m m "' 0. i" 0 2 J, *' 0 "' -"' ·o U) " ID C ·~ "' " C u: ~ -g §: LC C • ; :§ ~ • 0 • 0 Well-graded gravel and GW gravel with sand, little to no fines GP Poorly-graded gravel and gravel with sand, little to no fines Silty gravel and silty GM gravel with sand Terms Describing Relative Density and Consistency Coarse- Grained Soils Fine- Grained Soils Density SPT(21 blows/foot Very Loose O to 4 Loose 4 to 10 Medium Dense Dense Very Dense Consistency Very Soft Soft 10 to 30 30 to 50 >50 SPT(21 blows/foot Oto 2 2 to 4 4 to B Test Symbols G = Grain Size M = Moisture Content A = Atterberg Limits C = Chemical DD = Ory Density K = Permeability .... Q.) i.i: ~~*~~*-+----------~ Medium Stiff Stiff 8 to 15 15to30 "' ,., C 0 ·~ ~~ )/) ~ if :::::::::: ~ a) #. "'> "' 8 .~ \Al _.., Clayey gravel and GC clayey gravel with sand Well-graded sand and sw sand with gravel, little to no fines SP Poorly-graded sand and sand with gravel, little to no fines Very Stiff Hard >30 Descriptive Term Boulders Cobbles Gravel Coarse Gravel Fine Gravel Sand Component Definitions Size Range and Sieve Number Larger than 12" 3" to 12" 3" to No 4 (4.75 mm) 3' to 3/4" 3/4" to No. 4 (4.75 mm) 0 ... ID • o~~h--+-+----------~ 2 m Silty sand and Coarse Sand Medium Sand Flne Sand No. 4 (4.75 mm) to No. 200 (0.075 mm) No. 4 (4.75 mm) to No. 10 (2.00 mm) 0 ~ ;:;;-SM ~ ~'1) silty sand with ";J!. a.. ~ gravel Silt and Clay No. 10 (2.00 mm) to No. 40 (0.425 mm) No. 40 (0.425 mm) to No. 200 (0.075 mm) Smaller than No 200 {0.075 mm) Clayey sand and ~ ~\L,J'.!-f-,/.1--+----------~ f-,-~--------------------------1 (3 ) Estimated Percentage sc clayey sand with gravel Component --+-----------! Percentage by Weight Silt, sandy silt, gravelly silt, ML silt with sand or gravel CL Clay of low to medium plasticity; silty, sandy, or gravelly clay, lean clay Trace Few Little With <5 5 to 10 15to25 -Non-primary coarse constituents: > 15% -Fines content between 5% and 15% Moisture Content Dry -Absence of moisture, dusty, dry to the touch Slightly Moist -Perceptible moisture Moist -Damp but no visible water Very Moist -Water visible but not free draining Wet -Visible free water, usually from below water table Organic clay or silt of low OL plasticity Symbols Blows/6" or Sampler portion of 6" Elastic silt, clayey silt, silt Type "" / 2.0" OD "" " Sampler Type MH with micaceous or diatomaceous fine sand or Split-Spoon : Sampler 3.0" OD Split-Spoon Sampler IWW.IJ----1-"s"'ilt~---------, (SPT) Clay of high plasticity, 3.25" 00 Split-Spoon Ring Sampler sandy or gravelly clay, fat Bulk sample clay with sand or gravel • 3.0" OD Thin-Wall Tube Sampler (including Shelby tube) Cement grout surface seal Ben!onite seal Filter pack with . blank casing ·.· section Screened casing or Hydro\ip ~-+-------------! Grab Sample · · with filter pack End cap o Portion not recovered (1l Percentage by dry weight r2i (SPn Standard Penetration Test l---+-----------j (ASTM 0-1586) Peat, muck and other r31 In General Accordance with Organic clay or silt of OH medium to high plasticity PT highly organic soils Standard Practice for Description and Identification of Soils (ASTM 0-2488) (4l Depth of ground water :J. ATD = At time of drilling '5/.. Static water level (date) !5l Combined USCS symbols used for fines between 5% and 15% 1 ;-; Classifications of soils in this report are based on visual field and/or laboratory observations, which include density/consistency, moisture condition, grain size, and J plasticity estimates and should not be construed to imply field or laboratory testing unless presented herein. Visual-manual and/or laboratory classification cc (5 methods of ASTM D-2487 and 0-2488 were used as an identification guide for the Unified Soil Classification System. 5===================================================== i Associated Earth Sciences, Inc. E' (lll~liJBIIJJ EXPLORATION LOG KEY FIGURE A1 "----------------------------------------------------- Associated Earth Sciences, Inc. Exoloration Lon ~ [i] ~ ~ m Project Number I Exploration Number I Sheet . -KE070040A EB-1 1 of 1 Project Name l\le'l>' Iransi,ortation Center Ground Surface Elevation (ft) Location Renton WA Datum t.irl\ Driller/Equipment 8Qrtech Track Rig Date Start/Finish 2121 IOZ 2121/0Z Hammer Weight/Drop 140# / 30" Hole Diameter (in) 4iacbeS C ,i • g ~ -~O 0 > a ;;; ID =·ii ID <O Blows/Foot ,! £.c _.., " £ 0. ~[ ID-~ ~ C. s E SE" 2 .Q ii; ID T m "'"' £ Cl if) 0 ~ (D 5 DESCRIPTION 0 10 20 30 40 Fill 2 inches asphalt, 2 inches base rock Loose lo medium dense, moist, black, silty fine to medium SAND, with gravel S-1 . Quaternary Alluvium 5 .. , 4 Medium stiff, moist, dark gray, clayey SILT, with organics. 4 -5 Very soft, very moist. dark gray, sandy SILT, with very thin fine sand S-2 1 .. , seams. 1 1 '!' -10 Very soft, saturated, dark gray, sandy SILT, with peat stringers and wood. S-3 11, [J.1112' -·----··--·-------- Bottom of exploration boring at 11 5 feet Ground water at 9 feet -15 - -20 -25 -30 I I -35 Sampler Type (ST): [D 2" OD Split Spoon Sampler {SPT) D No Recovery M • Moisture Logged by: SGB [I] 3" OD Split Spoon Sampler (D & M) I] Ring Sample '5l-Water Level () Approved by: lrB Grab Sample 121 Shelby Tube Sample.!. Water Level at time of drilling (ATD) Associated Earth Sciences, Inc. Exoloration Loa ~ [I] l~ftol ~ ~ Project Number I Exploration Number I Sheet ' -KE070040A EB-2 1 of 1 Project Name N11w Iraosr,ortation Centec Ground Surface Elevation (ft) Location R11o!Qn WA Datum .,,. Driller/Equipment Bortech T[;,Ck Rig Date Start/Finish 21211012121101 Hammer WeighVDrop 140# / 30" Hole Diameter (in) A.incbe· g o- C ~= 2 ID -o .Q ID !f' ID " ~ .0 =ii> Blows/Foot ID £ ~ ~E _J ID >-ID-~ ~ ~ s E ~ >-s:E .!B .Q '" ID T m CJ"' 0 "' 0 ::1 00 ~ DESCRIPTION u 10 20 30 40 0 Fill 2 inches asphalt concrete, 2 inches base rock. Loose to medium dense, moist, dark brown, silty fine to medium SAND, with gravel and asphalt. S-1 Quaternary Alluvium ------6 .. , 2 Medium stiff, moist, brown and gray mottled, SILT, with fine sand, few 3 organics 5 ~ S-2 2 .. ~ Verymo.is.t.sed-brown, fine SAND. feYLsjfi.,_ ___ ,,.___ -.~~---·-··-· --~-5 ' Bottom of exploration boring at 6 5 feet No ground water ~ 10 ~ 15 -20 -25 -30 -35 Sampler Type (ST): []] 2" OD Split Spoon Sampler (SPT) 0 No Recovery M -Moisture Logged by: SGB []] 3" OD Split Spoon Sampler {D & M) I] Ring Sample Sl Water Level {) Approved by: ~ Grab Sample (ZJ Shelby Tube Sample!. Water Level at time of drilling (ATD) Associated Earth Sciences, Inc. Exnloration Loa ---- Project Number I I ~ CB ~ ~ ~ Exploration Number Sheet -KE070040A EB-3 1 of 2 . Project Name New Transl)ortation Cente[ Ground Surface Elevation (ft) Location Renton WA Datum "" Driller/Equipment Bortech In;ick Rig Date Start/Finish 2121/0Z,2121/0Z Hammer WeighUDrop 140# I ;JO" Hole Diameter (in) 4iocbes g C .. ~ ~ u-.2 > ' -0 " se .,, .c"' =m _, 00 Blows/Foot " .c "-~[ w-~ ~ I- ci s E SE .s _Q :. " T m (!) (I) a (I) 0 ;: a, .c DESCRIPTION u 5 10 20 30 40 Gravel surfacing/no heave observed or reported Fill Medium dense, molst, black, silty fine to medium SAND, with gravel and asphalt (SM). I ' S-1 Quaterna1 Alluvium 2 ... , Very moist, brown mottled, sandy SIL , with fine sand seams to 1 inch ' thick (ML). -5 I Very moist, brown mottled, silly very fine SAND, stratified, with lenses of S-2 ' .... silt and clean sand (SM), 1 ' -10 I Very moist, brown, clean fine to coarse SAND, with gravel, trace silt, 50% S-3 ' ... , recovery (SW) :,: 7 8 -15 Water added after 15-foot sample_ S·4 Saturated, fine to medium SAND, with lenses of fine gravel to 6 inches 5 thick, trace sill (SP). 5 ' 9 4 -20 +--Saturated,Qiay-;-sTitYsANDto-SfLT. With fine'sind and peat arld1er15es-of -· S-5 ' ... fine sand to 1 inch thick (SM/ML) 2 2 -25 Wet, gray, SILT, with peat stringers and fine sand (ML). S-6 ' ... 3 2 1 : -30 Wet, gray, SILT, and brown PEAT (MUPT) S-7 3 4 • 9 5 -35 S-8 Gravels reported by driller at 35 feet. 17 .... Saturated, brown, silty fine to coarse SAND, with gravel, trace organics, 23 50% recovery (SM) 21 I Sampler Type (ST). OJ 2" OD Split Spoon Sampler (SPT) D No Recovery M -Moisture Logged by: SGB []] 3~ OD Split Spoon Sampler (D & M) I] Ring Sample '¥-Water Lever O Approved by: IQJ Grab Sample 0 Shelby Tube Sample l'.. Water Level at time of drilling (ATD) " 0 m in w < Associated Earth Sciences, Inc. Exnloration Loa l~I w ~ ~ m Project Number I Exploration Number I Sheet . KE070040A EB-3 2 of 2 - Project Name New Tr<1nsportation Csioter Ground Surface Elevation (ft) Location Renton WA Datum ..,, Dril1er/Equipment Bo[(sich Trac~ Big Date StartlFinish 2121 IOZ 2121 IOZ Hammer WeighVDrop 140#/30" Hole Diameter (in) 4iocbes g C i= m o-0 ID ·-0 =i; ID Sf? Blows/Foot ~.o ~ a. ~~ _, 00 ID--~ 0. s E ~ @" 2 .Q ID T ~ C)"' 0 "' 0 i " DESCRIPTION () 10 20 30 40 S-9 Saturated, brown, fine to medium silty SAND, with gravel, 50% recovery 13 ' 39 (SM). 19 20 -45 Same as above. 10 S-10 14 ... , f---·--------·------------21 Bottom of exploration boring at 46.5 feet Ground water al 11 feet ATD -50 -55 -60 ~ 65 I -70 -75 Sampler Type (ST): [] 2" OD Split Spoon Sampler {SPT) D No Recovery M -Moisture Logged by: SGB [] 3" OD Split Spoon Sampler (D & M) I] Ring Sample ';!. Water Level () Approved by: IQ] Grab Sample l2J Shelby Tube Sample!. Water Level at time of drilling (ATD) 00 -;;; ~ ~ ~ i5 Associated Earth Sciences, Inc. Exnloration Loa 1--~~~~--~----'=c~'-'--"'-"-":C,..,.,==-~---~--c------l Project Number I Exploration Number I Sheet KE070040A EB-4 1 of 3 Project Name Location Driller/Equipment Hammer WeighVDrop -5 S-1 -10 S-2 ~ 15 S-3 ~ 20 S-4 -25 S-5 -30 S-6 -35 S-7 ~ ~ New Transportation Center Renton WA Cascade/CME 85 140# / 30" DESCRIPTION _ Asphalt ___________ FiTi __________ ·-____ _ Crushed rock and pit run, sand and gravel. ------Quaternary Alluvium Moist, light o!lve-gray, weakly stratified, sandy SILT and silly fine SANO (MUSM) Moist to wet, light olive-gray, stratified, silty fine SAND and fine to medium SAND, trace silt, trace thin laminae of organics (SM/SP) Same as above Wet, light gray, non-stratified, fine to coarse SAND, trace to few silt (SW/SM) Wet, light gray and light brown, interbedded PEAT and fine to coarse SAND. trace silt. trace organics (PT/SW), Wet, light olive-gray, stratified, clayey SILT (ML) Wet, light olive-gray and light brown, interbedded silty CLAY, PEAT, and fine to coarse SANO, trace silt, and organics (CUPT/SW) Ground Surface Elevation (fl) Datum .__b111.B' "-------- Date StarUFinish ?!?7/07 2127/Ql Hole Diameter (in) ~-~B~inwcwbwe~' s~----- Blows/Foot 10 20 30 40 1 2 ... 4 2 3 3 ... , 3 a 12 16 5 7 10 0 1 .. , 2 2 4 7 ... a .. 7 .,, ~1--~S~a""'m-pLle-r~T~yLp_e~(S~T",)---------------------------"---'-L-L-_-'----'----'----'---~~'---1 s ITl D ~ 2" OD Split Spoon Sampler (SPT) No Recovery M -Moisture ~ OJ 3" OD Split Spoon Sampler (D & M) I] Ring Sample ";l_ Water Level O Logged by: JDC Approved by: ~ ~ Grab Sample l2J Shelby Tube Sample.?-Water Level at time of drilling (ATD) ~'---------------------------------------------------__J Associated Earth Sciences, Inc. Exoloration Loa ~ [}J ~ u ~ Project Number I Exploration Number I Sheet . . KE070040A EB-4 2 of 3 Project Name New Transportation C,m!er Ground Surface Elevation (ft) Location Benton WA Datum "'" Driller/Equipment Ca~cade/CME 85 Date Start/Finish 2/2Z/OZ 21:21/0Z Hammer Weight/Drop 140# / 30" Hole Diameter (in) ~Siocbes g C <i, 2 "' o-.2 >' "' -0 ID ,e "' ~,, =iii'. Blows/Foot ID ~ a. a}E _, "' I- 1i s E ~} ~ ~ ~ ~ ~ ID O ID T "' "'U) ~iii ~ 0 U) 0 i5 DESCRIPTION Ll 1D 20 40 30 S-8 Wet, light olive-gray, non-stratified, silty fine SAND (SM). 7 -"21 12 9 I-45 Same as above S-9 0 5 ~,o 5 -50 Wet, light olive-gray and light brown, interbedded PEAT and silty CLAY S-10 1 (PT/CL). 5 10 5 1-55 Wet, light olive-gray, interbedded, clayey SILT and silty fine SAND S-11 a .. , (MUSM) ,o 15 -60 Wet, light olive-gray, sandy Sll T (ML) S-12 7 -"21 10 11 1-65 Blow count not SPT: 300 pound -down hole hammer and 2-inch spoon. S-13 3 .. ,. 1,.11 Wet, light olive-gray and light brown, stratified, clayey SILT, few peat in 1-5 to 2-inch stringers (MUPT/Ml) 6 ·Equivalent SPT -70 Blow count not SPT: 300 pound -down hole hammer and 2-inch spoon. S-14 7 ' ,. "1• Wet, light olive-gray, weakly stratified, silty fine SAND {SM}. a 10 --~~-- I -75 Wet, light olive-gray, weakly stratified, silty fine to medium SAND, trace S-15 11 .. 7 scattered peaty organics (SM). 18 19 Sampler Type (SD: rn 2" OD Split Spoon Sampler (SPT) 0 No Recovery M -Moisture Logged by: JOG rn 3" OD Split Spoon Sampler (D & M) I] Ring Sample Si'. Water Level {) Approved by: ~ Grab Sample [2J Shelby Tube Sample~ Water Level at lime of drilling (ATD) Associated Earth Sciences, Inc. Exoloration Loa I~ w ~ ~ m Project Number I Exploration Number I Sheet . ' KE070040A EB-4 3 of 3 Project Name New TransportatiQn C~nter Ground Surtace Elevation (ft) Location Renton WA Datum 11.1,,. Driller/Equipment Cascade/CME 85 Date Start/Finish 212ZIOZ 212ZIOZ Hammer Weight/Drop 140# / 30" Hole Diameter (in) ...::::BJncbPs C "ij; 00 g 00 f!Q 0 > a ;; -" :::;:~ w <D Blows/Foot ,"' ~ .c ..J .; ~ ~ g-E .,_ " ~ Q. s E "" ;;: E° J!l 0 :,; w T ro ""' ~ 00 5 D (/) 0 DESCRIPTION 0 D 10 20 30 40 S-16 Same as above. 13 14 .. 33 19 -85 Wet, light olive-gray, weakly stratified, silty fine to medium SAND (SM). S-17 I .. ,, 2 10 -90 Wet to moist. light olive-gray, stratified, fine to medium SAND, few silt, S-18 10 trace organics in thin laminae (SM). 33 '" 33 -95 Wet, light olive-gray, stratified, sandy SILT (ML) S-19 16 .. ,, 17 ----------~-~------------17 Bottom of exploration boring at 9S 5 feet Ground waler at 10 feel ~100 -105 -110 I I -115 Sampler Type (SD: [I] 2" OD Split Spoon Sampler (SPT) D No Recovery M -Moisture Logged by: JDC [I] 3" OD Split Spoon Sampler (D & M) I] Ring Sample 'SJ. Water Level O Approved by: rJl Grab Sample IZl Shelby Tube Sample~ Water Level at time of drilling {ATD) Associated Earth Sdences1 Inc. Exnloration Loa ~ [}J [§i] ~ m Project Number I Exploration Number I Sheet . -KE070040A EB-5 1 of 3 Project Name New TranspQrtation Center Ground Surface Elevation (ft) Location Ri;oton WA Datum ..!>I'" Driller/Equipment Bocti;gh Track Rig Date Start/Finish 2121 /OZ 2/2 J /OZ Hammer WeighVDrop 14111t I ~()" Hole Diameter (in) 4 inches g C ~-B ~ u-.Q ~ • -0 =iii • !£ Blows/Foot ~ ~ a. ~ .n ~ ~ 15. s E ~[ •o. ~ ~ ;,; SE 2 .Q • T ~ (9 U) 0 ,1: a, £ 0 U) DESCRIPTION () 10 20 30 40 0 FIii Exposed aggregate asphalt. Brown, SAND and GRAVEL, few silt. ----------------Quaternary Alluvium S-1 6 .. , Medium stiff, moist, gray and brown, SILT, trace organics and loose, silty 4 SAND. with gravel (MUSM) 4 -5 -No sample. S-2 - S-3 Soft, wet, dark brown and gray, SILT (ML), with peat lenses to 2 inches 2 .. , -10 -thick. --·-.,---------------'!' 1 Wet. gray, silty fine SAND (SM). 1 >-15 S-4 Saturated, gray, fine to coarse SAND, with silt, little gravel (SP) • l,i.41 -20 20 Stif( saturated, gray, SILT (M[y ·------------·----------· 21 S-5 Soft, saturated, gray, SILT, with fine sand (ML). 0 .. , -25 0 . Medium stiff, saturated, PEAT (PT). 3 S-6 Very soft. saturated, gray, SILT, with fine sand and organics (ML) 0 -30 0 0 0 S-7 Very soft, saturated, gray, SILT (ML). with fine sand and peat stringers. 0 .. , -35 0 Medium stiff, saturated, dark brown, PEAT (PT). 3 I I ~-R lnterbedded medium stiff, saturated, gray, SILT, with fine sand and woody 1 .. , I Sampler Type (ST): [I} 2" OD Split Spoon Sampler (SPT} D No Recovery M -Moisture Logged by: SGB [lJ 3" OD Split Spoon Sampler (D & M) I] Ring Sample sz Water Level () Approved by: ~ Grab Sample 0 Shelby Tube Sample:?. Water Level at time of drilling (ATD) Associated Earth Sciences, Inc. Exnloration Loa ~ w ~ ~ m Project Number 1 Exploration Number I Sheet -KE070040A EB-5 2 of 3 Project Name New Transgoctation Center Ground Surlace Elevation (fl) location Renton WI', Datum J'J'" Driller/Equipment Bortech Track Rig Date Start/Finish 212liOZ 2/21/0Z Hammer Weight/Drop 140# / 30" Hole Diameter (in) 4 inches -j;; g C m ID o-0 >' -o m ,e ~ ~D ID~ Blows/Foot m ~ ~ ~E -' ID I- a_ s E ;;:~ ~ ~ ~ >-"'0 :;; m T m Cl U) ! co ~ 0 U) 0 5 DESCRIPTION 0 10 20 30 40 PEAT (MUPT) 2 3 -45 S-9 Saturated, gray, fine to medium SAND, with organics, and Sil T stringers, stratified (SP). 7 .. , 12 14 S-10 Gray and black interbedded Sll T (laminated with very thin peal stringers). 5 .. ,, -50 5 Silty SAND, with organics and PEAT lenses to 3 inches thick (MUSM/PT). 6 S-11 Saturated, brown, silty fine to medium SAND, with peat lenses and wood 6 -55 (SM) 5 ~10 5 __ .s_aiurate_d ... _gray, SILT with fine sand (M_I,.).,_ _________ ------ S-12 Saturated, gray, fine to medium SAND, with silt {SP). 0 .. 7 r 60 12 15 S-13 5 .. 14 r 65 -Tnfe"ibedded, saturated, gray, silty fine SANb alld sandy SILT, with peat -6 stringers, stratified (SM/Ml). 8 S-14 Saturated, gray, fine to medium SAND, with silt, stratified (SP)-0 70 5 10 Gray, Sil T, with peat seams to 3 mm thick (ML). 5 Saturated, gray, fine to medium SAND, S1ff grading to fine SANO, with silt, S-15 trace organics, weak slratification {SP). 9 .. " -75 16 18 T S-1S Saturated, gray, fine to medium SAND, weakly stratified grading to SILT, 13 • Sampler Type (ST): [D 2" OD Split Spoon Sampler {SPT) 0 No Recovery M -Mois1ure Logged by: SGB [D 3" OD Split Spoon Sampler (0 & M) I] Ring Sample 2 Water Level () Approved by: ~ Grab Sample [2] Shelby Tube Sample:? Water level at time of drilling (ATD) Associated Earth Sciences, Inc. Exoloration Loa ~ [B ~ ~ m Project Number I Exploration Number I Sheet ' KE070040A EB-5 3 of 3 ' Project Name New Transr,ortation Center Ground Surface Elevation (ft) Location Renton WA Datum ~1/\ Driller/Equipment Bortech Track Rig Date Start/Finish 212 J/O:Z,212 J /OZ Hammer Weight/Drop 140#/ 30" Hole Diameter (in) 4iocbes g C ~: !!l 0 u-0 0 -0 "' <O .'! ~,, =~ -' ;;; Blows/Foot "' ~ 0. o.E "'<i ~ ~ f- 0. s E ~~ S: E "'0 " "' T ~ C9 <I) ~ CD ~ 0 <I) 0 5 DESCRIPTION CJ 10 20 30 40 J_ __ with fine sand _($P/ML). -14 -~------17 Bot1om of exploration boring at 80 5 feel Ground water at 10 feel. No heave -85 -90 -95 t-100 -105 -110 -115 Sampler Type (ST) [I] 2" OD Split Spoon Sampler {SPT) D No Recovery M -Moisture Logged by: SGB [I] 3" OD Split Spoon Sampler (D & M) I] Ring Sample 'l-Water Level O Approved by: ~ Grab Sample [J Shelby Tube Sample.!. Water Level at time of drilling {ATD) Associated Earth Sciences, Inc. Exnloration Lo~ ~ [I] ~ ~ [l;E] Project Number 1 Exploration Number I Sheet . KE070040A EB-6 1 of 3 Project Name New Transgortation Center Ground Surface Elevation (ft) Location Reoton WA Datum . ". Driller/Equipment Bo[!ech Track Rig Date Start/finish 2121/0Z 212J/07 Hammer WeighUDrop 140# / 30" Hole Diameter {in) 4iocbes g C ~: 2 • u-0 w ·-0 =~ " <O .., ~.D -' .;; Blows/Foot " ~ 0. ~[ " --~ f- Q. s E s:~ " 0 ;;; " T • Cl"' ~ca ~ Cl "' 0 i5 DESCRIPTION () 10 20 30 40 Fill Exposed aggregate asphalt/gravel surfacing_ Moist. silty SAND, cuttings, with gravel. ·-·--·---Quaternary Alluvium S-1 Soft, moist, brown, sandy SILT. with thin fine sand seams (ML). 0 ... -5 2 2 S-2 Saturated, red-brown, fine SAND. with silt and gravel (SP) 3 A14 -10 "' 5 9 ---------------------------------- S-3 Very soft, saturated, gray, clayey SILT, few gravel and grades to sandy silt 0 -15 at 15 feet {ML-MH). o •o 0 -20 S-4 Saturated, gray, silty fine SAND, with gravel, weakly stratified (SM) 0 7 • 19 12 -. ----· S-5 Soft, interbedded. saturated. gray, S!LT and fine to medium SAND, with silt 0 -25 (SM/SP) o •o 0 S-6 Saturated, gray, medium to coarse SAND, few gravel, trace silt (SP) 1 -30 non-stratified. ' ' .. , Wet, gray and brown, SILT, with peat stringers (stratified) (ML) 5 S-7 Saturated, gray, silty medium to coarse SAND grading to gray and brown, 0 .. , -35 interbedded SILT, with fine sand and PEAT {SM/PT/ML) 1 3 -·--------------------------------- S:-8 Saturated, gray, fine to coarse SAND, few silt, trace gravel (SW) and 0 .. Sampler Type {ST) rn 2" OD Split Spoon Sampler (SPT) 0 No Recovery M-Moisture Logged by: SGS rn 3" OD Split Spoon Sampler (D & M) I] Ring Sample 'Q Water Level O Approved by: IQ] Grab Sample [ZI Shelby Tube Sample.!. Water Level at time of drilling (ATD) Associated Earth Sciences, Inc. Exoloration Loa ~ [TI ~ ~ [El Project Number I Exploration Number I Sheet .. KE070040A EB-6 2 of 3 -- Project Name Ney; Tran~i;lQctation Center Ground Surface Elevation (ft) Location Ri,nton WA Datum .111" Driller/Equipment Bortech Track Rig Date Start/Finish 212J/01 212J /OZ Hammer Weight/Drop 140# / 30" Hole Diameter (in) .AJnc,__.'.. C ~" 0 g 0 u-0 ;;; .!, ·-0 ;:::g " "' Blows/Foot " ~~ _, ., ~ a. ~[ ID-~ ~ f- C. s E s~ " 0 ~ " T ro C9" l a5 ~ " " 0 6 DESCRIPTION 0 10 20 30 40 occasional silt seams, weakly stratified. 0 ' Couple feet of heave/fell out. -45 2nd try failed again -no sample. Gravels and harder drilling reported by driller 45 to 49 feet. I S-9 Saturated, gray, silty SAND (SM), with gravel grading to gray, silty fine 0 ~,o -50 SAND, with tenses of peat and silt. 4 6 ~SJi.turated _g~ fine to medium SAND trace silt Giel__ Saturated, gray, SILT, with fine sand and lenses of peat and chunks of - wood (ML). -55 S-10 6 ... ,2 5 7 --------------------------------- S-11 Saturated, gray, fine to medium SAND {SP). trace silt. 0 .. , -60 Saturated, gray, SILT, with fine sand and peat stringers (ML). 0 3 S-12 lnterbedded, saturated, way, fine to medium SAND, with silt and stratified 7 A14 -65 sandy SILT, with very thin peat stringers (MUSM). 7 7 I Same as above. 0 -70 S-13 2 ... 2 S-14 Wet, gray, SILT, stratified, with fine laminae of peat, lenses of peat to 2 .. 8 -75 1-inch thick, and trace organics (ML) 6 12 S-1S Saturated, fine to medium SAND, with trace silt grading lo silty fine SAND 4 -I Sampler Type (ST) [I] 2" OD Split Spoon Sampler (SPT) D No Recovery M -Moislure Logged by: SGS [) 3" OD Split Spoon Sampler (D & M) [] Ring Sample 'CJ_ Water Level {) Approved by: IQ] Grab Sample IZJ Shelby Tube Sample.!. Water Level at time of drilling (ATD) Associated Eartl1 Sciences, Inc. Exoloration Loi:i ~ [1J ~ ~ m Project Number I Exploration Number I Sheet . . KE070040A EB-6 3 of 3 - Project Name New Ir;,nsQQrtation Center Ground Surface Elevation (ft) Location Rentoo WI:,, Datum ...!,I" Driller/Equipment Bortech Track Big Date StarUFin1sh 2121/0Z 212HOZ Hammer Weight/Drop 140# 130" Hole Diameter (in) 4 iocbes g cw 2 w u-0 >' ID -0 " !!' " .c-" =:g Blows/Foot " .c C. C.f _, w t-·-~ ~ 15. s E l'! " SE ~ • T ~ "U) $..Q .c 0 U) 0 ;: " DESCRIPTION 0 i5 10 20 30 40 (SP/SM) 7 12 S-16 Saturated, gray, silty fine to medium SAND, very weakly stratified, trace ' ... , -85 organics {SM). 14 21 -90 _ Wet._gray,_silty fine SAND weakly stratifi_ec:f~-- S-17 ·-------·------9 ... 8 15 Bottom of exploration boring at 90 5 feet 23 Ground water at 10 feet ~ 95 -100 -105 -110 I -115 I I Sampler Type (ST): [I] 2" OD Split Spoon Sampler (SPT) 0 No Recovery M -Moisture Logged by: SGS [I] 3" OD Split Spoon Sampler (D & M) I] Ring Sample 5J_ Water Level () Approved by: i;jJ Grab Sample lZI Shelby Tube Sample!. Water Level at time of drilling (ATD) Associated Earth Sciences, Inc. Date Sampled Project Project No. 2/22/2007 Renton Transfer Station KE070040A Tested By Location EB/EP Nol Depth MS Onsite Sample I.D. EB-3 25-200' EB-3 20' Wet Weight 902.2 1041.6 Dry Weight 822.4 903.7 Water Weight 79.8 137.9 Pan 512.8 510.9 Actual Dry Weight 309.6 392.8 Percent of Water Weight 25.8 35.1 After Wash Weight 639.1 710.5 Percent Passing #200 59.2 49.2 Sample I.D. EB-3 45' EB-3 25' Wet Weight 773.2 956.7 Dry Weight 734.3 781.1 Water Weight 38.9 175.6 Pan 518.4 410.4 Actual Dry Weight 215.8 370.8 Percent of Water Weight 18.0 47.4 After Wash Weight 707.6 521.2 Percent Passing #200 12.4 70.1 Sample I.D. EB-3 5-200' EB-3 10-200' Wet Weight 921.2 633.3 Dry Weight 830 3 61<1.0 Water Weight 90.9 19.3 Pan 392 9 3149 Actual Dry Weight 437.5 299.0 Percent of Water Weight 20.8 6.5 After Wash Weight 633.5 601.6 Percent Passing #200 45.0 4.1 Percent Passing #200 ASTM D 1140 Soil Description Various EB-3 35' EB-3 40' 668.1 531.1 592.3 488.4 75.8 42.7 297.2 312.1 295.1 176.3 25.7 24.2 532.2 451.7 20.4 20.8 EB-3 15-200' EB-3 30' 897.8 839.2 831.5 659.6 66.4 179.6 521 0 331.cl 310.5 327.7 21.4 54.8 816.9 389.6 4.7 82.4 ASSOC/A TED EARTH SCIENCES, INC. 911 5th Ave., Suite 100 Kirkland. WA 98033 425-827-7701 FAX 425-1:!27·5424 I EXPIRES 01/23/2008 ENGINEERING REPORT Technical Information RepMt Renton School District Transportation Center C060055-02 October 3, 2007 PREPARED FOR: Renton School District 1220 N 4th Street Renton, Washington 98055 PREPARED THROUGH: McGranahan Architects 2111 Pacific, Suite 100 Tacoma, Washington 98402 PREPARED BY: Coughlin Porter Lundeen 413 Pine Street, Suite 300 Seattle, Washington 98101 Phone: (206) 343-0460 Contact: Mr. Tim Brockway, P.E. TECHNICAL INFORMATION REPORT Renton School District Transportation Center Coughlin Porter Lundeen Project No. C060055-02 October 3, 2007 TABLE OF CONTENTS Page Section I. PROJECT OVERVIEW ...................................................................................................................................... 1 General Description ...................................................................................................................................................... 1 Existing Conditions ......................................................................................................................................................... 1 Proposed Conditions ...................................................................................................................................................... 2 II. CONDIDONS AND REQUIREMENTS SUMMARY ................................................................................... 2 King County Surface Water Management Design Manual Core Requirements: ................................................. 2 Special Requirements: .................................................................................................................................................... 3 Project Specific Requirements: ...................................................................................................................................... 3 III. OFF-SITE ANALYSIS ........................................................................................................................................ 4 Task 1 -Study Area Definition and Maps ................................................................................................................. 4 Task 2 -Resource Review . . .. .. . . .. . . . . .. . .. .. .. . .. . . .... ... ... . . . . . .. . .. . . . . . ... . . . . . . . . . . . . . . . . .................................................................... 4 Task 3 -Field Investigation ........................................................................................................................................... 4 Task 4 -Drainage System Description and Problem Screening..... . ................................................................... .4 Task 5 -Mitigation of Existing or Potential Problerns .............................................................................................. 5 IV. FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN ............................ 6 Part A-Existing Site Hydrology ............................................................................................................................... 6 Part B-Developed Site Hydrology.................................................... . .................................................................... 6 Part C -Performance Standards ......................................................... . .................................................................... 7 Part D -Flow Control System........................................................... . ................................................................... 7 Part E -Water Quality System ..................................................................................................................................... 7 Standard Requirements ................................................................................................................................................. 7 V. CONVEYANCE SYSTEM ANALYSIS AND DESIGN ................................................................................. 9 On-site Conveyance ....................................................................................................................................................... 9 VI. SPECIALREPORTSANDSTUDIES ................................................................................................................ 9 VII. OTHERPERMITS ................................................................................................................................................ 9 VIII. CSWPPP ANALYSIS AND DESIGN ............................................................................................................... 9 Part A -ESC Plan Analysis and Design.. ..................................................................................................................... 9 Part B -SWPPS Plan Design ....................................................................................................................................... 1 O IX. BOND QUANTIDES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT ...................... 11 X. OPERATIONS AND MAINENANCE MANUAL .................................................................................. 12 Standard Maintenance .............................................................................................................................................. 12 • COUGHLINPORTERLUNDEEN Renton School District Trarn;portation Center Renton, Washington FIGURE Figure 1 -TIR Worksheet Figure 2 -Site Location Figure 3a -Existing Drainage System Figure 3b -Proposed Drainage System Figure 4 -Soils Map Figure 5 -"Existing Conditions" Text Figure 6 -1979 Aerial Photo of Site LIST OF FIGURES Figure 7 -Definition of "Impervious" from Renton Municipal Code Figure 8 -1990 KC Manual Conditions of Exemption from Detention UST OF TABLES Table 1 -Existing Site Conditions Area Breakdown ................................................................................................... 6 Table 2 -Developed Site Conditions Area Breakdown........................... ........................................................ . ... 6 Table 3 -Summary of EcoStorm Plus System for Bus Parking...................................................................... . ....... 8 Table 4 -Summary of EcoStorm Plus System for Employee Parking........................................................ . ........... 8 Table 5 -Summary of Oil/Water Separator for "High-Use" Area ........................................................................... 8 APPENDICES Appendix A Appendix B AppendixC Appendix D Appendix E Figures Supporting calculations • Water Quality • Conveyance • Backwater (not provided at this time) • T.E.S.C. (not provided at this time) Geotechnical Reper! Bond Quantities, Facility Summaries, and Declaration of Covenant (not provided at this time) Operations and Mainte,;,ance Manual (not provided at this time) COUGHLINPORTERLUNDEEN Renton School District Transportation Center Renton, Washington ii I. PROJECT OVERVIEW General Description The following Technical Information Report (TIR) provides the technical information and design analysis required for developing the Drainage Plan for the Renton School District Transportation Center. The Renton School District Transportation Center is located at 1220 North 4u, Street in Renton, Washington (see Figure 2- Site Location) in King County and is located within the Lower Cedar River drainage basin. The existing site consists of four buildings, surrounded by gravel and asphalt bus parking; there is also an existing on-site fuel station. The terrain is fairly flat, falling generally north and west from U1e southeast corner. The Renton School District is proposing the removal of the existing on-site buildings and related utilities along with the removal of the existing fuel station. The existing m1derground fuel tanks are being analyzed to confirm their compliance with current code. They are expected to remain and be re-used for the proposed fuel station. The District is proposing to construct a new maintenance building along with associated parking lots for buses and employees, a new fuel station, and bus wash. The existing maintenance building will remain operational during the first phase of construction of the new project, and once the new building is operational the existing building will be demolished and replaced with parking area. The existing site consists of 81,941 SF of gravel paving, 104,582 SF of asphalt and concrete paving, and 23,204 SF of building area. The total site area for the project is approximately 4.8 acres. The proposed site will consist of 162,200 SF of asphalt and concrete paving, and a building footprint of approximately 17,000 square feet; resulting in approximately 179,200 SF of proposed impervious area, for a total reduction of 30,500 square feet of impervious area on the site. Stormwater runoff from this site will sheet flow to a closed pipe system. The section of the parking used for the school buses is classified as "high use" and will be routed through an oil/ water separator due to Special Requirement #5 of the KCSWDM. This runoff will also be routed through an EcoStorm Plus water filtration system. The employee parking area will be routed through a separate EcoStorm Plus water filtration system before combining with the bus parking flows. Once these two flows have been combined, they will discharge to an existing catch basin in the City storm system in North 5th Street. Existing Conditions The existing Renton School District Transportation Center occupies approximately 4.8 acres and consists of the main transportation maintenance building, the facilities building, and two associated storage buildings. Around these buildings are a fueling station and a patchwork of impervious gravel and asphalt parking for the buses and employee vehicles. There are presently no storm water detention or water quality facilities on the site. The project is located within the Lowet Cedar River Drainage Basin which ultimately drains to Lake Washington. Currently most of the site drains to the north through the site to the City storm system in North 5th Street. A small portion of the southeast corner drains south the City storm system in North 4th Street. Once in the city storm system the flows drain into the Cedar River which then discharges into Lake Washington. (See Figure 3a -Existing Drainage System). The on-site soils consist mainly of Quaternary alluvium and fill material. The upper three feet is the fill material, which is a silty sand with gravel in a loose to medium dense condition. Below this three feet of fill is the alluvium which is interbedded clean sand, silty sand, clayey and lean silt with occasional lenses of gravel, peat, and other organics. The alluvium was deposited by the former channels of the Cedar River. (See Figure 4 for the USGSsoils map). COUGHLINPORTERLUNDEEN 1 Renton School Disrrict Transportation Center Renton, Washington Proposed Conditions The proposed Renton School District Transportation Center will consist of a new two story building, parking lots for the school buses and employees, a fuel station, and a bus wash. Drainage improvements will include curbs and a combination of trench drains and catch basins on-site to direct flows to the existing outlet in Nortl1 5,h Street. (See Figure 3b -Proposed Drainage System). As previously stated, storm water quality treatment will be provided on-site. For the bus parking area, an oil/water separator along with an EcoStorm Plus stormwater filter will be provided since it is classified as a high use system. The employee parking will utilize a separate EcoStorm Plus stormwater filter system. Both of these water quality treatment systems will have high flow bypasses due to the volume of runoff from the site. The determination for the Renton School District Transportation Center's need to provide detention was based on the requirements set forth in the 1990 King County Surface Water Design Manual (KCSWDM) while the design for the site stormwater system was based on the requirements set forth in the 2005 King County Surface Water Design Manual. This site does not require detention since it is being reviewed under the requirements set forth in the 1990 KCSWDM and as required by City cod. See Section IV of this report for further discussion. II. CONDITIONS AND REQUIREMENTS SUMMARY This section will address the requirements set forth by the Core and Special Requirements listed in Chapter 1 of the KCSWDM. King County Surface Water Management Design Manual Core Requirements: J. Discharge at a natural location (1.2.1): The existing and proposed discharge points are concurrent. While we are no longer discharging any stormwater to the southwest corner of the site, all site runoff will be discharging at the existing discharge point in North 5th Street. 2. Off-site Analysis (1.22): This subject is covered in Sections III and IV. Please refer to the Level 1 downstream analysis in those sections. 3. Flow Control (1.2.3): This project does not require flow control due to the requirements set forth in the 1990 KCSWDM and City code. Please refer to Section N of this report for the discussion of this requirement. 4. Conveyance System (1.2.4): This information and calculations are presented in Section V. A closed pipe systems has been provided for on-site storm water conveyance. 5. Erosion and Sediment Control (1.2.5): The project will construct a series of sediment controls to address the specific conditions at the site. Further detail will be presented in Section IX at the time of the permit submittal. 6. Maintenance and Operation (1.2.6): The proposed storm drainage system will be owned, operated and maintained by the owner. A maintenance and operation manual will be included in Section XI of this report at the time of permit submittal. COUGHLINPORTERLUNDEEN 2 Renton School Dishict Transportation Center Renton, Washington 7. Financial Guarantees and Liability (1.2. 7): The owner and contractor will obtain all necessary permits prior to the beginning of construction. The owner will be responsible for required bonds. 8. Water Quality (1.2.8): This project will provide one water quality oil/ water separator, and hvo water quality filter systems, designed in accordance with the KCSWDM and the Department of Ecology. Special Requirements: Special Requirement #1. Other Adopted Area-Specific Requirements Section 1.3.1 • Critical Drainage Areas (CDAs): Not Applicable • Master Drainage Plans (MDPs): There are no known master drainage plans covering this project site. • Basin Plans (BPs): The project is located within the Lower Cedar River Basin Plan. There are no area specific drainage review thresholds for this area. • Salmon Conservation Plans: Not Applicable • Stormwater Compliance Plans: Not Applicable • Lake Management Plans(LMPs): Not Applicable • Flood Hazard Reduction Plan Updates: Not Applicable • Shared Facility Drainage Plans(SFDPs): Not Applicable Special Requirement #2. Floodplain/Flood way Delineation, Section 1.3.2: This project is not within a designated flood plain. Special Requirement #3. Flood Protection Facilities, Section 1.3.3: Not Applicable Special Requirement #4. Source Control, Section 1.34: The site will contain a covered bus wash which will be equipped with its own oil filtration system and will drain to the site sewer system. Special Requirement #5. Oil Control: The portion of this site used for bus storage and maintenance is considered "high-use". An oil/water separator along with the standard water quality level filtration system will be installed to treat the stormwater runoff prior to discharge into the City storm system. Project Specific Requirements: There are no project specific requirements. COUGHLINPORTERLUNDEEN 3 Renton School District Transportation Center Renton, Washington III. OFF-SITE AN AL YSIS Task I -Study Area Definition and Maps See Figure 3a for drainage sub-basins, discharge points from the site and other related information. Task 2 -Resource Review a) Adopted Basin Plans: b) Finalized Drainage Studies: c) Basin Reconnaissance Surrunary Reports: d) Critical Drainage Area Maps: e) Floodplain/ floodway (FEMA) Maps: f) Other Offsite Analysis Reports: g) Sensitive Areas Folio: h) Drainage Complaints and Studies: i) Road Drainage Problems: j) King County Soils Survey: k) Wetland Inventory Maps: 1) Mitigating River Studies: Task 3 -Field Investigation Lower Cedar River Basin -does not effect project site. No information provided effects site work. No information found for the Cedar River. Not in critical Drainage areas. Site not in 100-yr Floodplain No other reports available. Site is not part of a sensitive area. No record of drainage complaints No record of road drainage problems Soils information has been included, See Figure 4. Site is not within a wetland River mitigation does not effect site work. A site visit has been made to the project site to gather information including a Level 1 Downstream Analysis. Please refer to the discussion below. Task 4 -Drainage System Description and Problem Screening Upstream Drainage Review The Renton School District Transportation Center site is located on a slight slope that runs down to the northwest corner of the site. The grades in the surrounding streets are in most cases lower than the site grading. The exception is at the comer of North 4u, Street and NE Garden St. The drainage from this area and other surrounding streets is picked up in the existing city storm system. No flows therefore enter the school property from upstream. Level 1 Downstream Drainage Review On August 13th, 2007 the following observations were made while researching the downstream drainage of the Renton School District Transportation Center. The weather was good and the temperature was approximately 76 F. The exploration started at about 9:00 and ended around 10:30. The majority of the site drains through the on-site storm system and out into North 5th Street. There is a small section of the site, approximately 0.4 acres, in the southwest corner that drains into North 4th Street. The runoff entering the city storm system in North 5th Street flows approximately 1000 feet west to Burnett Ave N where is turns North and flows roughly 500 feet to North 6th Street. At North 6th Street the city COUGHLINPORTERLUNDEEN 4 Renton School District Transportation Center Renton, Washington system turns and heads west again about 1,300 feet to a discharge point into the Cedar River. The Cedar River flows approximately 3,500 feet before depositing into Lake Washington. The smaller section of the site that enters the city system in North 4u, Street, flows west through the city system down North 4th Street approximately 1,000 feet until it turns south down Burnett Ave N. It then flows south down Burnett Ave N about 1,000 feel before turning southwest and running roughly 250 feet before discharging into the Cedar River. This discharge point into the Cedar River is approximately 3,000 feet upstream of the North 5th Street storm system discharge location. Task 5 -Mitigation of Existing or Potential Problems There are no existing or foreseen potential problems that require ntitigation . • COUGHLINPORTERLUNDEEN 5 Renton School Dishict Transportation Center Renton, Washington IV. FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN This section describes fue conditions that contribute to fue storm water runoff values and mitigation efforts proposed for the site. Part A -Existing Site Hydrology The existing site hydrology consists of four existing buildings and associated improvements. There are existing established storm water runoff conveyance lines, however, there are no flow control or water quality treatment facilities on the site. The total site area is 4.8 acres. The existing site conditions are shown in Figure 3a, from a documented field survey. The site is generally flat with a soft slope to fue northwest corner. The majority of the site drains out to the existing City storm out in North 5"' Street while a small section of the southwest corner drains out to the existing City system in North 4u, Street. The existing site conditions are summarized in Table 1 below. Drainage Basin Lower Cedar Creek Table 1 -Existing Site Conditions Area Breakdown Land Cover Area (acres) Impervious Area 4.8 Pervious Area 0.0 Total 4.8 Total Site 4.8 Description Buildings, Gravel and Asphalt Parking lots Landscaping Existing Transportation Center Site Part B -Developed Site Hydrology The proposed drainage of the site will generally be similar to the existing system. The entire site will now flow to the northwest corner where it will discharge in the existing location to North 5u, Street. Please refer to Figure 3b for proposed drainage information. The developed site conditions are summarized in Table 2 below. Drainage Basin Lake Washington Table 2 -Developed Site Conditions Area Breakdown Land Cover Area (acres) Description C Impervious Area Pervious Area Total Total Site 4.1 Building, asphalt parking, concrete walks 0.7 Landscaping ------4.8 4.8 Proposed Transportation Center Site COUGHLINPORTERLUNDEEN Renton School District Tran.'iportation Center Renton, Washington 6 Part C -Performance Standards • Area-Specific Flow Control Facility Standard -Site is part of an incorporated area. Flow control will not be provided for this site. See discussion in Part D of this section. • Conveyance System Capacity Standards -Conveyance calculations are included for the on-site system in the appendix. • Area-Specific Water Quality Treatment-Basic Water Quality will be provided for this site with the use of Ecology approved EcoStorm Plus water filtration systems. An oil/water separator will also be provided for the portion of this site that is classified as "high-use". Part D -Flow Control System Per the site pre-application meeting with the City of Renton, the 1990 King County Storm Water Drainage Manual is to be used as the basis for threshold determination of whether flow control is required for this site. In the 1990 KCSWDM, the existing site conditions can be modeled after the conditions that existed prior to May of 1979 as long as they are documented with an aerial photograph (See Figure 5). An aerial photo from 1977 (see Figure 6) has been provided to show the site "existing conditions" are the same as the current site. As can be seen in the photo, the site consisted of four buildings and a combination of asphalt and gravel parkmg lots. Per the Renton Municipal Code gravel parkmg is considered in1pervious (see Figure 7). Therefore the entire site existing condition is modeled as impervious area. The proposed site consists of 0.7 acres of pervious surfacing; therefore, we are reducing the total site impervious area. In reducing the site impervious coverage, we are reducing the post-developed peak flow. This means, according to the 1990 KCSWDM, that this site is exempt from runoff control (see Figure 8). For this reason no flow control is provided for the proposed site plan. Part E -Water Quality System Standard Requirements There are three levels of water quality facilities defined in the 2005 Surface Water Design Manual in the Water Quality Applications Map. These levels are as follows: 1. Basic Water Quality Treatment Areas 2. Enhanced Basic Water Quality Areas 3. Sensitive Lake Treatment Areas 4. Sphagnum Bog Protection Areas 5. High-Use Areas This project will provide water quality in accordance with basic water quality requirements of the KCSWDM (section 6.1.1) by installing EcoStorm Plus water filtration systems. The site is divided by curbing and grading to create two "basins". The first "basin" is for the bus parkmg; this area is considered "high-use" per the KCSWDM and requires additional treatinent. A coalescing plate oil/water separator will be installed prior to the EcoStorm Plus to meet the additional treatinent requirements. The second "basin" is for the employee parking. Which has been separated from the bus parking because it does not require the extra treatment; an EcoStorm Plus filtration system will be used in this "basin" as well for the basic water quality treatinent. In order to provide water quality treatinent on the heavily paved site without backing up COUGHLINPORTERLUNOEEN 7 Renton School District Transportation Center Renton, Washington the storm system, it was necessary to provide high-flow bypasses for both basins. See Tables 3 and 4 below for a summary of the water quality structures and Appendix B for water quality calculations. Table 3 -Summary ofEcoStorm Plus System for Bus Parking Water Quality System EcoStorm Plus Pervious Area 2.85 acres Impervious Area 0.06 acres Total Area 2.91 acres Water Quality Flow 0.83 cfs (See Calculations in Appendix B) Table 4 -Summary of EcoStorm Plus Svstem for Employee Parking Water Quality System EcoStorm Plus Pervious Area 1.19 acres Impervious Area 0.10 acres Total Area 1.29 acres Water Quality Flow 0.35 cfs (See Calculations in Appendix B) Due to the site having bus storage, it is classified as "high-use". This "high-use" classification triggers the special requirement #5: oil control. Oil control will be provided for the portion of the site that is considered "high-use" by an oil/water separator. The oil/water separator will be designed using the 2005 KCSWDM. The oil/water separator must be designed for the water quality flow only, so a high flow bypass will be designed to route additional flow around the vault. The separator will be placed prior to the EcoStorm Plus system to provide the necessary treatment train for the bus parking area. See Table 5 below, for a summary of the oil/ water separator. Table 5 -Summary of OiVWater Separator for "High-Use" Area Water Quality System Oil/Water Separator Petvious Area 2.85 acres Impervious Area Total Area Water Quality Flow Vault Size (based on Flow) (See Calculations in Appendix B) COUGHLINPORTERLUNDEEN 0.06 acres 2.91 acres 0.83 cfs 7 feet x 5 feet 8 Renton School Di,;trict Transportation Center Renton, Washington V. CONVEYANCE SYSTEM ANALYSIS AND DESIGN -------------------------~ On-site Conveyance l11e on-site conveyance system will consist of Type 1 and Type 2 catch basins, eight, 12, and IS-inch conveyance lines, two EcoStorm Plus filtration systems and an oil/water separator. The capacity of the on- site lines was evaluated using the Rational Method and a Manning's-based conveyance spreadsheet. If pipe capacity is questionable, energy grade elevation will be evaluated using the Direct Step Backwater Method at the time of permit submittal. The conveyance system has been designed to provide adequate slopes and sizes. Refer to Appendix B for conveyance calculations and sub-basin maps and areas. VI. SPECIAL REPORTS AND STUDIES See appendix C for geotechnical report. VII. OTHER PERMITS An NPDES permit will be required for this project. VIII. CSWPPP ANALYSIS AND DESIGN Part A -ESC Plan Analysis and Design Erosion/Sedimentation Plan shall include the following: 1. Facilities required include: stabilized construction entrance, sedimentation pand, interceptor swales, filter fabric fencing. (1.25-1). The project will provide two construction entrance/ exits, truck wheel washes, filter fabric fencing, a sediment tank, slope stabilization, catch basin protection and interceptor swales. 2. Timing -For the period between November 1 through March 1 disturbed areas greater than 5,000 square feet left undisturbed for more than 12 hours must be covered with mulch, sodding, or plastic covering. A construction phasing plan shall be provided to ensure that erosion control measures are installed prior to clearing and grading. (1.2.5-1). Notes adi'lressing each of these items will be placed on the civil engineering plans. 3. Planning -Plan shall limit tributary drainage to an area to be cleared and graded. Delineate dimension, stake and flag clearing limits (1.2.5-1). The clearing limits will be indicated on the TESC plan. Notes addressing this item will be placed on the civil engineering plans. 4. Re-vegetation -Re-vegetate areas to be cleared as soon as practicable after grading. (1.2.5-1). Notes addressing this item will be placed on the civil engineering plans. COUGHLINPORTERLUNDEEN 9 Renton School District Transportation Center Renton, Washington The TESC plan for this project will be designed to protect off-site properties as well as to minimize the quantity of sediment-laden water that enters the public storm system. The following BMP's will be included on the TESC p Ian for this project. • Clearly delineated clearing limits staked prior to any construction activity. • Stabilized construction entrances with a wheel washing station for trucks exiting the site. All material that is tracked off the site will be cleaned by sweeping. • Catch basin protection will be used on all existing and future catch basins as they are installed, to reduce the amount of sediment that can enter the storm system. • Cover measures will be implemented for disturbed areas greater than 5,000 square feet in accordance with the King County standards. • Temporary sediment tanks will be included, if necessary, to allow the opportunity for sediment to settle out of on-site runoff prior to discharging from the site. All construction debris will be promptly removed from the site to minimize demolition and construction impacts to the site. The contractor will implement additional BMP's as required or recommended by the City of Renton inspectors or other agencies as required. This will help prevent demolition and construction debris, waste material, fuel, oil, lubricants and other fluids from entering tl1e public storm system. These measures will be shown on the TESC plan sheets included in the construction permit set. Part B -SWPPS Plan Design The site SWPPP will be completed by the project contractor and based on the civil TESC plan. COUGHLINPORTERLUNDEEN 10 Renton School District Transportation Center Renton, Washington IX. BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT Bond Quantity Worksheets Bond quantity worksheets will be included in Appendix E for the permit submittal. Flow Control and Water Quality Facility Summary Sheet and Sketch Water quality summary and sketch will be included in Appendix E for the permit submittal. Declaration of Covenant for Privately Maintained Flow Control and WQ Facilities Declaration of Covenant will be included in Appendix E for the permit submittal. Declaration of Covenant for Privately Maintained Flow Control BMPs Declaration of Covenant will be included in Appendix E for the permit submittal. COUGHLINPORTERLUNDEEN 11 Renton School District Transportation Center Renton, Washington X. OPERATIONS AND MAINENANCE MANUAL Standard Maintenance Per standards set forth in the King County Surface Water Design Manual, the mvner will maintain facilities. Sections of the King County Storm Water Management Design Manual outlining the Operations and Maintenance of these facilities will be included in Appendix F. (not included in this report) COUGHLINPORTERLUNDEEN 12 Renton School Dishict Transportation Center Renton, Washington ' I ., . . . . . . . ' . I " • .. • _: ! . -. . . . . • ;I ~ • ,' • • ' . • • .. • • • ' • ' APPENDIX A Figure 1 -TIR Worksheet Figure 2 -Site Location Figure 3a -Existing Drainage System Figure 3b -Proposed Drainage System Figure 4 -Soils Map Figure 5 -"Existing Conditions" Text Figure 6 -1979 Aerial Photo of Site Figure 7 -Definition of "Impervious" from Renton Municipal Code Figure 8 -1990 KC Manual Conditions of Exemption from Detention COUGHLIN PORTER LUNDEEN Renton School District Transportation Center KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND PROJECT ENGINEER Project Owner Rem.on School District #403 Phone 42s-204-4429 Address 1220 N 4th street Renton WA 98055 Project Engineer Tim Brockway Company Coughlin Porter Lundeen Phone 2G0-343-046o Part 3 TYPE OF PERMIT APPLICATION D Landuse Services Subdivison / Short Subd, / UPD ~ Buildinn Services M/F /,~~/ SFR D Clearing and Grading D Right-of-Way Use ~ Other Site Plan Review Part 5 PLAN AND REPORT INFORMATION Technical Information Report Type of Drainage Review @!I) I Targeted (circle): Large Site Date (include revision 10/3/07 dates): Date of Final: Part 6 ADJUSTMENT APPROVALS I Part 2 PROJECT LOCATION AND DESCRIPTION Project Name -Renton School District Transit Center ODES Permit# __________ _ Location Township ~2~3~N ___ _ Range ---=-s~E=---------- Section _, ______ _ Site Address 1220 N 4th Street Renton , WA 98055 Part 4 OTHER REVIEWS AND PERMITS D DFW HPA 0 COE404 0 DOE Dam Safety D FEMA Floodplain D COE Wetlands D Other __ _ D Shoreline Management D Structural RockeryNault/ __ D ESA Section 7 Site Improvement Plan {Engr. Plans) Type (circle one): ®[Ci/ Modified I Small Site Date (include revision 10/3/07 dates): Date of Final: Type (circle one): Standard / Complex I Preapplication / Experimental I Blanket Description: {include conditions in TIR SeG)ion 2) Date of Annroval: 2005 Surface Water Design Manual 1/1105 1 ' KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 7 MONITORING REQUIREMENTS Monitoring Required: Yes /!No', Describe: "-'--~,, Start Date: Completion Date: Part 8 SITE COMMUNITY AND DRAINAGE BASIN Community Plan : -------------- Special District Overlays:------------------------ Drainage Basin: Lower Cedar River Stormwater Requirements: _B=a=s=i~c~W~a=te=r~Q~u=a=l=i=ty~-------------- Part 9 ONSITE AND ADJACENT SENSITIVE AREAS D River/Stream _________ _ D Steep Slope _________ _ D lake D Erosion Hazard _______ _ D Wetlands __________ _ D landslide Hazard _______ _ D Closed Depression _______ _ D Coal Mine Hazard _______ _ D Floodplain __________ _ D Seismic Hazard _______ _ D Other ___________ _ D Habitat Protection -------- D ----------- Part10 SOILS Soil Type Slopes Erosion Potential Alluvium 0-2% D High Groundwater Table (within 5 feet) D Sole Source Aquifer D Other ~ D Seeps/Springs D Additional Sheets Attached 2005 Surface Water Design Manual 2 1/1/05 KING COUNTY, WASHINGTON, SURFACE WATER DESIG:sl MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 11 DRAINAGE DESIGN LIMITATIONS REFERENCE LIMITATION/ SITE CONSTRAINT 0 Core 2 -Offsite Anal~sis D Sensitive/Critical Areas D SEPA D Other D 0 Additional Sheets Attached Part 12 TIR SUMMARY SHEET lnrovide one TIR Summarv Sheet oer Threshold Discharae Areal Threshold Discharge Area: (name or description\ Develoned Stie Core Requirements (all 8 apply) Discharae at Natural Location Number of Natural Discharae Locations: 2 Off site Analysis Level'. (Di 2 / 3 dated: August 13th, 2007 . Flow Control Level: 1 / 2 / 3 or (J;}emptiq/i' Number /incl. facilitv summary sheet) Small Site BMPs Conveyance System Spill containment located at: EcoStorm Filters Erosion and Sediment Control ESC Site Supervisor: Contact Phone: TBD After Hours Phone: Maintenance and Operation Responsibility: C Privat~ / Public If Private, Maintenance Lon Renuired: (yes)/ No Financial Guarantees and Provided: Yes / No TBD Liabilitv Water Quality Type: <tiasic_i/ Sens. Lake / Enhanced Basicm / Bog (include facility summary sheet) or Exemption No. Landscaoe Management Plan: Yes / (Igo) Soecial Requirements (as annlicable) Area Specific Drainage Type: CDA / SDO /MOP/ BP/ LMP / Shared Fae. /~ Reauirements Name: Floodplain/Floodway Delineation ~ Type: Major / Minor / Exemption / (flan~ 100-year Base Flood Elevation (or range): Datum: Flood Protection Facilities Describe: None Source Control Describe landuse: Commercial (comm./industrial landuse) Describe any structural controls: None 2005 Surface Water Design Manual 3 1/1/05 KING COUNTY, WASIIINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Oil Control High-use Site: c::@§) I No Treatment BMP: Oil[water se12arator and EcoStorm Maintenance Agreement: Yes / ()\J_q) with whom? Other Drainaae Structures Describe: Part 13 EROSION AND SEDIMENT CONTROL REQUIREMENTS MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION AFTER CONSTRUCTION D Clearing Limits l2iJ Stabilize Exposed Surfaces fEI Cover Measures l2iJ Remove and Restore Temporary ESC Facilities !ill Perimeter Protection l2iJ Clean and Remove All Silt and Debris Ensure l2iJ Traffic Area Stabilization Operation of Permanent Facilities !El Sediment Retention D Flag limits of SAO and open space D Surface Water Control preservation areas D Other l2iJ Dust Control !ill Construction Seauence Part 14 STORMWATER FACILITY DESCRIPTIONS (Note: Include Facility Summary and Sketch) Flow Control Tvoe/Description Water Quality Type/Description D Detention D Biofiltration D Infiltration D Wetpool D Regional Facility !ill Media Filtration D Shared Facility !El Oil Control D Small Site BMPs D Spill Control D Other D Small Site BMPs ~ D Other 2005 Surface Water Design Manual 4 1/1/05 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 15 EASEMENTS/TRACTS Part 16 STRUCTURAL ANALYSIS D Drainage Easement D Cast in Place Vault D Access Easement D Retaining Wall D Native Growth Protection Covenant D Rockery > 4' High (J Tract D Structural on Steep Slope D Other D Other Part 17 SIGNATURE OF PROFESSIONAL ENGINEER I, or a civil engineer under my supervision, have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attached Technical Information Report. To the best of my knowledge the information proviS!ec! her~ accurate. /FLC_ / L... _______________ 1J1~~.,,"''ifl~Da-,te---------------- l' 2005 Surface Water Design Manual 5 1/1/05 NISlhSl NSl!'IS! • r ' ' 2 . , COUGHLINPORTERLUNDEEN A CONSULTING STRUCTURAL AND CML ENGINEERING CORPORATION i: ,, • 2 N3mS1, 1220 North 4'" Street Renton, WA ; 2 ®fl ;. / ; Figure 2 -Vicinity Map Project: Renton School District Transportation Center Designed By: CMP Date: 10/3/07 Project No. C060055-02 Client: McGranahan Checked By: TBB Sheet 1 of 1 413 Pine Street• Suite 300 • Seattle, WA • Phone (206) 343-0460 • Fax (206) 343-5691 - COUGHLIN PORTERLUNDEEN A CONSULTING STRUCTURAL AND CIVIL ENGINEERING CORPORATION ----_ -__ ! PROJE.~CT~: -~R~EN~TO~N-~SC~HO~O~L~ DIS~TR~IC~T~TR~AN~Sl~T~CE~NT_=ER~--DESIGNED BY: CMP DATE: 10.03.07 PROJECT NO. C06-0055-02 CHECKED BY: TB_B --~FIG~UR~E 3A · EXISTING CONDITIONS 413 PINE STREET. SUITE 300 SEATTLE, WA 9810 I P: 206/343-0460 F: 206/343-569 I .S :c Q 0 0 0 I ;-~i -ru: \ 'CL.( I \ " I ii COUGHLIN PORTERLUNDEEN A CONSUL TING STRUCTURAL AND CIVIL ENGINEERING CORPORATION " I. I ·.1[ ,n I I c', I I 111 ,;, f.c-C---ti"'6r--'-c£--'='.._--....-...--!;,sl---'--t-'-'=-5'3=~------"'-&cr------1...-~ !ls;;;i;;;~d!JJ1/lc:3I;p~ 0 !~~···:::'1:::'~··~·-·-~-~··~···~·-···~·-···§:':···=····=··~·=···13~~==-~··§··~~··~=-IN::· ~~~4;~.·gs~tr·~ee~t~~I~~,J,~~fi.~~~~~~-_J ~PR=OJ=ECc..cT:0 __ =RE=NT~ON,__,SCHOOL DISTRICT TRANSIT C=EN=TE=R __ _ _DES_IG_NED~BY:'----_C=M~P --~DA=T=E:~1=0.0=3.07'------ CHECKED BY_: __ TB_B __ JIGURE 38 -PROPOSED CONDITIONS PROJECT NO. COS-0055-02 413 PINE STREET-SUITE 300 SEA TILE, WA 98 IO I P: 206/343-0460 F: 206/343-5691 COUGHLINPORTERLUNDEEN A CONSULTING STRUCTURAL AND CIVIL ENGINEERING CORPORATION Figure 4 -Soils Map Project: Renton School District Transportation Center Designed By: CMP Date: 10/3/07 Project No. C060055-02 Client: McGranahan Checked By: TBB Sheet 1 of 1 413 Pine Street • Suite 300 • Seattle, WA • Phone (206) 343-0460 • Fax (206) 343-5691 ' . KING COUNTY, WASHINGTON, SURFACE WATER DES I G N MANUAL Sites with Existing Approved Drainage Systems: The proposed project site "existing site conditions" are defined as those that occur with the existing drainage facilities constructed per approved permits and engineering plans when required. The current performance of existing drainage and detention facilities shall be determined by using the analysis methods described in Section 3.5. · Sites with No Existing Approved Drainage Systems: The "existing site conditions" are defined as those that existed prior to May 1979. This is the date of publication of "Requirements and Guidelines for Storm Drainage Control in King County" by the King County Public Works Department's Hydraulics Division, the document which defined the on-site detention design criteria for implementing King County Ordinance 2281. If in question, .the "existing site conditions" must be documented by the best available aerial photographs. If aerial photographs are not available, knowledge of the site by individuals familiar with the area will be admissible. Peak Rate Runoff Control Performance Curve A "peak rate runoff control performance curve" plots the allowable peak runoff rates for a range of design storm frequencies, as illustrated in Figure 1 .2.3A the "Standard Peak Rate Runoff Control Performance Curve". In the absence of other Special Requirements which dictate a more thorough analysis, the BALD Division evaluates peak rate runoff control only for the 2-, 10-, and 1.QQ:year frequency storm events represented on this curve. Peak rate runoff control facilities must be designed to produce post-development peak runoff rates at or below this curve for the 2-and 10- year, 24-hour duration design storm events. More restrictive runoff control performance curves may be required under conditions specified in the "Special Requirements" section of this chapter. FIGURE 1.2.3A STANDARD PEAK RATE RUNOFF CONTROL PERFORMANCE CURVE [B ~00 I- <i:: a: LL LL 0 z 010 ::, -a: en ~ ....: <i:: ~ w 0.. O:z For 1he.100-year, 24-hour design storm event, 1he peak rate runoff control facility release rate depends on the significance of downstream impacts. • ••• . .. .. ,.i·" ,.,. .......... .... ,. .. .... .. .. \...... .. ...... Pre-development peak rates (allowable release rates)· ...... .. ...... .......... ............ ,.,. .................. : .... ,.. ........ ,.............. : .... "'.. ................... ' .. , ............ ,: ~,. .............. .. . ........ : Post-development peak rate runoff ~---...-control facility release rates. ' ' ' ' ' ' ' ' ' ' : : I ' 2 10 100 24 HOUR DESIGN STORM FREQUENCY (YEARS) 1.2.3-2 Figure 5 11/92 I I I I I I I I I I I . I I I I I I I I I I © 41:itO-Ml'f:'tC "'tiS l"'MOTO Ci•f ;:,,, ". · ,. ,, ~· •··, .. ; ~f\i-l(/ .. ~JJ.. V-if:'i .:::.:,~ .,,,> ··,r,;,i ~!:RM':v: ; •. /.,'.,-, j;"-;; ;..,;,. 3 -~· ·-; d !:-~.\li1.E1 WA 9~;~J • {.,::>.:,) :u;..-;.-:t:J~J www.~1 o;~:.:ric.corn .\llt0,Ml1lti( MO'tcl fl!I .1 MltlffllC Ne fttOtOOWHI IM t :• l'NU NlllUIIAH AVNll l6UfM 11,t.ffl.l WA MIU •-P.•*""'=_j;{I-)'? ?;'S'· a: ·-~ '.1.-,..~-"'-i~g ... }f-/ 2.. -? ? . I ,1-= /1"'1~.) / \.. ".g~ MM It Mf4; s , ...,,,, , ; ~-(/I-(/ ff ]7<((( 7 Figure 6 Page 2 of 2 IMPERVIOUS SURFACE: Any material that sub- stantially reduces or prevents the infiltration of stormwater into the surface of the ground, includ- ing graveled driveways and parking areas. INCOMBUSTIBLE AND NONCOMBUSTIBLE MATERIAL: Incombustible and noncombustible as applied to building construction material means a material which, in the form in which it is used, is either one of the following: A. Material of which no part will ignite and bum when subjected to fire. Any material conforming to U.B.C. Standard No. 4-1 shall be considered noncombustible within the meaning of this Sec- tion. B. Material having a structural base of noncom- bustible material as defined in subsection A above, with a surfacing material not over one- eighth inch (1/8") thick which has flame-spread rating of 50 or less. 'Noncombustible" does not apply to surface finish materials. Materials required to be noncombusti- ble for reduced clearances to flues, heating appli- ances, or other sources of high temperature shall refer to material conforming to subsection A above. No material shall be classed as noncom- bustible which is subject to increase in cor)lbusti- bility of flame-spread rating beyond the limits herein established, through the effects of age, moisture or other atmospheric condition. "Flame-spread rating" as used herein refers to rating obtained according to tests conducted as specific in U.B.C. Standard No. 42-1. (Ord. 3719, 4-11-1983, Amd. Ord. 4577, 1-22-1996) 11 -23 4-11-100 INCORPORATION BY REFERENCE: The inclu- sion of all of part of any existing document in an agency's environmental documentation by refer- ence (WAC 197-11-600 and 197-11-635). (Ord. 3891, 2-25-1985) INDUSTRIAL USE: A type of land use character- ized by production, manufacturing, distribution or fabrication activities. INDUSTRIAL USE, HEAVY: A type of land use including manufacturing processes using raw ma- terials, extractive land uses or any industrial uses which typically are incompatible with other uses due to noise, odor, toxic chemicals, or other activ- ities posing a hazard to public health and safety. INDUSTRIAL USE, LIGHT: A type of land use in- cluding small scale or less intensive production manufacturing, distribution or fabricating activi- ties. May also include office and supporting con- venience retail activities. INDUSTRIAL WASTES: See RMC 4-6-100. INFILL: Development that occurs on vacant land within urbanized areas. INFILTRATION: See RMC 4-6-100. INSTITUTION, EDUCATIONAL: A group of structures or facilities owned or associated with a public or private college or university, vocational or technical school. INSTITUTION, MEDICAL: A group of structures or facilities owned by or associated with a public or private hospital licensed by State law. A com- plex of functionally interrelated buildings housing medical services and/or medical research organi- zations or foundations, and typically including uses, such as, but not limited to: hospitals, diag- nostic centers, offices for physicians, support staff, and administrators; laboratories; clinics; hospices; congregate care facilities; convales- cent centers, retirement residences; and their ac- cessory uses including medical support facilities and services. (Ord. 4649, 1-6-1997) 4-11-100 DEFINITIONS J: (Reserved) Figure 7 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL Infiltration facilities must be designed based on infiltration testing and a soils report prepared by _:;y professional civil engineer with expertise in soil engineering. To maintain outflow rates of the infiltration tanks and ponds, all inflow must be pretreated for sediment removal (see Section 5A). An emergency overflow path must be identified for infiltration facilities and noted on the engineering plan. This overflow path must be analyzed to meet the requirements of Core Requirements #1 (see Section 1.2. 1) and #2 (see Section 1 .2.2) for the 100-year, 24-hour duration design storm, except Downspout Infiltration Systems (see Section 4.5.1 ). Infiltration facilities may be especially useful in the following circumstances, provided the proper soil conditions are present and all requirements can be met. (1) The proposed project discharges to a closed depression. 12) The proposed project discharges to a severely undersized conveyance system that restricts the runoff volume that can be accommodated. (3) The proposed project is in a Critical Drainage Area requiring runoff volume control. Exemptions From On-S~e Peak Rate Runoff Control On-site peak rate runoff control will not be required for a proposed project in the following situations. Negligible Peak Runoff Rate lncrease7 : (1) The proposed project site post-developed peak runoff rate tor the 100-year, 24-hour duration design storm event is calculated for each discharge location 8 to be less than 0.5 cfs more than the peak runoff rate for the existing site corlditions; OR, (2) The project proposes to construct 5,000 square feet, or less, of new impervious surface. Direct Discharge.: The proposed project will discharge surface and storm water .ruooff without on- site peak rate runoff control directly to: · A Regfonal Facility. Direct discharge of surface and stormwater runoff to a regional facility will be allowed if: o the facility has been demonstrated to adequately control the proposed project's increased peak rate of runoff by an adopted King County basin plan or by a detailed drainage analysis approved by the SWM Division; AND o the facility will b~ available by the time of construction of the project; AND o the conveyance system to the regional facility ca.n ac.commodate, with_no significant adverse impact to the drainage systems, the design peak runoff for the proposed project site and the equivalent area' developed to the full zoning potential. 7 Proposed projects in adopted criticar drainage areas, basin plans and community plans requiring peak runoff rate or runoff volume controls more strict than standard controls shall not qualify for this exemption. 6 A threshold discharge area is an on-site area which drains to a single natural discharge location or multiple natural discharge locations that combine within l /4-mile downstream. 9 The eQuivalent area is the area tributary to the receiving water body equal to or less than the shortest, straight line distance from the discharge point from the receiving water body (or regional facility) to the furthermost point of the proposed development. 1 .2 .3-5 ll/94 FIGURE 8 I i ' ' APPENDIXB Conveyance Calculations • COUGHLIN PORTER LUNDEEN Renton School District Transportation Center Conveyance Analysis The method used to analyze the stormwater conveyance capacity for the proposed site development uses the Rational Method to estimate peak flows to the inlets (catch basins, trench drains, etc.) and the Continuity Equation/Manning's Formula to determine the required size of pipe. The continuity equation is shown below: Q=AxV where, Q = flow rate (ft'/ s) A = cross-sectional area of conveyance pipe V = velocity of flow in pipe ( derived from Manning's Formula) Manning's Formula: Manning's equation is used to estimate flows through channels and is based on the assumption of uniform flow, where flow, depth, area of cross-section, velocity of flow, and discharge are the same at every section of the pipe segment. The formula can be derived by equating the propulsive force due to the weight of water in the direction of flow with the retarding shear force at the pipe boundary. This empirical formula is shown below: where, V = 1.486 R 21,8 112 n V = velocity of flow in ft/ s n = roughness coefficient R = hydraulic radius in ft S = slope of pipe Once the velocity of flow is found in the pipe using Manning's Formula, the continuity equation is used to calculate the flow rate. Rational Method: The Rational Method refers to a method of computing peak storm water flows from small urban watersheds. The method is an empirical approach, derived from storm water observations and tests. The basic equation of the rational method has the form: where, QR= peak rate of flow (ft'/s) for storm of return frequency R C = runoff (rational) coefficient IR= Peak rainfall intensity (inches/hour) for a storm of return frequency R A = drainage area (acres) The runoff coefficient, C, is a highly critical element that serves the function of converting the average rainfall rate of a particular recurrence interval to the peak runoff intensity of the same frequency. Therefore, it accounts for many complex phenomena of the runoff process. Its magnitude will be affected by antecedent moisture conditions, ground slope, ground cover, depression storage, soil moistrue, shape of drainage area, overland flow velocity, intensity of rain, and so on. Yet its value is generally considered fixed for any drainage area, depending only on the surface type. Values of the coefficient are given bee low in Table B1. Surface CValue Asphalt Paving 0.7-0.9 Roofs 0.7-0.9 Landscape >7° slope 0.15-0.35 2-7° 0.10-0.22 <2' 0.05-0.17 Forest 0.18 Cultivated Land 0.30 Table Bl: Typical Runoff Coefficients For an area having different type of surfaces, a composite coefficient is determined by estimating the fraction of each type of surface within the total area, multiplying each fraction by the appropriate coefficient of that type of surface, and then summing the products for all types of surfaces. The coefficients are selected so as to reflect the conditions that are expected at the end of the design period. The drainage area, A, represents the drainage are for a site under consideration. For a natural system it represents the watershed. For a storm system network it is the area tributary to a point of inlet. If a system consists of a number of inlets and pipes, the complete are is sub-dived into component parts separating a tributary area to each inlet point of every storm system segment, or pipe. Rainfall intensity, !R, is dependent on the duration of rainfall (short duration storms are more intense) and the storm frequency (or recurrence interval). The peak rainfall intensity IR for the specified design storm of return frequency R is determined using a unit peak rainfall intensity factor iR in the following equation: where, PR= The total precipitation at the project site for the 24-hour duration storm event for the given return frequency, R. IR = The unit peak rainfall intensity factor The unit peak rainfall intensity factor iR is determined by the following equation: where, i = a x (T )-bR R ... R c T, = The travel time of a water particle from the hydraulically most remote point in the sub-basin to the storm system inlet. aR, bR = constants that depend on the frequency and climatic conditions The values for constants aR and bR are obtained using observed rainfall data for the locality selected. See table B2 below for frequency levels of 2, 5, 10, 25, 50, and 100 years for values typical of the King County region. Design Storm Return Frequencv aR bR 2 year 1.58 0.58 5year 2.33 0.63 10 year 2.44 0.64 25 year 2.66 0.65 50year 2.75 0.65 100 year 2.61 0.63 .. Table B2: Coefficients for the Rational Method "1R" equation The "ii' equation is based on the original Renton/Seattle Intensity /Duration/Frequency (IDF) curves. The rainfall intensity-duration-frequency (IDF) relation for a gauging site is developed from the data of a recording rain gage. Since the point rainfalls or observations at a gauging site are considered representative of a larger area, the above IDF analysis is representative of only the King County region. Time of concentration, T,, is defined as the time required for runoff from the hydraulically most remote part of the drainage area to reach the point of reference (or inlet). Since rainfall intensity reduces with increase in storm duration, the duration should be as short as possible. However, if the rainfall duration is less then T,, then only a part of the drainage area will be contributing to the runoff. For an entire area to contribute, the shortest storm duration should equal T,. Thus the time of concentration is used as a unit duration for which rainfall intensity is determined. In storm system design, in addition to the time required for the rain falling on the most remote point of the tributary area to flow across the ground surface, along streets, and gutters, to the point of entry into the storm system, the time of flow through the sewer line is also important. The surface runoff and subsurface storm pipe flow times are added together when computing the capacity for the downstream system. Due to the mathematical limits of the peak rainfall intensity equation coefficients, values of T, less than 6.3 minutes or greater then 100 minutes cannot be used. Therefore, real values of T, less than 6.3 minutes must be assumed to be equal to 6.3 minutes, and values greater than 100 minutes must be assumed to be equal to 100 minutes. See the following tables tabulating the conveyance characteristics for the proposed onsite storm system for both the 25-year, 24--hour storm and the 100-year, 24--hour storm . • Renton School District Transit Center Draina e Suh-Basin Areas Sub· Total Composite Asphalt/Concrete Roof Grass Basil Area1 C Value Area Area Arca (Acres) (Sq. H), C=0.90 (Sq. Ft.), C=0.90 (Sq. Fl), Caa/1.25 CB 13 o.n. 0.78 5813 0 1376 CB 12 0.37 . 0.48 2683 3102 10448 CB 11 0.47 · o:s9 6051 14103 376 CHIO '0.20 0.87 8109 0 411 CB8 0.16 :ow 6907 0 0 CB7 0-14 .. 0.90 6215 0 0 CB 6c 0.13 0.90 5638 0 0 CB6b {).66 0.87 27306 0 1403 CB6a 0,90 27534 0 0 CB6 0.00 0 0 0 CB5 o:s9 29339 0 528 CB4b 0.90 10692 0 0 CB4a 0.87 10582 0 600 CB4 0.0() o.oo 0 0 0 CBJ ·o.oo 0:00 0 0 0 CB2 : 0.00 0.00 0 0 0 CB9a 0.30 . 0.85 11986 0 1050 CB9 0.00 Q:00 0 0 0 CBI . 0.00 · 0.00 0 0 0 EXCB o.oo o.oo 0 0 0 Totals 1 4.41 158855 1.7205 16192 Notes: 1These sub.basin areas are based on developed site conditions. 2 Additional landscaping area from the perimeter of the site flows to street conveyance system. 3 Landscaping areas to the west and south of the building in basin 12 will be collected through area drains that will be included in the permit submittal. Renton School District Transit Center Conveyance Analysis 9/27/2007 0 C C 0 0 TI C 0 ~ c,i 0 0 N COUGHLIN PORTERLUNDEEN A CONSUL TING STRUCTURAL AND CIVIL ENGINEERING CORPORATION .1 CB a--1 -I ... _I ~···· 3t!L.Street .. ---I ~--=--.-.::....,.. __ I ~PR=OJ=EC~T: __ ~RE=NT=O~N. SCHOOL DISTRICT TRANSIT CENTER DESIGNED BY: CMP DATE: 10.03.07 ---- PROJECT NO. CQ6.Q055·02 ~---CHECKED BY: TBB SITE SUBBASINS 413 PINE STREET -SUITE 300 SEATTLE, WA 98101 P: 206/343-0460 F: 206/343-5691 CONVEYANCE SYSTEM ANALYSIS AND SIZING TABLE USING IBE RATIONAL METHOD Sub Area C C*A Sum Tc i(R) I(R) Q(R) Pipe Typ. Slope Q(F) V V L Tt %d/D Basin (ac) C*A (min.) (c.fa.) (in.) 11 (ft.ft.) (pipe (pipe (at (ft.) (min.) From To Number •· full) full) Q(R)) CB13 CB 12 CB13 0.17 0.78 0.13 0.13 6.3 0.80 2.49 ,·. 0.32 12 0.013 1.00% 3.57 4.55 2.85 112 0.7 20.00% CB 12 en 11 CB 12 0.37 0.48 0.18 0.31 7.0 0.75 2.34 0.72 12 0.013 1.00% 3.57 4.55 3.63 64 0.3 30.00% CB II CB 10 CB 11 0.47 0.89 0.42 0.73 7.2 0.73 2.28 1.65 12 0.013 1.00% 3.57 4.55 4.43 164 0.6 48.00% CB 10 CB9 CB 10 0.20 0.87 0.17 0.90 7.9 0.70 2.16 1.93 12 0.013 1.00% 3.57 4.55 4.57 76 0.3 53.00% ' ··. CB 9a CB9 CB 9a 0.30 0.85 0.25 0.25 6.3 0.80 2.49 0.63 8 0.013 15.50% 4.77 13.67 9.82 7 0.0 24.00% ••• ,,, CB9 CB 1 CB9 0.00 0.00 0.00 1.15 8.1 0.68 2.11 2.43 · 12 0.013 1.00% 3.57 4.55 4.88 32 0.1 60.50% ' ,,, CBS CB7 CB8 0.16 0.90 0.14 0.14 6.3 0.80 2.49 0.36 8 0.013 0.50% 0.86 2.46 2.33 77 0.5 45.00% CB7 CB6 CB 7 0.14 0.90 0.13 0.27 6.8 0.76 2.36 0.64 8 0.013 0.50% 0.86 2.46 2.71 211 1.3 64.00% CB6c CB6 CB6c 0.13 0.90 0.12 0.12 6.3 0.80 2.49 0.29 8 0.013 2.30% 1.84 5.27 3.82 43 0.2 27.00% ,', CB6b CB6 CB6b 0.66 0.87 0.57 0.57 6.3 0.80 2.49 . 1.43 8 0.013 2.30% 1.84 5.27 5.84 49 0.1 66.00% ,,' CB 6a CB6 en 6a 0.63 0.90 0.57 0.57 6.3 0.80 2.49 1.42 8 0.013 4.60% 2.60 7.45 7.46 39 0.1 53.50% '' CB6 CBS CB6 0.00 0.00 0.00 1.53 8. l 0.68 2.11 3.22 12 0.013 1.00% 3.57 4.55 5.17 224 0.7 74.00% CBS Cn4 CBS 0.69 0.89 0.61 2.14 8.9 0.64 2.00 · 4.27 18 0.013 1.00% 10.53 5.96 5.53 151 0.5 45.00% CB4b CB4a CB4b 0.25 0.90 0.22 0.22 6.3 0.80 2.49 0.55 8 0.013 1.00% 1.21 3.47 3.32 84 0.4 48.00% CB4a CB4 CB4a 0.26 0.87 0.22 0.44 6.7 0.77 2.39 1.06 8 0.013 5.10% 2.74 7.85 7.16 40.0 0.1 44.00% ,-,"',, CB4 CB3 CB4 0.00 0.00 0.00 2.58 9.3 0.62 1.93 4.99 18 0.013 1.00% 10.53 5.96 5.79 36 0.1 49.00% CB3 cn2 CB3 0.00 0.00 0.00 2.58 9.4 0.62 1.92 . 4.95 18 0.013 1.00% 10.53 5.96 5.75 44 0.1 49.00% CB2 CB I CB 2 0.00 0.00 0.00 2.58 9.6 0.61 1.90 4.91 18 0.013 1.00% 10.53 5.96 5.70 32 0.1 49.00% CB I EXCB CB I 0.00 0.00 0.00 3.73 9.6 0.61 1.89 7.05 18 0.013 1.00% 10.53 5.96 6.37 29 0.1 60.00% •· ' ' • ' ' ' ' • ' -Project: Renton School District Transit Center R~ ~ P(R)~ .llJ) Cales by: CMP Job No: C06-0055-02 Location: King County, WA Date• 9/27/2007 Page l Renton School District Transit Center Conveyance Analysis -25 Year 9/27/2007 Employee Parking Water Quality Flows for EcoStorm Dev.pks Flow Frequency Analysis LogPearson III coefficients Time Series File:dev.tsf Mean= -0.207 stdDev= 0.146 Project Location:sea-Tac Skew= 1.189 ---Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks --Rank Return Prob (CFS) (CFS) Period 0.788 8 2/16/ 49 17: 45 2.00 1 89. 50 0.989 1.03 6 8/15/50 6:45 1. 32 2 32.13 0.969 0.557 31 8/27 /51 18: 00 1.22 3 19. 58 0.949 0. 585 25 10/17/51 7:15 1.07 4 14.08 0.929 0.452 42 9/30/53 3:00 1.05 5 10.99 0.909 0.481 38 12/19/53 17:30 1.03 6 9.01 0.889 0.454 41 7/30/55 21:15 0.801 7 7.64 0.869 0.684 17 10/04/55 10: 00 0.788 8 6.63 0.849 0.554 32 10/19/56 23: 45 0.772 9 5.86 0.829 0. 524 36 1/16/58 10: OD 0.766 10 5.24 0.809 0. 724 12 10/18/58 19: 45 0.739 11 4.75 0.789 0.685 16 10/10/59 22: 00 0. 724 12 4.34 0.769 0.561 29 2/14/61 20:15 0.719 13 3.99 0.749 0.549 33 8/04/62 13: 15 0.719 14 3.70 0.729 0.478 39 12/01/62 20:15 0.710 15 3.44 0.709 0.412 47 6/05/64 15:00 0.685 16 3.22 0.690 o. 511 37 4/20/65 19:30 0.684 17 3.03 0.670 0.391 49 9/17/66 17:45 0.674 18 2 .85 0.650 0.622 22 11/13/66 17: 45 0.652 19 2.70 0.630 1. 22 3 8/24/68 15:00 0.648 20 2.56 0.610 o. 570 28 10/20/68 12:00 0.637 21 2.44 o. 590 0. 357 50 5/29/70 7:45 0.622 22 2.32 0.570 0.410 48 12/06/70 7:00 0.607 23 2.22 o. 550 0.801 7 12/08/7117:15 0.605 24 2.13 o. 530 0. 532 35 4/18/73 9:30 0.585 25 2.04 0.510 0. 579 26 11/28/73 8:00 0.579 26 1.96 0.490 0.710 15 8/17 /75 23: 00 0. 577 27 1.89 0.470 0.433 46 10/29/75 7:00 0. 570 28 1.82 0.450 0.446 44 8/23/77 14: 30 o. 561 29 1. 75 0.430 0. 766 10 9/17/78 1:00 0.559 30 1. 70 0.410 1.07 4 9/08/79 13: 45 0.557 31 1.64 0.390 0.648 20 12/14/79 20:00 0.554 32 1. 59 o. 370 0.739 11 9/21/81 8:00 0. 549 33 1.54 0.350 1. 32 2 10/05/81 22: 15 0. 537 34 1.49 0.330 0.605 24 10/28/82 16:00 0. 532 35 1. 45 0.310 0.458 40 1/02/84 23:30 0. 524 36 1.41 0.291 0.441 45 6/06/85 19:15 0. 511 37 1. 37 0.271 0.637 21 10/27/85 10:45 0.481 38 1.33 0.251 0. 772 9 10/25/86 22: 45 0.478 39 1.30 0.231 0.652 19 5/13/88 17: 30 0.458 40 1.27 0.211 0.607 23 8/21/89 16:00 0.454 41 1.24 0.191 0 .719 14 1/09/90 5:00 0.452 42 1. 21 0.171 0.559 30 4/03/91 20:15 0.449 43 1.18 0.151 0.449 43 1/27/92 15:00 0.446 44 1.15 0.131 0. 537 34 6/09/93 12: 15 0.441 45 1.12 0.111 o. 577 27 11/17 /93 16: 45 ~ 0.433 46 1.10 0.091 0.674 18 6/05/95 17:00 0.412 47 1.08 0.071 0. 719 13 7 /19/96 19: 30 0.410 48 1.05 0.051 2.00 1 12/29/96 11:45 0.391 49 1.03 0.031 1.05 5 10/04/97 14: 15 0.357 50 1.01 0.011 computed Peaks 1.78 100.00 0.990 Computed Peaks 1.50 50.00 0.980 computed Peaks 1.25 25.00 0.960 computed Peaks 0.974 10.00 0.900 computed Peaks 0.926 8.00 0.875 computed Peaks 0.795 5.00 0.800 Page 1 Page 1 of 2 Employee Parking Water Quality Flows for EcoStorm computed Peaks Computed Peaks ~ ~ 2.00 0.500 1.30 0.231 Water Quality Flow= 0.582 x 60% 0.35 cfs Page 2 Page 2 of 2 Bus Parking Water Quality Flows for EcoStorm and Oil Water Separator Dev.pks Flow Frequency Analysis LogPearson III coefficients Time series File:dev.tsf Mean= 0.168 StdDeV= 0.144 Project Location:sea-Tac skew= 1.158 ---Annual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks Rank Return Prob (CFS) (CFS) Period 1. 85 8 2/16/49 17:45 4.61 1 89.50 0.989 2.44 6 8/15/50 6:45 3.08 2 32.13 0.969 1. 33 29 8/27/51 18:00 2.87 3 19.58 0.949 1.38 25 10/17 /51 7: 15 2.54 4 14.08 0.929 1.08 42 9/30/53 3:00 2.44 5 10.99 0.909 1.14 38 12/19/53 17: 30 2.44 6 9.01 0.889 1.09 40 7 /30/55 21: 15 1. 87 7 7.64 0.869 1.64 16 10/04/55 10:00 1. 85 8 6.63 0.849 1.31 33 10/19/56 23: 45 1.84 9 5.86 0.829 1.23 36 1/16/58 10:00 1.83 10 5.24 0.809 1.72 12 10/18/58 19:45 1. 77 11 4.75 0.789 1.62 17 10/10/ 59 22: 00 1. 72 12 4.34 o. 769 1. 32 30 2/14/61 20: 15 1. 72 13 3.99 0.749 1. 32 31 8/04/62 13: 15 1. 70 14 3.70 0.729 1.13 39 12/01/62 20: 15 1. 68 15 3.44 0.709 0.986 47 6/05/64 15: 00 1. 64 16 3.22 0.690 1.20 37 4/20/65 19: 30 1. 62 17 3.03 0.670 0.936 49 9/17/66 17:45 1.61 18 2.85 0.650 1.46 22 11/13/66 17: 45 1. 56 19 2.70 0.630 2.87 3 8/24/68 15:00 1. 52 20 2.56 0.610 1. 35 28 10/20/68 12:00 1. 51 21 2.44 0.590 0.855 so 5/29/70 7:45 1.46 22 2.32 0. 570 0.970 48 12/06/70 7:00 1. 45 23 2.22 0. 550 1.87 7 12/08/7117:15 1.43 24 2.13 0. 530 1.27 34 4/18/73 9: 30 1. 38 25 2.04 0. 510 1.36 27 11/28/73 8:00 1. 38 26 1.96 0.490 1.70 14 8/17/75 23:00 1. 36 27 1.89 0.470 1.02 46 10/29/75 7:00 1. 35 28 1.82 0.450 1.07 43 8/23/77 14: 30 1. 33 29 1. 75 0.430 1.83 10 9/17/78 1:00 1. 32 30 1. 70 0.410 2.54 4 9/08/79 13:45 1. 32 31 1.64 0.390 1. 52 20 12/14/79 20:00 1. 32 32 1. 59 0.370 1. 77 11 9/21/81 8:00 1. 31 33 1. 54 0.350 3.08 2 10/05/81 22:15 1.27 34 1.49 0.330 1.43 24 10/28/82 16:00 1.26 35 1.45 0.310 1.09 41 1/02/84 23: 30 1. 23 36 1.41 0.291 1.05 45 6/06/85 19:15 1. 20 37 1. 37 0.271 1.51 21 10/27/85 10:45 1.14 38 1.33 0.251 1.84 9 10/25/86 22:45 1.13 39 1. 30 0.231 1.56 19 5/13/88 17: 30 1.09 40 1.27 0.211 1.45 23 8/21/89 16: 00 . 1.09 41 1.24 0.191 1.68 15 11/03/89 23:45 1.08 42 1.21 0.171 1. 32 32 4/03/91 20: 15 1.07 43 1.18 0.151 1.06 44 1/27 /92 15: 00 1.06 44 1.15 0.131 1.26 35 6/09/93 12:15 1.05 45 1.12 0.111 1.38 26 11/17/93 16:45 1.02 46 1.10 0.091 1.61 18 6/05/95 17:00 0.986 47 1.08 0.071 1. 72 13 7 /19/96 19: 30 0.970 48 1.05 0.051 4.61 1 12/29/96 11:45 0.936 49 1.03 0.031 2.44 5 10/04/97 14:15 0.855 50 1.01 0.011 computed Peaks 4.14 100.00 0.990 computed Peaks 3.50 50.00 0.980 Computed Peaks 2.93 25.00 0.960 computed Peaks 2.30 10.00 0.900 computed Peaks 2.18 8.00 0.875 computed Peaks 1. 88 5.00 0.800 Page 1 Page 1 of 2 computed Peaks computed Peaks Bus Parking Water Quality Flows for EcoStorm and Oil Water Separator De~ Q,_JJV 1.14 2.00 0. 500 1.30 0.231 Water Quality Flow= 1.38 x 60% 0.83 cfs Page 2 Page 2 of 2 APPEND!XC Geotechnical Report COUGHLIN PORTER LUNDEEN Renton School District Transporta lion Center Geotechnical Engineering -,," ... ::._~~ Water Resources Associated Earth Sciences, Inc. C8~lrtloy .zy ~tln' q/Jero'c8 Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report NEW TRANSPORTATION CENTER Environmental Assessments and Remediation Sustainable Development Services Geologic Assessments Renton, Washington Prepared for Renton School District No. 403 Project No. KE070040A June 14, 2007 I I I I I I I I I I I I I I I I I I I I I Associated Earth Sciences, Inc. ~4)~~~ ~ L4J--"'-~ ~ ~ June 14, 2007 Project No. KE070040A Renton School District No. 403 Capital Projects Office 1220 North 4th Street Renton, Washington 98055 Cek6ra£in_J 2!j 1f ears of.-S'e!Vice Attention: Mr. Stewart L. Shusterman Subject: Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report New Transportation Center 1220 North 4•h Street Renton, Washington Dear Mr. Shusterman: We are pleased to present the enclosed copies of the above-referenced report. This report summarizes the results of our subsurface exploration, geologic hazard, and geotechnical engineering studies and offers recommendations for the design and development of the proposed project. The report revision reflects the alternate foundation and floor support options proposed during the value engineering process. We have enjoyed working with you on this study and are confident that the recommendations presented in this report will aid in the successful completion of your project. If you should have any questions or if we can be of additional help to you, please do not hesitate to call. Sincerely, ASSOCIATED EARTH SCIENCES, INC. Kirkland, Washington =b ... ,' Kurt D. Merriman, P.E. Principal Engineer KDM/ld • KE070040A4 -Projects\20070040\KE\WP Kirl<land Office' 911 Fifth Avenue, Suite 100' Kirl<land, WA 98033 • P J (425) 827-7701 • F J (425) 827-5424 Everett Office' 2911 112 HewittAvenue, Suitel • Everett, WA 98201 •PI (425) 259-0522 •FI (425) 252-3408 vvww.aesgeo.com REVISED SUBSURFACE EXPLORATION, GEOLOGIC 1-IAZARD, AND GEOTECHNICAL ENGINEERING REPORT NEW TRANSPORTATION CENTER Renton, Washington Prepared for: Renton School District No. 403 Capital Projects Office 1220 North 4'h Street Renton, Washington 98055 Prepared by: Associated Earth Sciences, Inc. 911 5<h A venue, Suite 100 Kirkland, Washington 98033 425-827-7701 Fax: 425-827-5424 June 14, 2007 Project No. KE070040A New Transponation Cenrer Renton, Washington 1.0 INTRODUCTION Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report Project and Site Conditions I. PROJECT AND SITE CONDITIONS This report presents the results of our revised subsurface exploration, geologic hazard, and geotechnical engineering study for the proposed New Transportation Center to be located at 1220 North 4th Street in Renton, Washington. The report revision reflects the alternate foundation and floor support options proposed during the value engineering process. The site location is presented on Figure 1, "Vicinity Map." The proposed building location and approximate locations of the explorations accomplished for this study are presented on the "Site and Exploration Plan," Figure 2. In the event that any changes in the nature, design, or location of the structure are planned, the conclusions and recommendations contained in this report should be reviewed and modified, or verified, as necessary. 1.1 Purpose and Scope The purpose of this study was to provide subsurface data to be utilized in the design and development of the aforementioned project. The study included drilling six test borings and performing geologic studies to assess the type, thickness, distribution, and physical properties of the subsurface sediments and ground water conditions. Geologic hazard evaluations and engineering studies were also conducted to determine suitable geologic hazard mitigation techniques, the type of suitable pile foundation, pile design recommendations, anticipated settlements, floor support recommendations, and site preparation and drainage considerations. This report summarizes our current fieldwork and offers geologic hazard mitigation and development recommendations based on our present understanding of the project. 1.2 Authorization Written authorization to proceed with this study was granted by Mr. Stewart Shusterman of the Renton School District No. 403 (District). Our study was accomplished in general accordance with our scope of work letter dated January 23, 2007. This report has been prepared for the exclusive use of the District and their agents for specific application to this project. Within the limitations of scope, schedule, and budget, our services have been performed in accordance with generally accepted geotechnical engin;ering and engineering geology practices in effect in this area at the time our report was prepared. Our observations, findings, and opinions are a means to identify and reduce the inherent risks to the owner. No other warranty, express or implied, is made. June 14, 2007 A SSOCJATED EARTH SCJENCES, INC. SGB/ld-KE07D040A4 -ProjecJs\2{X)70040\KElWP Page 1 New Transportation Center Renton, Washington 2.0 PROJECT AND SITE DESCRIPTION Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Proiect and Site Conditions This report was completed with an understanding of the project based on a preliminary building layout and site plan provided by the District. The project site is the existing District transportation center. The site is located at 1220 North 4"' Street in downtown Renton, Washington. The existing property includes a large warehouse building at the southeast corner with a two-story office building to the northwest of the warehouse. A third small building is located near the north end of the property. The remainder of the site is either surfaced with gravel or asphalt, which is in poor condition. The paved areas are primarily used for bus parking. The gravel parking area to the west of the office building is used for employee parking. We understand that present plans call for demolishing existing buildings and constructing a new lightly loaded administrative building near the west-central portion of the site. The existing gravel parking area near the north end of the site and drive/parking areas surrounding the new building will also be paved. The new building footprint will encompass approximately 18,000 square feet. We have not been provided with a grading plan or any details on the building construction or loading conditions. Therefore, we have assumed that site grades will remain close to present grades and that the new structure will be a two-story, wood-framed building with light to moderate foundation loads. 3.0 SUBSURFACE EXPLORATION Our field study included drilling six exploration borings with a truck-mounted drill rig to gain subsurface information about the site, and collecting soil samples. The various types of sediments, as well as the depths where characteristics of the sediments changed, are indicated on the exploration logs presented in the Appendix to this report. The depths indicated on the boring Jogs where conditions changed may represent gradational variations between sediment types in the field. If changes occurred between sample intervals in our borings, they were interpreted. Our explorations were· approximately located in the field by measuring from known site features shown on an aerial photograph of the site with tbe proposed building location overlain on the photograph. ~ The conclusions and recommendations presented in this report are based on the six explorations completed for this study. The number, type, locations, and depths of the explorations were completed within site and budgetary constraints. Because of the nature of exploratory work below ground, extrapolation of subsurface conditions between field explorations is necessary. It should be noted that differing subsurface conditions are sometimes present due to the random nature of deposition and the alteration of topography by June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB!ld-KE07004DA4-Projecls\2007004()\kEIWP Page 2 New Transportation Center Renton. Washington Revised Subswface Exploration, Geologic Hazard, and Geolechnical Engineering Repon Project and Site Conditions past grading and/or filling. The nature and extent of any variations between the field explorations may not become fully evident until construction. If variations are observed at that time, it may be necessary to re-evaluate specific recommendations in this report and make appropriate changes. 3 .1 Exploration Borings The exploration borings were completed by advancing a 33/a-inch, inside-diameter, hollow- stem auger with a truck-mounted drill rig to depths ranging from 45 to 95 feet. Below the water table, the borings were successfully completed with little or no heaving conditions with water stabilization drilling techniques. During the drilling process, samples were obtained at generally 5-foot-depth intervals. The borings were continuously observed and logged by a geotechnical engineer or engineering geologist from our firm. The exploration logs presented in the Appendix are based on the field logs, drilling action, and inspection of the samples secured. Disturbed, but representative samples were obtained by using the Standard Penetration Test procedure in accordance with American Society for Testing and Materials (ASTM):D 1586. This test and sampling method consists of driving a standard 2-inch, outside-diameter, split- barrel sampler a distance of 18 inches into the soil with a 140-pound hammer free-falling a distance of 30 inches. The number of blows for each 6-inch interval is recorded, and the number of blows required to drive the sampler the final 12 inches is known as the Standard Penetration Resistance ("N") or blow count. If a total of 50 is recorded within one 6-inch interval, the blow count is recorded as the number of blows for the corresponding number of inches of penetration. The resistance, or N-value, provides a measure of the relative density of granular soils or the relative consistency of cohesive soils; these values are plotted on the attached boring logs. The samples obtained from the split-barrel sampler were classified in the field and representative portions placed in watertight containers. The samples were then transported to our laboratory for further visual class.ification and laboratory testing, as necessary. 3.2 Laboratory Tests ~ We performed percent passing the No. 200 sieve analysis by ASTM Method D 1140 on all samples collected from exploration boring EB-I for liquefaction hazard analysis. The results of these tests are presented in the Appendix following the exploration logs. June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB/ld -KE070040A4-Projew\200700401K£\WP Page 3 New Transporlation Center Renton, Washington 4.0 SUBSURFACE CONDITIONS Revised Subswface Exploraiion, Geologic Hazard, and Geoteclznical Engineering Report Project and Site Conditions The encountered soils were consistent with the geology mapped in the site area, as shown on the Geologic Map of King County, Washington by Booth et al., 2002. This map shows the site area is mantled by Quaternary alluvium deposited by the ancestral Cedar River. 4 .1 Stratigraphy Fill Man-placed fill, consisting of silty sand with gravel, was encountered in all explorations to depths of roughly 3 feet. The fill and the upper surface of the underlying alluvium are in a loose to medium dense condition. Quaternary Alluvium Sediments encountered beneath the asphalt and fill generally consisted of interbedded clean sand, silty sand, clayey and lean silt with occasional lenses of gravel, peat, and other organics scattered throughout the soil column. We interpret these sediments to be representative of recent and older alluvium deposited in former channels of the Cedar River. The alluvium extends beyond the depth of our deepest exploration (95 feet). In general, the alluvium is very loose/soft to medium dense to an average depth of about 75 feet throughout the building pad area. Below roughly 75 feet, the alluvium occurs in a dense condition and is relatively more granular. Conditions encountered in exploration boring EB-I were anomalous relative to the other explorations, as dense sediments were encountered at much shallower depths. The saturated soil in which "N" values do not exceed roughly 25 has a high potential for liquefaction-induced settlement. In addition, the abundant layers of very soft clayey and lean silt are subject to consolidation settlement under the new building loads. Therefore, structures will require deep pile foundations for support. In general, the soil where moisture content is within the compactable range is considered suitable for reuse as structural fill. It should be noted that where soils are above their optimum moisture content for compaction, their reuse as structural fill during all but the driest times of the year will be difficult. Existing alluvia.) soil was observed to contain silt and is considered moisture-sensitive. With appropriate remedial treatment, the soil, where moisture content is within the compactable range, may be considered suitable for support of slab-on-grade floors, hardscape, and paving. June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB!ld-KE07004(),44. Projec1sl20070040\KE\WP Page 4 New Transponation Center Renton, Washington 4.2 Hydrology Revised Subswface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Proiect and Site Conditions Ground water was encountered at an average depth of 10 feet across the site corresponding roughly to Elevation 25 feet. However, ground water depths reported during drilling may not represent stabilized ground water elevations that would be recorded in a properly constructed monitoring well. Ground water encountered in our explorations represents the regional un- confined ground water aquifer within the Renton basin. Ground water may be encountered in excavations that penetrate into the underlying alluvial soils. To our knowledge, no deep cuts are planned that will intersect the regional ground water aquifer. If such cuts will be made, significant ground water dewatering operations will be necessary. It should be noted that fluctuations in the level of the ground water may occur due to the time of the year, variations in rainfall, and adjacent river levels. June 14, 2007 ASSOC/A TED EARTH SCIENCES, INC. SGB!ld -KE070040A4 -Projecls\20070040\KE\WP Page 5 New Transponation Center Renton, Washington Revised Subsuiface Exploration, Geologic Hazard, and Geotechnica/ Engineering Report Geolo&ic Hazards and Mitigations II. GEOLOGIC HAZARDS AND MITIGATIONS The following discussion of potential geologic hazards is based on the geologic, slope, and ground water conditions as observed and discussed herein. The discussion will be limited to seismic, landslide, and erosion hazards, including sediment transport. 5.0 SLOPE STABILITY HAZARDS AND RECOMMENDED MITIGATION Reconnaissance of this site was limited to the area shown on Figure 2. The site topography is relatively flat, and therefore the risk of landsliding is low. 6.0 SEISMIC HAZARDS AND RECOMMENDED MITIGATION Earthquakes occur in the Puget Sound Lowland with great regnlarity. Most of these events are small and are usually not felt by people. However, large earthquakes do occur, as evidenced by the most recent 6.8-magnitude event on February 28, 2001 near Olympia Washington; the 1965, 6.5-magnitude event; and the 1949, 7.2-magnitude event. The 1949 earthquake appears to have been the largest in this area during recorded history. Evaluation of return rates indicates that an earthquake of the magnitude between 5.5 and 6.0 is likely within a given 20-year period. Generally, there are four types of potential geologic hazards associated with large seismic events: I) surficial ground rupture, 2) seismically induced landslides, 3) liquefaction, and 4) ground motion. The potential for each of these hazards to adversely impact the proposed project is discussed below. 6.1 Surficial Ground Rupture The nearest known fault trace to the project site is the Seattle Fault, located approximately 5 miles to the north. Recent studies by the U.S. Geological Survey (USGS; e.g., Johnson et al., 1994, Origin and Evolution of the SeaJtle Fault and Seattle Basin, Washington, Geology, v. 22, pp. 71-74; and Johnson et al., 1999, Active Tectonics of the Seattle Fault and Central Puget Sound Washington -Implications for Earthquake Hazards, Geological Society of America Bulletin, July 1999, v. 111, n. 7, pp. 1042-1053) have provided evidence of surficial ground rupture along a northern splay of the Seattle Fault. The recognition of this fault splay is relatively new, and data pertaining to it are limited, with the studies still ongoing. According to the USGS studies, the latest movement of this fault was about 1,100 years ago JU/le 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGBl/d -KE070040A4 -Projec/5\200700401KE\WP Page 6 New Transportation Center Renton, Washingwn Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Gf!ologic Hazards and Mitigations when about 20 feet of surficial displacement took place. This displacement can presently be seen in the form of raised, wave-cut beach terraces along Alki Point in West Seattle and Restoration Point at the south end of Bainbridge Island. The recurrence interval of movement along this fault system is still unknown, although it is hypothesized to be in excess of several thousand years. Due to the suspected long recurrence interval and depth of loose/soft alluvium present within the site boundaries, the potential for surficial ground rupture is considered to be low during the expected life of the proposed structure. 6.2 Seismically Induced Landslides Reconnaissance of this site was limited to the area shown on Figure 2. The site topography is relatively flat to gently sloping, and therefore the risk of landsliding is low. 6. 3 Liquefaction We performed a liquefaction hazard analysis for this site in accordance with guidelines published in Seed & Idriss, 1982; Seed et. al, 1985; and Kraruer, 1996. Our liquefaction analysis was completed with the aid of LiquefyPro computer software Version 4.3 by CivilTech Corporation. Liquefaction occurs when vibration or ground shaking associated with moderate to large earthquakes (generally in excess of Richter magnitude 6) results in loss of internal strength in certain types of soil deposits. These deposits generally consist of loose to medium dense sand or silty sand that is saturated (e.g., below the water table). Loss of soil strength can result in consolidation and/or lateral spreading of the affected deposit with accompanying surface subsidence and/or heaving. The liquefaction potential is dependent on several site-specific factors, such as soil grain size, density (modified to standardize field-obtained values), site geometry, static stresses, level of ground acceleration considered, and duration of the event. The earthquake pararueters (a magnitude 7 .5 earthquake occurring directly beneath the site with a peak horizontal ground acceleration of 0.34g) used in our liquefaction analysis are in accordance with the required pararueters set forth in the 2003 Iruernational Building Code (IBC). This level of acceleration is significantly greater than previously required by the Uniform Building Code (UBC). Figure 3 models the soil column, as identified in exploration boring EB-3, with a maximum ground water table of 7 feet during a design-level event. Figure 4 models the composite soil column, as identified in EB-3 and EB-4, with a maximum ground water table of 7 feet during a design-level event. Our analysis indicates that the site soils have a high risk of liquefaction above a depth of 32 feet in EB-3 and above a depth of 75 feet in EB-4 and EB-5. Conditions in EB-6 are similar to EB-4 and EB-5. Potential settlements ranging from roughly 10 to 29 inches were calculated for the site soil profile during a design-level event. It should be understood that June I 4, 2007 ASSOCIATED EARTH SCIENCES. INC. SGBl/d -KE070040A4 -Projwsl200700401KE\ WP Page 7 New Transponacion Center Renton, Washington Revised Subswface Exploration, Geologic Ha:z.ard, and Geotechnical Engineering Repon Geologic Hazards and Mitigations several soil properties used in the liquefaction analysis are estimated based on published data and engineering judgment. Therefore, these settlement estimates should be considered approximate and "worst-case scenarios." In addition to liquefaction settlement, the site soils are also subject to consolidation settlement under the new static building foundation loads (independent of seismic shaking). Therefore, we recommend that all building elements, including floor slabs and other structures, be supported on pile foundations. However, if the owner can assume the risk of potential liquefaction-induced settlements of this magnitude, the floor slab could be supported as a floating slab-on-grade. Pile foundations that extend to the minimum depths described in the "Design Recommendations" section of this report should reduce both consolidation settlement and seismically induced structure settlement to tolerable levels for new construction. Partial mitigation of the liquefaction risk could be provided by the use of a structurally reinforced mat foundation. The mat foundation would be subject to total and differential settlements that are considered greater than acceptable. The mat foundation would act as a "raft" below the structure to help reduce structural damage. Post-earthquake re-leveling may or may not be possible or practical, based on the settlement experience. A mat foundation will not mitigate consolidation settlement. We are available to provide more input on a mat foundation system, if requested. 6.4 Ground Motion Guidelines presented in the 2003 IBC should be used for structural design. Based on the exploration borings performed at the site, we interpret the subsurface conditions to correspond to a Site Class "F", as defined by Table 1615.1.1 of the 2003 IBC. Site Class "F" would apply to the site due to the potential for liquefiable soils. However, we anticipate that the period of vibration of the structure will be less than 0.5 second, which should be confirmed by the structural engineer. Therefore, we recommend using a Site Class "E" per Note b in Tables 1615.1.2(1) and 1615.1.2(2) of the 2003 IBC. The 2003 IBC seismic design parameters for short period (Ss) and I-second period (S1) spectral acceleration values were determined by the latitude and longitude of the project site using the USGS National Seismic Hazard Mapping Project website 1. Based on the more current 2002 data, the USGS website interpolated ground motions at the project site to be 1.43g and 0.49g for building periods of 0.2 and 1.0 seconds, respectively, with a 2 percent chance of exceedence in 50 years. 7.0 EROSION HAZARDS AND RECOMMENDED MITIGATION As of October 1, 2006, the Washington State Department of Ecology (Ecology) Construction Storm Water General Permit (also known as the National Pollutant Discharge Elimination 1 http://eqdesign.cr. usgs.gov June 14, 2007 SGBl/d.. KE070040A4-Projwsl20070040\K£1WP ASSOCIATED EARTH SCIENCES. INC Page 8 New Transponation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Repo,1 Geologic Hazards and Mitigations System [NPD ES] permit) requires weekly Temporary Erosion and Sedimentation Control (TESC) inspections for all sites 1 or more acres in size that discharge storm water to surface waters of the state. The TESC inspections must be completed by a Certified Erosion and Sediment Control Lead (CESCL) for the duration of the construction. TESC reports do not need to be sent to Ecology, but should be logged into the project Storm Water Pollution Prevention Plan (SWPPP). If the project does not require a SWPPP, the TESC reports should be kept in a file on-site, or by the permit holder if there is no facility on-site. Ecology also requires weekly turbidity monitoring by a CESCL of storm water leaving a site for all sites 5 acres or greater. Ecology requires a monthly summary report of the turbidity monitoring results (if performed) signed by the NPDES permit holder. If the monitored turbidity equals or exceeds 25 nephelometric turbidity units (NTU) (Ecology benchmark standard), the project best management practices (BMPs) should be modified to decrease the turbidity of storm water leaving the site. Changes and upgrades to the BMPs should be continued until the weekly turbidity reading is 25 NTU or lower. If the monitored turbidity exceeds 250 NTU, the results must be reported to Ecology within 24 hours and corrective action taken. Daily turbidity monitoring is continued until the corrective action Jowers the turbidity to below 25 NTU. In order to meet the current Ecology requirements, a properly developed, constructed, and maintained erosion control plan consistent with the City of Renton standards and best management erosion control practices will be required for this project. Associated Earth Sciences, Inc. (AES!) is available to assist the project civil engineer in developing site-specific erosion control plans. Based on past experience, it will be necessary to make adjustments and provide additional measures to the TESC plan in order to optimize its effectiveness. Ultimately, the success of the TESC plan depends on a proactive approach to project planning and contractor implementation and maintenance. The erosion hazard of the site soils is moderate. The most effective erosion control measure is the maintenance of adequate ground cover. Maintaining cover measures atop disturbed ground provides the greatest reduction to the potential generation of turbid runoff and sediment transport. During the local wet seas!Jn (October l" through March 31"), exposed soil should not remain uncovered for more than 2 days unless it is actively being worked. Ground-cover measures can include erosion control matting, plastic sheeting, straw mulch, crushed rock or recycled concrete, or mature hydroseed. Flow-control measures are also essential for collecting and controlling the site runoff. Flow paths across slopes should be kept to less than 50 feet in order to reduce the erosion and sediment transport potential of concentrated flow. Ditch/swale spacing will need to be shortened with increasing slope gradient. Ditches and swales that exceed a gradient of about 7 to IO percent, depending on their flow length, should have properly constructed check dams installed to reduce the flow velocity of the runoff and reduce the erosion potential within the June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGBl/d -KE07(){)40A4 -Projws\20070040\KEI WP Page 9 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report Geologic Hazards and Mitigations ditch. Flow paths that are required to be constructed on gradients between 10 to 15 percent should be placed in a riprap-lined swale with the riprap properly sized for the flow conditions. Flow paths constructed on slope gradients steeper than 15 percent should be placed in a pipe slope drain. AES! is available to assist the project civil engineer in developing a suitable erosion control plan with proper flow control. Some fine-grained surface soils are the result of natural weathering processes that have broken down parent materials into their mineral components. These mineral components can have an inherent electrical charge. Electrically charged mineral fines will attract oppositely charged particles and can combine (flocculate) to form larger particles that will settle out of suspension. The sediments produced during the recent glaciation of Puget Sound are, however, most commonly the suspended soils that are carried by site storm water. The fine-grained fraction of the glacially derived soil is referred to as "rock flour," which is primarily a silt-sized particle with little or no electrical charge. These particles, once suspended in water, may have settling times in periods of months, not hours. Therefore, the flow length within a temporary sediment control trap or pond has virtually no effect on the water qnality of the discharge since it is not going to settle out of suspension in the time it takes to flow from one end of the pond to the other. Reduction of turbidity from a construction site is almost entirely a function of cover measures and flow control. Temporary sediment traps and ponds are necessary to control the release rate of the runoff and to provide a catchment for sand-sized and larger soil particles, but are very ineffective at reducing the turbidity of the runoff. Silt fencing should be utilized as buffer protection and not as a flow-control measure. Silt fencing is meant to be placed parallel with topographic contours to prevent sediment-laden runoff from leaving a work area or entering a sensitive area. Silt fences should not be placed to cross contour lines without having separate flow control in front of the silt fence. A swale/berm combination should be constructed to provide flow control rather than let the runoff build up behind the silt fency and utilize the silt fence as the flow-control measure. Runoff flowing in front of a silt fence will cause additional erosion and usually will cause a failure of the silt fence. Improperly installed silt fencing has the potential to cause a much larger erosion hazard than if the silt fence was not installed at all. The use of silt fencing should be limited to protect sensitive areas~and swales should be used to provide flow control. 7. I Erosion Hazard Mitigation To mitigate the erosion hazards and potential for off-site sediment transport, we recommend the following: June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGBl/d-K£070040A4. Projecls\20070040\KElWP Page 10 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Geologic Hazards and Mitigations I. The winter performance of a site is dependent on a well-conceived plan for control of site erosion and storm water runoff. It is easier to keep the soil on the ground than to remove it from storm water. The owner and the design team should include adequate ground-cover measures, access roads, and staging areas in the project bid to give the selected contractor a workable site. The selected contractor needs to be prepared to implement and maintain the required measures to reduce the amount of exposed ground. A site maintenance plan should be in place in the event storm water turbidity measurements are greater than the Ecology standards. 2. All TESC measures for a given area to be graded or otherwise worked should be installed prior to any activity within an area other than installing the TESC features or timber harvesting. The recommended sequence of construction within a given area after timber harvesting would be to install sediment traps and/or ponds and establish perimeter flow control prior to starting mass grading. 3. During the wetter months of the year, or when large storm events are predicted during the summer months, each work area should be stabilized so that if showers occur, the work area can receive the rainfall without excessive erosion or sediment transport. The required measures for an area to be "buttoned-up" will depend on the time of year and the duration the area will be left un-worked. During the winter months, areas that are to be left un-worked for more than 2 days should be mulched or covered with plastic. During the summer months, stabilization will usually consist of seal-rolling the subgrade. Such measures will aid in the contractor's ability to get back into a work area after a storm event. The stabilization process also includes establishing temporary storm water conveyance channels through work areas to route runoff to the approved treatment facilities. 4. All disturbed areas should be revegetated as soon as possible. If it is outside of the growing season, the disturbed areas should be covered with mulch, as recommended in the erosion control plan. Straw mulch provides the most cost-effective cover measure and can be made wind-resistant with the application of a tackifier after it is placed. 5. Surface runoff and discharge should be controlled during and following development. Uncontrolled discharge may proruote erosion and sediment transport. Under no circumstances should concentrated discharges be allowed to flow over the top of steep slopes. 6. Soils that are to be reused around the site should be stored in such a manner as to reduce erosion from the stockpile. Protective measures may include, but are not limited to, covering with plastic sheeting, the use of low stockpiles in flat areas, or the June 14, 2007 ASSOC!ATED EARTH SCIENCES. INC. SGB!ld-KE070040A4 Projecrs\2007fXJ40\KE\WP Page 11 I New Transponation Center Renton, Washington Revised Subswface Exploration, Geologic Hazard, and Geotechnical Engbzeering Report Geologic Hazards and Mitigations use of straw bales/silt fences around pile perimeters. During the period between October I" and March 31", these measures are required. 7. On-site erosion control inspections and turbidity monitoring (if required) should be performed in accordance with Ecology requirements. Weekly and monthly reporting to Ecology should be performed on a regularly scheduled basis. TESC monitoring should be part of the weekly construction team meetings. Temporary and permanent erosion control and drainage measures should be adjusted and maintained, as necessary, at the time of construction. It is our opinion that with the proper implementation of the T_ESC plans and by field-adjusting appropriate mitigation elements (BMPs) during construction, as recommended by the erosion control inspector, the potential adverse impacts from erosion hazards on the project may be mitigated. June I 4, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB/Jd-KE070040A4 · Projecrs120070040lKEIWP Page 12 I New Transponation Center Renton, Washington Revised Sul1swjace Exploration, Geologic Hazard, and Geoteclznical Engineering Report Design Recommendations III. DESIGN RECOMMENDATIONS 8.0 INTRODUCTION The site contains some potential soil and foundation-oriented complications with respect to compressible soils, loose granular soils susceptible to liquefaction, and moisture-and disturbance-sensitive soils. The conclusions and recommendations in this report are based upon the assumption that the foundations, floor slab, and grading construction are observed by a geotechnical engineer or engineering geologist from our firm. The proposed project is feasible from a geotechnical engineering standpoint using pile foundations for the building superstructure, and pile-supported lower floor slabs except where the owner can assume the risk of liquefaction-induced settlements during a design level (0.34g peak ground acceleration) earthquake event. Where floor slabs will be "floated," they should be constructed as a structural slab-on-grade above a minimum of 2 feet of approved structural fill compacted to 95 percent of ASTM:D 1557. Pavement support on existing fills is possible with some near-surface remedial improvements. Remediation could consist of removing the upper foot of existing fill, recompacting the resulting subgrade, and re-using the removed existing fill as structural fill, provided adequate moisture conditioning and compaction to project specifications can be achieved. Due to the possible presence of loose surficial soils, liquefaction hazards, and/or consolidation settlement, some settlement of non-pile-supported structures and paved areas, however, is anticipated, and periodic or episodic repair may be necessary. 9.0 SITE PREPARATION Site preparation of planned building and road/parking areas that will not be supported by pile foundations should include removal· of all existing buildings, foundation elements, utilities, asphalt, landscaping, debris, and any other surficial deleterious material that are not part of the planned project. Additionally, any upper organic topsoil encountered should be removed and the remaining roots grubbed. Areas wh;;re loose surficial soils exist due to demolition or stripping/grubbing operations should be considered as fill to the depth of disturbance and treated as subsequently recommended for structural fill placement. The fill encountered in our explorations was generally in a loose to medium dense condition. However, the density, thickness, and rubble content of the fill across the site may be highly variable. We anticipate that any upper loose surficial fill soils, once recompacted or replaced June 14, 2007 ASSOCIATED EARTH SClENCES, INC. SGB!ld-KE070040A4 ProjeCIS\20070040\KE\WP Page 13 New Transportation Center Remon, Washington Revised Subsu,face Exploration, Geologic Hazard, and Geoteclmical Engineering Report Design Recommendations with structural fill, will be adequate for support of structural slabs-on-grade, pavement and other external surfacing, such as sidewalks. However, there will be a risk of long-term damage to these surfaces including, but not limited to, rutting, yielding, cracking, etc., if any uncontrolled loose fill is not completely removed and replaced with compacted structural fill. The risk can be reduced by selective removal and replacement of the most settlement-sensitive, near-surface soils. Utilities founded above loose uncontrolled fill or fill that contains abundant rubble are also at risk of settlement and associated damage. The extent of stripping necessary in areas of the site to receive structural slabs-on-grade and external surfacing, such as sidewalks and pavement, can best be determined in the field by the geotechnical engineer or engineering geologist. We recommend proof-rolling road and parking areas with a loaded tandem-axle dump truck to identify any soft spots. If construction is to proceed during wet weather, we recommend systematic probing in place of proof-rolling to identify soft areas of the exposed subgrade. These soft areas should be overexcavated and backfilled with structural fill. Some of the on-site fill and surface soils contain a high percentage of fine-grained material, which makes them moisture-sensitive and subject to disturbance when wet. The contractor must use care during site preparation and excavation operations so that the underlying soils are not softened. If disturbance occurs, the softened soils should be removed and the area brought to grade with structural fill. If the existing pavement will not be used for access and staging areas, consideration should be given to protecting access and staging areas with an appropriate section of crushed rock or asphalt treated base (ATB). The existing pavement is in such poor condition that it may be necessary to augment the pavement with A TB if it will be used for construction access and staging. If crushed rock is considered for the access and staging areas, it should be underlain by engineering stabilization fabric to reduce the potential of fine-grained materials pumping up through the rock and turning the area to mud. The fabric will also aid in supporting construction equipment, thus reducin~ the amount of crushed rock required. We recommend that at least 10 inches of rock be placed over the fabric; however, due to the variable nature of the near-surface soils and differences in wheel loads, this thickness may have to be adjusted by the contractor in the field. IO.O STRUCTURAL FILL All references to structural fill in this report refer to subgrade preparation, fill type and placement, and compaction of materials, as discussed in this section. If a percentage of June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGBl/d · K£070040A4 -Projecrs\2007004fJ\KE1WP Page 14 New Transportation Center Remon, Washingto11 Revised Subswface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Design Recommendations compaction is specified under another section of this report, the value given in that section should be used. After stripping, planned excavation, and any required overexcavation have been performed to the satisfaction of the geotechnical engineer, the upper 12 inches of exposed ground in areas to receive fill should be recompacted to 90 percent of the modified Proctor maximum density using ASTM:D 1557 as the standard. If the subgrade contains silty soils and too much moisture, adequate recompaction may be difficult or impossible to obtain and should probably not be attempted. In lieu of recompaction, the area to receive fill should be blanketed with washed rock or quarry spalls to act as a capillary break between the new fill and the wet subgrade. Where the exposed ground remains soft and further overexcavation is impractical, placement of an engineering stabilization fabric may be necessary to prevent contamination of the free-draining layer by silt migration from below. After recompaction of the exposed ground is tested and approved, or a free-draining rock course is laid, structural fill may be placed to attain desired grades. Structural fill is defined as non-organic soil, acceptable to the geotechnical engineer, placed in maximum 8-inch loose lifts, with each lift being compacted to 95 percent of the modified Proctor maximum density using ASTM:D 1557 as the standard. In the case of roadway and utility trench filling, the backfill should be placed and compacted in accordance with current local or county codes and standards. The top of the compacted fill should extend horizontally outward a minimum distance of 3 feet beyond the location of the structural slabs-on-grade or roadway edges before sloping down at an angle of 2H: IV. · The contractor should note that any proposed fill soils must be evaluated by AES! prior to their use in fills. This would require that we have a sample of the material 72 hours in advance to perform a Proctor test and determine its field compaction standard. Soils in which the amount of fine-grained material (smaller than the No. 200 sieve) is greater than approximately 5 percent (measured on the minus No. 4 sieve size) should be considered moisture-sensitive. Use of moisture-sensitive soil in st~uctural fills should be limited to favorable dry weather conditions. The on-site soils generally contained significant amounts of silt and are considered very moisture-sensitive. In addition, construction equipment traversing the site when the soils are wet can cause considerable disturbance. If fill is placed during wet weather or if proper compaction cannot be obtained, a select i/nport material consisting of a clean, free-draining gravel and/or sand should be used. Free-draining fill consists of non-organic soil with the amount of fine-grained material limited to 5 percent by weight when measured on the minus No. 4 sieve fraction with at least 25 percent retained on the No. 4 sieve. A representative from our firm should inspect the stripped subgrade and be present during placement of structural fill to observe the work and perform a representative number of in- June 14, 2007 ASSOCIATED EARTH SCIENCES. INC. SGB/ld -KE070040A4 -Projew\2007{X)4()1KE\WP Page 15 New Transponation Center Renton, Washingron Revised Subsurface Exploration, Geologic Hazard, and GeotecJmical Engineering Repon Design Recommendations place density tests. In this way, the adequacy of the earthwork may be evaluated as filling progresses and any problem areas may be corrected at that time. It is important to understand that taking random compaction tests on a part-time basis will not assure uniformity or acceptable performance of a fill. As such, we are available to aid the owner in developing a suitable monitoring and testing program. 110 FOUNDATIONS To mitigate post-construction consolidation settlement and the effects of seismically induced liquefaction, a pile foundation system is recommended. For this project, we recommend the use of 24-inch-diameter augercast piles. Driven pipe piles are a possible foundation type, but were not suggested due to the proximity of older buildings and the high levels of vibration caused by pile-driving activities. We can provide driven pile design parameters, if requested. The following sections provide augercast pile recommendations based on assumed loading conditions and soils encountered beneath the site. It should be recognized that we have assumed relatively light-loading conditions commensurate with a two-story, wood-frame structure. The IBC recommends a maximum pile length of 30 diameters unless engineering judgment allows for modifications to this limitation based on site-specific soil conditions, building type, and pile type. For a 24-inch-diameter pile, 30D equates to a maximum pile length of 60 feet. However, the pile criteria recommended for this project utilizes piles of up to 85 feet in length. In our opinion, 85-foot-long, 24-inch-diameter piles should perform adequately in compression provided the piles will not be expected to support greater column loads than 80 kips, as we have assumed. The soil conditions encountered in our explorations will provide adequate confinement of the piles (even during a period of partial soil column liquefaction) so that "slenderness" is not considered a significant design issue. 11.1 Augercast Piles We recommend that the construction. of piles be accomplished by a contractor experienced in their installation. Fill soils can have concrete, brick, wood, and other demolition waste in them, and soils of alluvial origin may have gravel lenses or large cobbles present in them. It may be necessary to have a backhoe present during pile installation to dig out obstacles and backfill the excavation prior to drilling piling. If obstacles are encountered at depths where removal with a backhoe is not feasible, it might be necessary to modify the pile layout to replace piles that cannot be completed according to the original design. Observation of pile installation by AESI is important to verify that the subsurface conditions observed at pile locations are consistent with the observations in our subsurface explorations, and consistent with assumptions made during preparation of the recommendations in this report. The City of Renton will likely require such inspections of foundation piles. June 14, 2007 ASSOCIATED EARW SCIENCES, INC. SGB!ld -KE070040A4 -Projem\20070040\KEIWP Page 16 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Design Recommendations The augercast piles will gain support from end bearing and skin friction. Augercast piles are formed by drilling to the required depth with a continuous flight, hollow-stem auger. Fluid grout is then pumped down the hollow stem under pressure as the auger is withdrawn. Appropriately designed reinforcing steel cages are then lowered into the unset grout A single reinforcing bar is installed for the full length of the pile for transfer of uplift loads. Since the grout is placed under pressure, actual grout volumes used are typically 15 to 50 percent greater than the theoretical volume of the pile. Actual grout volumes for piles constructed through some types of fill and peat can be much more. The pile contractor should be required to provide a pressure gauge and a calibrated pump stroke counter so that the actual grout volume for each pile can be determined. Typically, a nine-sack, minimum 4,000 pounds per square inch (psi) grout mix is used for augercast piles. Once complete, the piles would then connect to a pile cap and grade beam support system for the building foundation. Typical allowable capacities for the augercast piles are given in Table 1. Development of the design capacities presented in Table I requires a minimum overall pile length of at least 20 pile diameters. To satisfy required length-to-diameter ratios, 24-inch piles are limited to 85 feet in length. Allowable design axial compressive loads may be increased by one-third for short-term wind or seismic loading. Anticipated settlement of the pile-supported foundations will generally be on the order of V2 inch. Table 1 Augercast Pile Recommendations Estimated Vertical Maximum Compressive Lateral Depth of Pile Diameter Length Capacity Capacity fixity Uplift Capacity (inches) (feet)''> (tons) (tons)a> (feet)"> (tons)''l 24 85 40 JO 22 20 < 1 > P!le length based on EB-4, EB-5, and EB-6 for beanng layer occurnng between 75 and 85 feet depth. Beanng layer encountered at 35 feet in EB-3, but was not used for design. (l) Allowable lateral capacities are for fixed-headed conditions (incorporation into pile caps and grade beam system), and 1/i inch of deflection at the ground surface. Greater lateral capacities are possible for greater allowable deflections. -... <3J The depth of fixity does not include the code-required 20 percent increase for reinforcing cage design. ''' Uplift capacity is based on minimum pile length of 75 feet Piles with lateral spacing less than 6 pile diameters from another pile along the direction of force should be considered to be in the zone of influence and the lateral capacity and the reduction factors presented below should he used. If the lateral contribution of the piles is June I 4, 2007 SGBl/d -K£070040A4 • Projeas\10070040lKE\WP ASSOCIATED EARTH SCIENCES, INC Page 17 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Report Design Recommendations more critical to the practical design of the structure, we can provide a comprehensive lateral pile analysis. Such an analysis would present lateral pile capacities taking into account the interaction between piles. Based on the loose conditions of the soils through which the augercast piles are to be excavated, care should be taken in construction planning to allow grout time to set prior to drilling adjacent piles. Typically, 24 hours of set time is recommended for piles closer than 3 diameters or 10 feet, whichever is greater. The 24 hours can be reduced for adjacent piles drilled on different workdays. 11.2 Group Effects Where piles are installed in groups and subject to lateral loading, reductions in lateral capacity to account for group effects should be included in design. The effects of group performance should be considered where piles are spaced closer than 6 pile diameters center-to-center and are aligned in the direction of loading. Piles should not be spaced closer than 3 pile diameters center-to-center to achieve full vertical and uplift capacity. If piles are staggered in the x and y directions a minimum of 3 pile diameters, there is no reduction in lateral loading. For the determination of individual capacities for load application parallel to the line of spacing, the following spacing and reduction factors presented in Table 2 should apply. The last pile in a row can be assumed to develop the full lateral capacity. Table 2 Lateral Reduction Factors Pile Spacinl! Reduction Factor 6 diameters 1.0 -5 diameters 0.8 4 diameters 0.6 3 diameters 0.4 11.3 Passive Resistance and Friction Factors Lateral loads can be resisted by friction between the pile caps and grade beams and the existing fill soils or structural fill, or by passive earth pressure acting on the buried portions of these elements. The foundations must be backfilled with structural fill and compacted to at least 95 percent of the maximum dry density to achieve the passive resistance provided below. We recommend the following design parameters; Jum, 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB!ld -KE070040A4 -Projws\10070040IKE\WP Page 18 New Transportation Center Renton, Washington Revised Subsurface Exploration, Geologic Hazard, and Geotechnical Engineering Repon Design Recommendations • Passive equivalent fluid = 200 pounds per cubic foot (pcf) • Coefficient of friction = 0.30 The above values are allowable and include a safety factor of at least 1.5. 12.0 FLOOR SUPPORT As discussed earlier in this report, existing site soils are considered to be settlement-prone, and we therefore recommend that floor slabs be designed as "floating" slabs-on-grade or be structurally supported on pile foundations. Where potentially large-scale liquefaction-induced settlement can be tolerated, site soils can be used to support slab-on-grade floors, sidewalks, or other similar structures contingent upon adequate remedial preparation and understanding of uncertainties in settlement performance. Repairs to damaged "floating" slabs-on-grade should be expected following significant seismic shaking. Slabs or pavement to be supported on grade should be supported on a 2-foot-thick structural fill mat. All fill beneath slabs or pavement must be compacted to at least 95 percent of ASTM:D 1557. The floor slabs should be cast atop a minimum of 4 inches of clean washed crushed rock or pea gravel to act as a capillary break. Areas of subgrade that are disturbed (loosened) during construction should be compacted to a non-yielding condition prior to placement of capillary break material. It should also be protected from dampness by an impervious moisture barrier at least 10 mils thick. The impervious barrier should be placed between the capillary break material and the concrete slab. m"·-yy··.,··y·y~c-y--y---y-y·y··yy-y--- fi3.0 DRAINAGE CONSIDERATIONS ~y-y-v-/·,-~. !-' ' ''~ r All exterior grade beams should be provided with a drain at least 12 inches below the base of , the adjacent interior slab elevation. Drains should consist of rigid, perforated, polyvinyl ! chloride (PVC) pipe surrounded by washed pea gravel. The drains should be constructed with sufficient gradient to allow gravity discharge away from the building. Roof and surface runoff should not discharge into the footing drain system, but should be handled by a separate, rigid, tightline drain. In planning, exterior grades adjacent to walls should be sloped downward ~awav from the s.tructure to achieve surface drainage. ,. f-;.j·._;..> -~ ..>->-.... -A .. A., . ,.>-..> -.•• _>, . ~ . ' ' j~ -~J...-"-''_/-· 14.0 PAVEMENT RECOMMEND A TIO NS The majority of the parking and access areas are planned for those portions of the site underlain by fill materials overlying loose/soft soils. Considering the poor condition of the June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGB!fd-KE070040A4 -Projew\10070040\KE\WP Page 19 New Transportazion Cemer Renton, Washington existing pavement and constant bus traffic, support of pavement. Revised Suhswface Exploration, Geologic Hazard, and Geotec!mical Engineering Repon Design Recommendations some remedial measures may be necessary for Ideally, pavement sub grades would be prepared by selectively removing, replacing, and recompacting the upper I to 2 feet of site soils to provide a uniform thickness of compacted structural fill to support bus drive and parking lot pavement sections. The upper existing soils are, however, moisture-sensitive and contain scattered organics and rubble. In addition, site work may occur during the wetter winter months or during wet site conditions. Therefore, it is recommended to assume that some of the site soils may not be reused as structural fill and may need to be replaced with imported select soils. During the winter months, a 50-percent replacement assumption is reasonable, while during the drier summer months, a 25-percent replacement assumption is reasonable. The use of unit prices for removal and replacement of unsuitable soils is recommended. Alternatively, to reduce the depth of unsuitable soil removal, an engineering stabilization fabric or geogrid reinforcement could be placed over the stripped subgrade prior to filling. The addition of an engineering stabilization fabric or geogrid permits heavier traffic over soft subgrade and increases the service life of the system. The fabric acts as a separation barrier between relatively fine-grained surficial materials on the site and the load-distributing aggregate (sand or crushed rock). A separator reduces the loss of costly aggregate material into the subgrade and prevents the upward pumping of contaminating silt into the aggregate. The use of fabric or geogrid would be a field decision based on actual conditions encountered. A unit price for separation fabric is recommended. Upon construction of the 2-foot structural fill (reworked site soils or imported fill), a pavement section consisting of 4 inches of asphalt concrete pavement (ACP) underlain by 2 inches of 5/,-inch crushed surfacing top course and 6 inches of 1 \Ii-inch crushed surfacing base course is recommended for heavy (bus) traffic areas. For light-duty car parking areas, a pavement section consisting of 3 inches of ACP over 4 inches of crushed rock surfacing over a properly prepared subgrade can be used. The crushed rock courses must be compacted to 95 percent of maximum density. Given the potentially variable in-place density of the existing fill sub grade, some settlement of paved areas should be anticipated unless the existing fill is entirely removed and replaced with structural fill. 15.0 PROJECT DESIGN AND CONSTRUCTION MONITORING At the time of this report, site grading, structural plans, and construction methods have not been completely finalized. We are available to provide additional geotechnical consultation as the project design develops and possibly changes from that upon which this report is based. June 14, 2007 ASSOCIATED EARTH SCIENCES, INC. SGBl/d -KE070040A4 Projectsl2007004(}1KE1WP Page 20 New Transportation Center Renton, Washington Revised Subsu,jace Exploration, Geologic Ha.wrd, and Geoteclmical Engineering Repon Design Recommendations We recommend that AESI perform a geotechnical review of the plans prior to final design completion. In this way, our earthwork and foundation recommendations may be properly interpreted and implemented in the design. We are also available to provide geotechnical engineering and monitoring services during construction. The integrity of the pile foundation system depends on proper site preparation and construction procedures. In addition, engineering decisions may have to be made in the field in the event that variations in subsurface conditions become apparem. Construction monitoring services are not part of this current scope of work. If these services are desired, please let us know, and we will prepare a cost proposal. We have enjoyed working with you on this study and are confident that these recommendations will aid in the successful completion of your project. If you should have any questions or require further assistance, please do not hesitate to call. Sincerely, ASSOCIATED EARTH SCIENCES, INC. Kirkland, Washington ~__$~ Susan G. Beckham, P.E. Senior Project Engineer Attachments: Figure 1: Figure 2: Figures 3 & 4: Appendix: June 14, 2007 SGB!id-K£070040A4-P,ojew\20070040\KE\WP Vicinity Map Site and Exploration Plan Liquefaction Analysis Exploration Logs Laboratory Testing Results Kure D. Merriman, P.E. Principal Engineer ASSOCIATED EARTH SCIENCES, INC. Page 21 ii I 0 I • i; u ~ [, j i 0 ~ ~~~~~,~~~*t~M~~~R~~~~1~~/~~t~~1~~~~~.~~wr@~~,,ir~1rr 1 ~~;:~~~1~~w~1it1JiNt~~!~1twJ~w.r~ 1 ~~~~~¥.tW~~~~~,.&~~~@~~~~~:t)x:~:~.;}:~~r~:~~ 1 ::;;i L::r-. -t' I •• -------------I .:., -~ _.., ~· '* 1.,/'' -...... ~ ('~ ) ( '•\· I,,;;'. --i',!c lt--,----·-------~ .,-: , , '\ilrll''? -,.,, .~!.,~ _-' -1'·b -·~· ,.. ~•, ... ] -: V'• --··--i-, \. __ _::_~,,: l.Lf[·~(; 1''.:-·--,-.... ,\. t\\ :.,•As•"'-' t [I .. ! -11 I ::[; -S:.. ; • .-, •,,, [p1 \' ', ~'.'.'.-f;J_~· :·· , ·, ":r: .. : ,r::;,;/L l .:;~, :..:: 1' .::.!; .,_ I (" ... --:,1, I ~ ,'1 .. IC: , -..., rfl-~ ' ,· .,.,,, .. '. \"· ,_ I I I i I ,C: I . '". 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' :.-:, Y'-iii!;; l " --. , . r I ·"· I ' -I 3' / ., .. 11, / ,_ --,· .. · · I · · t'J •~,I ' • Rr ,.-. r •, :_,-,,:·'-, i<t'JA r-R P-IL. ·--, ,~------i i' 1·.:; 1 -~ ·:J 'l°l'.·.1(, .. , (-..z.· , .. I . rf-.' ")1;; . -0 RT "I.T\t-, --,,, --1 ' I ...,.. '" l ,_, ·~ 17-.,-, I '.'.'.''"" ~ .0--;: W Jy..,ri;'; ·-. 'l. 1' -· :--::. 1 .. :) I ;:.' I .... .~~;.· 1 ·r,:J;{ ""' " -'.. '" s<-c I ' /' '-"--' -.. , .> I ',-___, l 1_ I, ~J,.~ • I "' ·c~,,,,;;.,. •'-"r ' r----r-~· ---, ,---~8:J-=~r 1}i~r,~1ui '-/', ·~-~~ ~ ,.! l ·~ I !, , , I ·,/~ r··~ ~.1,. ssi,,· 1-----1._· .. ,vi,)_....:·. 11 1 'wY. ,\ , 1 "~';:/----~L-___ ' f·· I c-·1 r ,; . ,:. _. .~.. " i • , ~,~i----·-----c;..., ----;, i'>i r . -..: ,.1 -I , / l i ·~:;"'' ; ~~p.;J ~~'l::' ~· -- '..... lt"! .._J I~ N A NO SCALE Associated Earth Sciences, Inc. ~ L±J ~~ ~~ VICINITY MAP NEW TRANSPORTATION CENTER RENTON, WASHINGTON .%.:1 .~-:'/ ;:: I ;;.- I I _::<,I ~;~· I ... ;. '\!';:.-:. ... I .·.:: ''-,, If{·· l,t?f.///F .' ,' I i.':tc_ -i:~11 ~-i ·;:~ I ~~.:: -· -·-~--.. . . ·~/:"/ :'l!LFVET ,..,-1(--r---,1 · I '::·2 ~ ilt-; i ,I '' "'' (:r. '.:•l,ff'< '·1 l ... ,J; ,.©2004 Thomas Bros. Maps',:'.\\ r~~1fi~iJf$:~[{~iliflj!f1[fjT~f([~~~-{{t1ff;i~lii;) (.t.<•!:. ,' t./': .r' FIGURE 1 DATE 3/07 PROJ. NO. KE070040A 0------------------------------------------------------------------- i /, '' ! I: i I\ ' ' 1 , , , ' ' ' , I J ' I :! ,, 'I i )l 1, I \ I EB-6 (85') ' ' -,. i ) ,, '' ! T I I ; \ I \ ... ~ ---. ~~~r,.:;:'--ip,i•--~· , i I u ' .----} Il ' I PR POOE~ UILDIN I + ', 1--!=-4 ,( I /' 5') y 1IT1 • ___ , ' ' --, ' __ , ~ --- I ' I , , ...... , ' ' , -I _,--I I 1\ I '-f , , -1 EB-$ ; (75/) ~ : ~ , , , I ' ..... ,-~ ' ' c\ ~ _....,_ N. 4TH STREET ,' I I ' , , ' I I ' I , ' l I I ' • ' ! ' , , ' ' ' • I I I ' \, \ -' I ' I ' ' ' ' ' -, I I ' :i ' I ' I t, ' , ,, ' ' I l I ' -~' I ' f I • /I ' ' ' , ' , , ' ' l t =~R;ef;e~re~n;c;e:~PA=C~E=================================~::::::=:;;;:;== ! Associated Earth Sciences, Inc. SITE AND EXPLORATION PLAN FiGUREZ DATE 3/07 l m liiii! flliipij i.i ~ NEWTRANSPORTAION CENTER i !!S'S ~ ~ l:w (..di RENTON, WASHINGTON PROJECT NO. KE070040A "--===-=::......:==-==-=-=-----------------__;,:_:.:;_..;--- s fi f 0 ~ • m " • I £ > u • ... l LIQUEFACTION ANALYSIS New Renton Transportation Center Hole No.=EB-3 Water Depth=7 ft Shear Stress Ratio Filctor of Safety Settlement (fl) O 2 0 1 5 0 (h) 50 0 1T"C::TTTTT":I:::I=! I I I I I I 10 20 30 40 50 60 70 / ,, fs=1 CRR-CSR - Shaded Zone has Liquefaction Potential I JI l I I I I l I ' I II I I ' I I I I I I Wei-Dry- S=10.10in. Magnitude=7 Acceleration=0.34g Sail Description Raw Unit Fines SPT Weight % --,====---------, 30 130 5 Silty Sand Fill Silt (Alluvium) Silty Sand 5 90 60 4 95 45 "m Well graded Sand ~P. 15 110 4 !~~~ Fine lo medium Sand 9 105 5 Silty Sand 4 95 49 Sill 3 85 70 Sitt and peat 9 100 82 Silty Sand {Pre-Vashon) 44 135 20 39 132 21 35 131 12 CivilTech Corporation KE070040A Figure 3 i LIQUEFACTION ANALYSIS New Renton Transportation Center Hole No.=EB-5 & EB-4* Water Depth=7 ft Shear Stress Ratio Facr.or of Safety Settlement Soll Description Magnitude=7 Acceleration=0.34g (n) O 2 01 5 O(in.J 50 Q ,--.--r:::-.--.--r:-r=:r::=r::=:c::i I J I I I I I I I ! I It I I J Raw Unit Fines SPTWeight % ~~~~~---------30 130 5 Silty Sand Fill 15 1, 30 45 60 75 \ , ·' 90 Is CRR ~ CSR~ Shaded Zone has Uquefactfon Potential 105 CivilTech Corporation I I I I I I I ' I 1 l ( I J I I I I I I I fj\ tt{ I I I I ~ Wet-D,y- S=2867in. KE070040A 8 98 60 SIil (Alluvium) 8 98 45 Silty Sand nr Sand Silty Sand Sand Silly Sand Sill Sand Silty Sand Slit 2 90 4 2 90 4 3 85 70 D 80 70 3 65 70 5 67 60 26 120 26 11 100 50 10 105 30 27 121 5 14 105 40 10 110 12 34 130 4 31 125 50 12 105 30 ;f 66 135 5 7t 34 120 55->f Figure 4 APPENDIX C • 0 • 0 , D Well-graded gravel and u OCl ro -Oooo'GW gravel wi1h sand, little to u: • <? o'?o • no fines • C 0 ~ • u: • ;; '#. 00 0 Poorly.graded gravel > "o" > 0 • moo 000 • Ui:7.i \11 <l 0 GP and gravel with sand, ai o• o,o 'o .. 000 0 ,o 0 ,o little to no fines 0 ci 00 o,o N ,ez 00 0 ,o 0 ci oc • 0 • 0 z "' 0 Silty gravel and silty C c.,,- 0 ro • -GM gravel with sand £.S • • 0 • 0 .,, • J!! • • C C -· u: ·a :ll rr * -. . ~ Clayey gravel and rr !!! ,., GC clayey gravel with sand • -:~ > 0 ~ "' (!) C Well-graded sand and • C fi 0 " sand \Mth gravel, little ~ TI SW ~ fil :::: to no fines ::; u. C •••• ii:.·.· ... -" * Poorly-graded sand ·;; m UJ "' . SP and sand with gravel, .,, little to no fines • C ·~ (!) Silty sand and d, ~ SM silty sand with • 0 gravel u . Clayey sand and ~ SC .,, clayey sand with gravel C • UJ Silt, sandy silt, gravelly silt, • ML silt with sand or gravel > -~ C UJ •• 0 >-fi 0 -"' m Clay of low to medium N Um ci -g j CL plasticity; silty, sandy, or z (I):-=: gravelly clay, lean clay m • E • ;:::J • • UJ.,, Organic clay or silt of low • ·s a. .a-E ~ OL plasticity 0 ::; _o Elastic silt, clayey silt, silt "" MH with micaceous or 0 "' diatomaceous fine sand or ' silt ~ 0 Clay of high plasticity, UJ .,, CH sandy or gravelly clay, fat • C clay with sand or gravel ·a; " d, Organic clay or silt of C ii: medium to high plasticity z..~ U) Peat, muck and other ..c to= PT highly organic soils El e, & :,: 0 Terms Describing Relative Density and Consistency Density SPTl21 blows/foot Coarse-Very Loose Oto 4 Grained Soils Loose 4 to 10 Medium Dense 101030 Test Symbols Dense 30 to 50 Very Dense >50 G = Grain Size M "" Moisture Content Consistency SPTl21 blows/foot A = At1erberg Limits Very Soft Oto 2 C = Chemical Fine-Soft 2to 4 DD = Dry Density Grained Soils Medium Stiff 4 to 8 K = Permeability Stiff B to 15 Very Stiff 151030 Hard >30 Descriptive Term Boulders Component Definitions Size Range and Sieve Number Larger lhan 12" Cobbles 3~lo 12" Gravel Coarse Gravel Fine Gravel 3~ lo No. 4 (4.75 mm} 3" 10 3/4" 3/4' to No. 4 (475 mm) Sand Coarse Sand Medium Sand Fine Sand No 4 (4.75 mm) to No. 200 (0.075 mm) No 4(4.75mm)loNo.10(2.00mm) No 1 O (2 00 mm) to No 40 (O 425 mm) No. 40 (0.425 mm} to No. 200 (0.075 mm) Silt and C!ay Smaller than No. 200 {0.075 mm} (3) Estimated Percentage Component Percentage by Weight Trace Few Little With <5 5 to 10 15to25 -Non-primary coarse constituents: 2:_ 15% -Fines content bet:ween 5% and 15% Moisture Content Dry -Absence of moisture, dusty, dry to the touch S1igh11y Moist -Perceptible mois1ure Moist -Damp but no visible water Very Moist -Water visible but not free draining Wet -Visible free waler, usually frorn below water table Symbols Sampler Type Blows/6" or portion of 6" I • " • Sampler Type Description 3 O'' 00 Split-Spoon Sampler (•] Cement grout surface seal Ben!onite seal 2.0"0D Split-Spoon Sampler (SPT) 3 .2s~ OD Splil·Spoon Ring Sampler . . Filler pack wilh :·:· blank casing :-· section Bulk sample Grab Sample 3 O" OD Thin-Wall Tube Sampler (including Shelby tube) :: Screened casng . ·· or Hydrotip -.-with filter peel< o Portion not recovered (l) Percentage by dry weight f2l {SPT) Standard Penetration Test (ASTM D-1586) <3) In General Accordance Vvilh Standard Practice for Descriplion and Identification of Soils (ASTM 0·2488) _ .· End cap 1~> Depth of ground water .'! ATD == At time of drilling ~ Static water /eve! (date) <5J Combined uses symbols used for fines between 5% and 15% ~ 5' Classifications of soils in this report are based on visual field and/or laboratory observations, which include density/conslslency, moisture condition, grain size, and -;.:. plasticity estimates and should not be construed to imply field or laboratory testing unless presented herein. Visual-manual and/or laboratory dass!fica\ion 5 methods of ASlM D-2487 and D-2488 were used as an identification guide for the Unified Soh Classmca!lan System. ;======================================= f Associated Earth Sciences, Inc. EXPLORATION LOG KEY FIGURE A1 Associated Earth Sciences, Inc. Exploration Loq ~ CE ~ ~ ffl Project Number I Exploration Number I Sheet ' KE070040A EB-1 1 of 1 > ' ' Project Name New T[gns12ortatiQD Geater Ground Surface Elevation (ft) Location Benton We, Datum t..r/A Driller/Equipment Sortecb Track Big Date StarVFinish 2l21t01 2l2jlQ] Hammer Weight/Drop 140# I 3n" Hole Diameter (in) 4 iacbes g C ~: "' • u-0 • • ·-0 ~i • lg ~ .0 Blows/Foot • '5. C. ~[ _, . >-s E ,: ~ -. ~ • T m "'"' .!: .Q 0 "' 0 '?-"' ~ DESCRIPTION u 15 10 20 30 40 Fill 2 inches asphalt, 2 inches base rock. loose to medium dense, moist, black, silty fine to medium SAND, with gravel -5 S-1 Quaternary Alluvium 4 .. Medium stiff, moist, dark gray, dayey SILT, with organics 4 -5 Very soft, very moist, dark gray, sandy SILT. with very thin fine sand S-2 1 .. , seams. 1 1 ,y: -10 Very soft, saturated, dark gray, sandy SILT, with peat stringers and wood. S-3 /1 ' l"-11,2· ·----------- Bollom of exploration boring al 11 5 feel Ground waler al 9 feet -15 - -20 f-25 -30 ~ -35 Sampler Type (ST); [Il 2" OD Split Spoon Sampler (SPT) 0 No Recovery M .. Moisture Logged by: SGB II] 3" OD Split Spoon Sampler (D & M) I] Ring Sample ';/. Water Level {) Approved by: [QI Grab Sample fZ.] Shelby Tube Sample?: Water Level at time ofdrming (ATO) Associated Earth Sciences, Inc. Exnloration Loq lm []3 ~ ~ m Project Number I Exploration Number I Sheet ' KE070040A EB-2 1 of 1 Project Name New Traniu2ortatioo Ce[)ter Ground Surface Elevation (ft) Location Renton WA Datum •''A Driller/Equipment Bortecb Irac~ B.ig Dale start/Finish 212HO:Z 2l2HOZ Hammer Weight/Drop 140* I 3n" Hole Diameter (in) A.me"-- g C -,;; "' -u-.Q >' -• -o "m ~" ~i _, -. Blows/Foot /!!. ~ 0. ~t '5. s E -. • • "u, tE 1'! 0 ~ 0 T "' 8 ~ffi is DESCRIPTION 10 20 30 40 Fill 2 inches asphalt concrete, 2 inches base rock. Loose lo medium dense, moist, dark brown, silty fine lo medium SAND, with gravel and asphalt. S-1 Quaternary Alluvium 6 ... , 2 Medium stiff, moist, brown and gray mottled, SILT, with fine sand, few ' organics 5 ~ S-2 2 ... , -.Y~lY. moh;J, redwbrown.Ji..n.~._mw s_fil~--·-- 5 J Bottom of explora1ion boring al 6 5 feet No ground wa1er 10 ~ 15 1--20 -25 -30 ~ -35 ~ Sampler Type (ST}. [D 2" OD Split Spoon Sampler (SPT) 0 No Recovery M • Moisture logged by: SGB 0 [D 3~ OD Split Spoon Sampler {D & M) I] Ring Sample 'ii' Water Level 0 Approved by: IQ! Grab Sample \ZI Shelby Tube Sample Y. Water level at time of drilling (ATD) < --Associated Earth Sciences, Inc. Exploration Loa ~ [3J ~ lwJ ~ Project Number I Exploration Number I Sheet ' KE070040A EB-3 1 of 2 ' ' ' Project Name New T rans~ortation Center Ground Surface Elevation (ft) Location B!mtQn WI!, Datum tJlA Driller/Equipment E!ort§cb Trac~ Rig Date Start/Finish 2l2:1 lDl 2l21 lOZ Hammer Weight/Drop 140#/30" Hole Diameter {in) 4 iocbes @. 5 ~: • • o-t; -o =1i5 • '2 .,, ~.o Blows/Foci\ • ,5 ~ ~E -' . I-~o. l; ~ ~ s E ~~ ,: E • • T m Cl<J> ~in D <IJ 0 ,5 DESCRIPTION (,) 10 20 40 0 30 Gravel surfacing/no heave observed or reported fill Medium dense, moist, black, silty fine lo medium SANO, with gravel and asphalt (SM). ' S-1 Quaternary Alluvium 2 .... , Very moist. brown mottled, sandy SILT, with fine sand seams to 1 inch ' I-5 thick (ML). S-2 Very moist, brown mottled, silty very fine SAND, stratified, with lenses of ' ..... silt and clean sand (SM). , ' -10 Very moist, brown, clean fine 10 coarse SAND. with gravel, trace silt, 50% S-3 5 .... ,. recoveiy (SW) "' 7 ' -15 Water added after 15-foot sample. S-4 Saturated, fine to medium SAND, with lenses of fine gravel to 6 inches 5 ' Q thick, trace silt {SP). 5 4 -20 -Saturated, gray, siltYSANO 10 SILT, Wilh fine sand and peat and lenses of S-5 ' .... , fine sand to 1 mch thick (SM/Ml) 2 2 -25 Wet, gray, SILT, with peat stringers and fine sand (ML) S-6 3 .... , 2 , -30 Wet, gray, SILT, and brown PEAT (MUPT}. S-7 3 '9 4 ~ ' -35 S-8 Gravels reported by drHler at 35 feet. 17 Saturated, brown, silty fine lo coarse SAND, with gravel, trace organics, 23 ...... 50% recovery (SM) 21 Sampler Type (ST}. I] 2" OD Split Spoon Sampler (SPT) 0 No Recovery M -Moisture Logged by: SGB I] 3" OD Spli1 Spoon Sampler (D & M) (] Ring Sample 5:/. Water Level() Approved by: IQ! Grab Sample [Zl Shelby Tube Sample ~ Water Level at time of drilling {ATD) Associated Earth Sciences, Inc. Exoloration Loa ~ w ~ ~ m Projecl Number I Exploration Number I Sheet . KE070040A EB-3 2 of 2 . . Project Name New Transport2tioo Q~Otfl( Ground Surface Elevation (ft) Location RenJQn WA Datum "" Driller/Equipment Bortegh Trac~ Big Dale Start/Finish 2l2j lOZ 2i2 j lOZ Hammer WeighVDrop 140# 130" HoJe Diameter (in) 4incbes @: " o-~ ~= 1!) .,, -0 ID ,e " ~.,, ~.9! _, " Blows/Foot ID £ ~ ~[ I- ~ s E $~ ~ ~ ~ ID T m (!)"' J!:! ..Q 0 "' 8 .g"' ~ DESCRIPTION 10 20 30 40 5 S-9 Saturated, brown. fine to medium si!ly SAND, with gravel, 50% recovery (SM). 13 19 '39 20 -45 Same as above. S-10 10 14 .. ,, ----21 Bollom of exploration boring at 46.5 feet Ground water al 1 l feel ATD -50 -55 -60 -65 -70 ~ -75 Sampler Type (ST) [[] 2" OD Split Spoon Sampler (SPT) 0 No Recovery M -Moisture logged by: SGB [[] 3" OD Split Spoon Sampler (0 & M) I] Ring Sample 5l. Waler Level O Approved by: ~ Grab Sample IZl Shelby Tube Sample.!. Water Level al time of drilling (ATD} Associated Earth Sciences, Inc. Exoloration Lon ~ G] ~ ~ m Project Number I Exploration Number Sheet . KE070040A EB-4 1 of 3 Project Name New Traos~ortation Center Ground Surface Elevation (ft) Location Beo!oa WA Datum ..bl'" Driller/Equipment Ca,gade/CME 85 Date Startlfinish 2l27.lOI 2f2llDI Hammer WeighVDrop HO#l~Q" Hole Diameter {in) -B iacbes g C ~~ .,, 3 20 =~ • ~ .D • ie Blows/Foot • ~ C. ~e ~ 0 >- C. s E ~~ •;; ~ . • S: E • 0 • T • ""' ~ffi ,5 0 <n 0 DESCRIPTION l) 10 20 30 40 0 -P.sphalt _____ Fill ~ ·------- Crushed rock and pit run, sand and gravel. ----------------------------Quaternary Alluvium ----- " 5 Moist, li~ht olive-gray, weakly stratified, sandy SILT and silly fine SAND S-1 ' ... (MUSM 2 ' ~ 10 Moist to wet, light olive-gray, stratified, silty fine SAND and fine lo medium S-2 ' .. ~ SANO, trace silt, trace thin laminae of organics (SM/SP) :i: 4 ' -15 Same as above 3 S-3 3 ... , 3 20 Wet, light gray, non-stratified, fine to coarse SANO, trace to few silt S-4 8 ... ,. (SW/SM) 12 16 -25 Wet, tight gray and light brown, interbedded PEAT and fine to coarse S-5 5 .. 7 SAND, lrace sill. trace organics (PT/SW). 7 ,0 -30 Wet. light olive-gray, strallfied, clayey SILT (ML) S-6 D ... , 1 . ' -35 Wet, light olive-gray and light brown, interbedded silty CLAY, PEAT, and S-7 2 ~,, fine to coarse SAND, trace silt, and organics (CUPT/SW) 4 7 . fi ' " ~ Sampler Type (ST). I [Il 2" OD Split Spoon Sampler (SPTJ D No Recovery M-Moisture Logged by: JDC • ID 3" OD Split Spoon Sampler (D & M) (J Ring Sample 5J_ Water Level O Approved by: 0 IQ] Grab Sample \21 Shelby Tube Sample:?. Waler Level at time of drilling (ATD) Associated Earth Sciences, Inc. Exoloration Loa !ffl GI] ~ ~ m Project Number I Exploration Number I Sheet ' . KE070040A EB-4 2 of 3 ' . ' Project Name New Tran§goltlb<m Qenter Ground Surface Elevation (ft} Location Benton W~ Datum ... 1111 Driller/Equipment Qas~,;de/CME 85 Date StartlFinish 2l2Il01 2l2Zl0Z Hammer Weight/Drop 140# / 30" Hole Diameter {in) -BiocbSs g C ]~ J!! " u-0 • • ·-0 =~ • <e Blows/Foot ~ ~ 0. ~~ -' . ~[ •-" . 1i s E ;;:~ .& ..e ~ 0 rn 0 U) Cl T U) 8 §1 a, £ DESCRIPTION 10 20 30 40 0 S-8 Wet, light o1lve-gray, non-stratified, silly fine SAND {SM). 7 i..,, 12 9 '-45 Same as above S-9 0 5 10 ' -50 Wei, light olive-gray and light brown, interbedded PEAT and silly CLAY S-10 1 (PT/CL) 5 10 5 L 55 Wet, ligh1 olive,gray, inlerbedded, clayey SILT and silty fine SAND S-1 t a .. , (MUSM) 10 15 ' 60 Wet, light olive-gray, sandy SILT (ML) S-12 7 i..,, 10 11 L 65 B!ow count not SPT: 300 pound -down hole hammer and 2-inch spoon. S-13 3 .. 5. i..,, Wet, light olive-gray and light brown, stratified, clayey SILT, few peal in 1~ 5 to 2-inch stringers (MUPT /ML) 6 •Equivalent SPT L 70 Blow count not SPT. 300 pound -down hole hammer and 2-inch spoon. S-14 7 ... " Wet, lighl olive-gray, weakly stratified, s,Uly fine SAND (SM)_ • ' , . 10 -75 Wet, light olive-gray, weakly stratified, silty fine to medium SANO, trace S-15 11 ... 7 scaltered peaty organics (SM). -1B 19 Sampler Type (Sl): rn 2" OD Split Spoon Sampler (SPT) 0 No Recovery M-Moisture Logged by: JDC rn 3" OD Split Spoon Sampler (D & M) I] Ring Sample Sl. Water Level O Approved by: ~ Grab Sample [Z] Shelby Tube samp~-?-Water Level at time of drilling {ATD) Associated Earth Sciences, Inc. Exoloration Loa I~ CE ~ ~ IBiil Project Number I Exploration Number I Sheet . KE070040A EB-4 3 of 3 Project Name New IrnaspQ[:tatiQIJ Center Ground Surface Elevation (ft) Location Ren!oa WA Datum ~''"' Driller/Equipment Qs1scade/CME 85 Date Start/Finish 2l2ZlOZ 2f2Zl07- Hammer WeighUOrop 1 ,in.u, / ".lQII Hole Diameter (in) ~bes g C ~. " " .20 =~ ~~ " .., ~ .c Blows/Foot • £ "-~[ ·-" . f- ~ s E 5' ~ .s .Q " • • "'U) • 0 T U) 0 ~ ro £ DESCRIPTION () 0 10 20 30 40 Same as above. 13 S-16 14 .. ,, 19 -85 Wet, light olive-gray, weakly stratified, silty fine to medium SAND (SM) S-17 1 .. ,, 2 10 -90 Wet lo moist, light olive-gray, stratified, fine to medium SAND, few sill, S-18 10 trace organics in thin laminae (SM). 33 66 33 95 Wet, light olive-gray, stratified, sandy Sil T {ML) S·19 15 17 .. ,. -· ----·---17 I Bollom or explor.ition boring at 96 5 feet Ground waler at 10 fee1 .... 100 ,-,05 -110 - -115 Sampler Type {ST): [D 2" OD Splil Spoon Sampler (SPT) 0 No Recovery M • Moislure Logged by: JDC [D 3" OD Spli1 Spoon Sampler (D & M) I] Ring Sample l.1 Water Level() Approved by: ~ Grab Sample [ZI Shelby Tube Sample-l-Waler Level at time of drilling {ATD) ~ 0 • • w • Associated Earth Sciences, Inc. Exploration LoQ l~J [J3 ~ ~ ~ Project Number I Exploration Number I Sheet . . KE070040A EB-5 1 of 3 Project Name New Trans12or@tiQD Ceoter Ground Surface Efevatlon (ft) Location Renton WA Datum .bl" Driller/Equipment Bortech T[ack Rig Date Start/Finish .21211DZ 212 l lOZ Hammer WeighUDrop 140# I 30" Hole Diameter (in) ....4Jocbes g C ;; • o-.Q >. .., -0 . "' ~ ~.c ~]1 _, " Blows/Foot C. ~[ 1i s E 5'~ ~ ~ • T ~ "'"' ~£ 0 U) 0 !; "' DESCRIPTION {) 10 20 30 40 FIii Exposed aggregate asphalt. Brown, SAND and GRAVEL, few silt ---------- S-1 Quat'1lrnary Alluvium • .. ~ Medium stiff, moisl,~ray and brown, SILT, trace organics and loose, silly 4 SAND, with gravel ( USM) ' -5 f-No sample S-2 f- S-3 Saft, wet, dark brown and gray, SILT (Ml), with peat lenses to 2 inches -10 !hiol<. . ------ 2 ... , :,: ' Wet, gray, silty fine SAND {SM). ' -15 S-4 Saturated, gray, fine lo coarse SAND, wilh silt, little gravel (SP) • ;..., -20 20 Stiff, saturated, gray, SILT (ML). ---·--·----------· -·-·-21 S-5 Soft, saturaied, gray, SILT, with fine sand (ML). 0 ... , -25 0 Medium stiff, saturated, PEAT (Pn. ' S-6 Very soft, saturated, gray, SILT, with fine sand and organics (ML) 0 -30 0 0 0 . S-7 Very soft, saturated, gray, SILT (ML), wi!h fine sand and peal stringers. 0 .. , -35 0 Medium stiff, saturated, dark brown, PEAT (PT). ' S-R lnterbedded medium stiff, saturated, gray, SILT, with fine sand and woody ' .. Sampler Type (ST}: [D 2~ OD Split Spoon Sampler (SPT) 0 No Recovery M -Moisture Logged by; SGS II] 3" OD Split Spoon Sampler (D & M) I] Ring Sample '¥. Waler Level () Approved by: ~ Grab Sample 0 Shelby Tube Sample .!. Water Level at time of drilling (ATD) ti ~ a £ 0 A5soci.ated Earth Sciences, Inc. Exnloration Loa 1:~ [E ~ ~ m Project Number I Exploration Number I Sheet . ' KE070040A EB-5 2 of 3 Project Name ~ew TtaosP.ortation Center Ground Surface Elevation (fl) Location Beo!on WA Datum J,/" Driller/Equipment BorteQb Track Big Date StarUFinish 2l21lDZ 2l2:1l0l. Hammer WeighlfDrop 110# I 3Q" Hole Diameter (in) 4iacbes C ~= • g w o-0 ;; .e, -0 =:g • ,e Blows/Foot {". ~ .c _., w £ ~ e[ •-~ ~ ~ s E ;: ~ .B..Q a • T • C>"' ~"' ,S 0 U) 0 DESCRIPTION u 0 10 20 30 40 PEAT (MUPT). 2 3 ! S-9 Saturated, gray, fine to medium SAND, with organics, and SILT stringers, 7 .. , -45 stralified (SP) 12 14 S-10 Gray and black interbedded SILT (laminated with very thin peat stringers) 5 ~,, · 50 5 Silty SAND, with organics and PEAT lenses to 3 inches thick (MUSM/PT) 6 S-11 Saturated, brown, silty fine to medium SAND, with peat lenses and wood • -55 (SM) 5 .,, 5 --Satura1ed....9I§t,_Slli with fine sand (Ml,.). -· ----·------ S-12 Saturated, gray, fine to medium SAND, with sill (SP). 0 .. 7 ~ 60 12 15 S-13 5 "'" ~ 65 --6 lnterbedded, saturated, gray, silty fine SAND and sandy SILT, wlth peat ' stringers, stratified (SM/ML). S-14 Saturated, gray, fine to medium SAND, with silt, slratlfied (SP) 0 -70 5 •10 Gray, SILT, with peat seams to 3 mm thick (Ml) ---5 ~ Saturated, gray, fine to medium SAND, silt grading to fine SAND, with slit, S-15 trace organics, weak stratification (SP). -75 9 .. ,. 16 " e • c:::_1~ Saturated, gray, fine to medium SANO, weakly stratified grading to SILT. " i Sampler Type {Sn: ~ DJ 0 No Recovery ~ 2" OD Split Spoon Sampler {SPT) M-Moisture logged by: SGB " OJ 3" OD Split Spoon Sampler (D & M) I] Ring Sample '?. Water Level () Approved by: g ©I Grab Sample 12] Shelby Tube Sample~ Water level at time of drilling (ATD} < ----·-- Associated Earth Sciences, Inc. Exploration Loa ~ w ~ ~ m Project Number I Exploration Number I Sheet -' KE070040A EB-5 3 of 3 Project Name bJew Iransportatioo Ceoter Ground Surface Elevation {ft} Location Renton WA Datum ..bl/A___ Driller/Equipment Bortech Track Rig Date Start/Finish 2l2HOI 2l2HD1 Hammer WeighUDrop 140#/ 30" Hole Diameter (ln} 4 iocbes g C ~: " • u- =~ • -o ~~ " ~,, Blows/Foot • ,s Q_ o_ E •-• ! t- Q_ s E ~~ :::i • • T m ""' ~ co 5 0 "' 0 DESCRIPTION () 10 20 30 40 J r--~tb.Ji.!l~~~.l!dJS_e/Ml,L --14 17 Bollom of exploration bo1fog al BO 5 feet Ground waler al 10 feet No heave -85 -90 -95 -100 i-105 110 . -115 ' Sampler Type (ST). [!] 2" OD Split Spoon Sampler (SPT) 0 No Recovery M-Moisture Logged by: SGS [D 3" OD Split Spoon Sampler (D & M) I] Ring Sample 51-Water Level (} Approved by: li'll Grab Sample IZ] Shelby Tube Sample l: Waler Level at time of drilling (ATD) ~ ~ i ~ ,-----------------.--------------,=--:----c---c·------·------·--··-Exoloration Log Project Number I Exploration Number '---i,------~s'"h-ee-ctc-------l KE070040A EB-6 1 of 3 -----~----------~------------! Associated Earth Sciences, Inc. Project Name New Transportation Center Location Renton WA Driller/Equipment Bortech Track Rig HammerWeight/Drop _1~4~0~#=/~3~0~"------------------- cs -• %. a. s E • T m 0 U) 1--- S-1 S-2 ,YO ~D @' [ """ DESCRIPTION Fill Exposed aggregate asphalt/gravel surfacing Moist, silly SAND, cuttings, with gravel Quaternary Alluvium Soft, moist, brown, sandy SILT, with thin fine sand seams (Ml). Saturated, red-brown, fine SAND. with silt and gravel (SP) Ground Surface Elevation (ft) Datum ..J"'W'""--------- Date Start/Finish 21711D7,2/?1/Q7 Hole Diameter (in) ~4~io~cwbc,P=S------ Blows/Foot 10 20 30 40 --------------------------------- ~ 15 S-3 -20 S-4 "25 S-5 ~ 30 S-6 r 35 S-7 Very soft, saturated, gray. clayey SILT, few gravel and grades to sandy silt at 15 feel (ML-MH) Saturated, gray. silty fine SANO, with gravel, weakly stratifted (SM) Soft, interbedded, saturated, gray, SILT and fine to medium SAND, wilh sill (SM/SP) Saturaled, gray, medium to coarse SAND, few gravel, trace sill (SP}, non-stratified. Wet, gray and brown, SILT, with peat stringers (stratified) (ML) Saturated, gray, silty medium lo coarse SAND grading to gray and brown, interbedded Sil T, with fine sand and PEAT {SM/PT/ML) 0 7 12 0 ' 0 0 J 19 & c-0 Saturated, gray, fine to coarse SAND, few silt, trace gravel {SW) and O ..t.. ;f----,S,-a.Lrn!JpLle"r"!Tclyp-e-(~Sc!T)~----------------c._ _ _:__:_ ____ L.....J....L.L.,..,_L._L._L_L_L...!.....j ·o~ I] D ,-2" OD Split Spoon Sampler (SPT) No Recovery M -Moisture i OJ 3" OD Split Spoon Sampler (D & M) I] Ring Sample Sl. Water Level () fil ~ Grab Sample (2J Shelby Tube Sample.?-Water level at time of drilling (ATD) ·~----------------------------------------------------' Logged by: SGB Approved by: I Associated Earth Sciences, Inc. Exnloration Loa 1,~~J [!fil ~ ~ ~ Project Number I Exploration Number I Sheet . KE070040A EB-6 2 of 3 - Project Name ...!'ml!LI@M/lortation Cianter Ground Surface Elevation (ft) Location Beoton WA Datum _bi" Driller/Equipment Bortech Track Rig Date StarUFinish 212J /OZ 212J /OZ Hammer WeighUDrop 140# 130" Hole Diameter {in) A.in.cl-.-- g C j = "' • u-0 • ·-0 =~ .3~ ~ ~D Blows/Foot • ~ o. E ~c " ~ .... 1i s E ~~ ,: E • 0 " • • T • (!}<I) ~ffi ~ 0 <I) 0 DESCRIPTION 0 5 10 20 30 40 occasional silt seams, weakly stratified. D 4 ~ 45 Couple feel of heave/fell out. 2nd try failed again -no sample. Gravels and harder drilling reported by driller 45 lo 49 feet S-9 Saturated, gray, silly SAND (SM), with grave! grading lo gray, silty fine D -50 SAND, wilh lenses of peal and sill 4 •10 6 Saturated _g.@Y fine Ip medium SAND !rrni!USP\ Saturated, gray, SILT, with fine sand and lenses of peat and chunks of ~ 55 wood (ML) S-10 6 "-12 s ' -----------· ------------------~ ------ S-11 Saturated, gray, fine to medium SAND (SP), trace silt D .. , L 60 Saturated, gray, SILT, with fine sand and peat stringers (ML). D 3 S-12 Jnterbedded, saturated, ~ray, fine to medium SAND, with silt and stratified 7 ... ,. '-65 sandy SILT, with very Ihm peat slringers (Ml1SM) 7 ' S-13 Same as above D ~ 70 2 "• 2 ~ S-14 Wet, gray, SILT, stratified, with fine laminae or peat, lenses of peat to ' J.. B L 75 1·inch thick, and trace organics (Ml) 6 12 a k_,. Saturated, fine to medium SANO, with trace silt grading to silty fine SAND ' Sampler Type (ST). (D 2" OD Split Spoon Sampler (SPT) 0 No Recovery M -Moisture Logged by: SGB []] 3n OD Split Spoon Sampler (D & M) I] Ring Sample Si Water Lever {) Approved by: IQ/ Grab Sample IZ) Shelby Tube Sample .!. Water Level at time of drilling (ATD) ~ £ • ' - Associated Earth Sciences, Inc. Exoloration Log ~ [iJ ~ ~ ~ Project Number I Exploration Number I Sheet ·. KE070040A EB-6 3 of 3 --- P1oject Name New Trans11ortation Center Ground Surface Elevation (ft) Location Rentoo WA Datum J\lih Driller/Equipment Bortech TrnQ~ Big Date Start/Finish 2l2jLQZ 2l2HOZ Hammer WeighVDrop 140#/ 30" Hole Diameter (in) A.incbes g C ~: ~ a u- =~ -o ID '£ ~ ~~ Blows/Foot ID ~ ~[ -' a ,.. ID-" . a. s E ~~ 2 _Q ~ ID ~ """ 0 T U) 0 ~ 00 5 DESCRIPTION <) 10 20 30 40 (SPISM) 7 12 -85 S-16 Saturated, gray, silty fine to medium SAND. very weakly stralified, trace organics (SM) 8 14 ... , 21 "-90 _YJLeJ,_grny~_!iilly_Ji!n;1_~AND weakly_straUfi..e_d.,_ __ S-17 ·---·---------' ..... 15 Bo':tom of exploration boriog at 90 5 feet 23 Grouod waler at 10 feel "-95 '-1DO -105 1-110 - -115 Sampler Type {ST): ill 2~ OD Splil Spoon Sampler {SPT) 0 No Recovery M -Moisture Logged by: SGS ill 3" OD Split Spoon Sampler {D & M) I] Ring Sample SL Water Level () Approved by: IQJ Grab Sample lZ) Shelby Tube Sample X Water Level at time of drilling (ATD) Associated Earth Sciences, Inc. Date Sampled Project Project No. 2/22/2007 Renton Transfer Station KE070040A Tested By Location EB/EP Nol°epth MS Onsite Sample t.D. EB-3 25-200' EB-3 20' Wet Weight 902.2 1041.6 Dry Weight 822.4 903.7 Water Weight 79.8 137.9 Pan 5128 510.9 Actual Dry Weight 309.6 392.8 Percent of Water Weight 25.8 35.1 After Wash Weight 639.1 710.5 Percent Passing #200 59.2 49.2 Sample I.D. EB-3 45' EB-3 25' Wet Weight 773.2 956.7 Dry Weight 734.3 781.1 Water Weight 38.9 175.6 Pan 51S.4 4104 Actual Dry Weight 215.8 370.8 Percent of Water Weight 18.0 47.4 After Wash Weight 707.6 521.2 Percent Passing #200 12.4 70.1 Sample 1.0. EB-3 5-200' EB-3 10-200' Wet Weight 921.2 633.3 Dry Weight 830 3 614.0 Water Weight 90.9 19 3 Pan 392.9 314.9 Actual Dry Weight 437.5 299.0 Percent of Water Weight 20.8 6.5 After Wash Weight 633.5 601.6 Percent Passing #200 45.0 4.1 Percent Passing #200 ASTM D 1140 Soil Description Various EB-3 35' EB-3 40' 668.1 531.1 592.3 4884 75.8 42.7 297.2 312.1 295.1 176.3 25.7 24.2 532.2 451 7 20.4 20.8 EB-3 15-200' EB-3 30' 897.8 839.2 831.5 6596 66.4 179.6 521 0 33Ul 310.5 327.7 21.4 54.8 816.9 389.6 4.7 82.4 ASSOC/A TED EARTH SCIENCES, INC. 911 51h Ave., Suite 100 Kirkland. WA 98033 425-827~7701 FAX 425-827-5424 APPENDIXD Bond Quantities, Facility Summaries, and Declaration of Covenant (not included at this time) COUGHLIN PORTER LUNDEEN Renton School District Transportation Center APPENDIX£ Operations and Maintenance Manual (not included at this time) I COUGHLIN PORTER LUNDEEN Renton School District Transportation Center