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Home My WebLink AboutWatershed Modeling Analysis - PLN General - 10/4/2010 APPENDIX A: WATERSHED MODELING ANALYSIS Union River Restoration Runoff Volume Analysis October 2010 Revised 10/4/2010 Prepared by 0 n ertiou-s Systems, Inc. PO Box 30188,Seattle WA 98113 (206)784-7175 For ESI ESA Inc.210 NE Cherokee Beach Road,Belfair,WA 98528 Page 16 i Table of Contents Table of Contents Tableof Contents.......................................................................................................xvii Tables.........................................................................................................................xvii Summary...................................................................................................................... 18 Introduction................................................................................................................. 19 Data.............................................................................................................................. 19 WatershedN-1, DSN 801..........................................................................................20 WatershedN, DSN 802.............................................................................................20 WatershedM, DSN 803.............................................................................................21 SCS Event based comparison.......................................................................................22 DataValidation............................................................................................................23 PeakRunoff Rates........................................................................................................25 Tables Table 1-Summary of Runoff Volumes for 2 year event............................................................................ 18 Table 2-Recommended Storage Requirement......................................................................................... 18 Table 3-Project Data,Areas,Landuse and CNNumbers....................................................................... 19 Table 4- Watershed N-1, HSPFAnalysis................................................................................................ 20 Table S- Watershed AT, HSPFAnalysis........................................................Error!Bookmark not defined Table 6-Watershed M, HSPFAnalysis........................................................Error!Bookmark not defined Table7-Precipitation Values................................................................................................................ 23 Table 8-2 year 24 hour Volume Comparison......................................................................................... 24 Table9-Peak runoff rates..................................................................................................................... 25 Summary Union River Restoration encompasses 165.8 acres at the foot of Union River and Hood Canal. This analysis primarily concerns itself with the volume of runoff generated from the site resulting from the 2 hour through 6 hour duration,two year return frequency flood event. 2 year return frequency runoff volumes Peak 5 hr vol Interval 2 hr dur 3 hr dur 4 hr dur 5 hr dur 6 hr dur 24 hr dur 5(S Rate of 24 hr Based 100yr 0.8087 1.0979 1.3411 1.5545 1.763 3.943 Volume event precip(in) HSPF Vol(ac- Vol(ac- Vol(ac- Vol(ac- ft) Vol(ac-ft) Vol(ac-ft) Vol(ac-ft) ft) Vol(ac-ft) ft) ft) WaterShedN- 2 year 0.604 0.8496 1.0753 1.2816 1.4748 3.1925 1 HSPF scs 0.1816 0.3464 0.5067 0.6590 0.8159 2.6865 1.8215 1.5312 WaterShedN HSPF 2 year 1.3616 1.9123 2.4056 2.8417 3.2483 6.9688 Scs 0.4726 0.7518 1.0353 1.3115 1.6011 5.2641 3.3695 3.0798 WaterShedM HSPF 2 year 3.8198 5.2682 6.5222 7.5945 8.6551 17.4393 Sc5 1.1576 1.4489 1.9270 2.4936 3.1626 14.6832 8.8481 9.1780 Table 1 -Summary of Runoff Volumes for 2 year event. We recommend that Union River Restoration storage requirements are based on the volumes estimated using HSPFToolkit. For the entire 165.8 acres,the total volumes for each duration event are: r(ac- (ac-ft)du t hr dur(ac-ft) 3 hr dur(ac-ft) 4 hr hr du 5 hr dur(ac-ft) 6 hr dur WaterShedN-1 0.604 0.8496 1.0753 1.2816 1.4748 WaterShedN 1.3616 1.9123 2.4056 2.8417 3.2483 WaterShedM 3.8198 5.2682 6.5222 7.5945 8.6551 Total 5.7854 8.03 10 11.718 13.3782 Table 2-Recommended Storage Requirement ESA Inc.210 NE Cherokee Beach Road,Belfair,WA 98528 Page 18 Introduction The property is located in Belfair Washington where Union River converges with Hood Canal. A description of the property is provided elsewhere. This study evaluates the runoff from the site for the 2 hour through 6 hour, 2 year return interval event using HSPF and the SCS event models. The peak five (5)hours of the SCS 100 year return frequency, 24hr duration event is also computed. The two methods are compared because concern of volume estimates using an event model. In an event model when one specifies a return event,the event is based on the peak flow rate,which is acceptable for conveyance analysis. However,peak flow rate is not the same as peak runoff volume. HSPF is used because in Washington State time series of 40-50 years are available for most regions. The time series provide an accurate account of the volume of runoff that is generated. The issue with HSPF is similar to that of event models. When HSPF generally reports a return frequency based on Log Pearson Type III,it is again a peak flow rate. HSPFToolkitTM, by Engenious Systems, Inc. provided the tools necessary to convert the time series to a return volume frequency. It is possible to identify a probable 2 year recurrence volume of any duration. The 167.8 acre site is divided into three(3)watersheds labeled WatershedN-1,WatershedN,and WatershedM. While the watersheds are adjacent to one another,they are analyzed separately because each independently enters the proposed storage facility. Data The data was generated from design documents and applied to both models as follows: HSPF Landuse HSPF Event Model Designation Equivalent Impervious Area (ac) imp(ac) Pervous cn cn Area(ac) 11.7 0.9 D 88 10.8 SAT, Lawn, Flat Parking/Flat 27.5 2.5 A 39 3.8 A/B Lawn, Mod D pasture 88 14.4 SAT, Pasture, FLAT Parking/Flat D forest wetland 83 6.8 SAT Forest Flat 129.3 8.3 A lawn 68 16.4 A/B Lawn, Mod Parking/Flat A forest 55 62.9 A/B Forest, Mod ESA Inc.210 NE Cherokee Beach Road,Belfair,WA 98528 Page 19 D Lawn 89 2 SAT, Lawn Mod D Forest wetland 83 39.7 Sat, Forest Mod 168.5 11.7 156.8 Table 3 -Project Data,Areas,Landuse and CN Numbers For the HSPF model,time series were generated for each of the watersheds. WatershedN-1 was assigned a time series 801,WatershedN was assigned time series 802 and WatershedM was assigned time series 803. Using HSPFToolkit was then used to generate reports based on volume using Log Pearson for statistical summaries. The results of for each time series follow: WatershedN-1, DSN 801 Summary Return Freq by Log Pearson Type III 12 hr 1 day Interval 2 hr dur 3 hr dur 4 hr dur 5 hr dur 6 hr dur dur dur Vol {ac- Vol {ac- Vol (ac- Vol (ac- Vol (ac- Vol (ac- Vol (ac-ft) ft) ft) ft) ft) ft) ft) 2 year 0.604 0.8496 1.0753 1.2816 1.4748 2.2708 3.1925 5 year 0.7435 1.0644 1.3565 1.626 1.8772 2.974 4.3359 10 year 0.8249 1.1884 1.5154 1.8214 2.1001 3.3716 4.9991 25 year 0.9183 1.329 1.6921 2.0395 2.3432 3.811 5.7446 50 year 0.9824 1.4242 1.8096 2.1847 2.5017 4.1003 6.2418 100 year 1.0425 1.5125 1.917 2.3177 2.6441 4.3623 6.6962 Based on a times series interval of 60 minutes and assumption that time series is a runoff series(cfs) Table 4-Watershed N-1,HSPF Analysis WatershedN DSN 802 Summary Return Freq by Log Pearson Type III ESA Inc.210 NE Cherokee Beach Road,Belfair,WA 98528 Page 20 I Interval 2 hr dur 3 hr dur 4 hr dur 5 hr dur 6 hr dur 12 hr 1 daydur dur Vol (ac- Vol (ac- Vol (ac- Vol (ac- Vol (ac- Vol (ac- Vol (ac-ft) ft) ft) ft) ft) ft) ft) 2 year 1.3616 1.9123 2.4056 2.8417 3.2483 4.9924 6.9688 5 year 1.6922 2.4048 3.0555 3.641 4.1885 6.5393 9.4244 10 year 1.8911 2.6897 3.4247 4.0977 4.7283 7.4137 10.8444 25 year 2.1252 3.0133 3.8368 4.6097 5.3352 8.3804 12.4374 50 year 2.2894 3.2327 4.1113 4.9519 5.7419 9.0168 13.4983 100 year 2.4462 3.4367 4.3627 5.21 6.1159 9.59' 14.4668 Based on a times series interval of 60 minutes and assumption that time series is a runoff series(cfs) Table 5-WatershedN,HSPF Analysis WatershedM, DSN 803 Summary Return Freq by Log Pearson Type III 12 hr 1 day Interval 2 hr dur 3 hr dur 4 hr dur 5 hr dur 6 hr dur dur dur Vol (ac- Vol (ac- Vol (ac- Vol (ac- Vol (ac- Vol (ac- Vol (ac-ft) ft) ft) ft) ft) ft) ft) 2 year 3.8198 5.2682 6.5222 7.5945 8.6551 12.8064 17.4393 5 year 4.9811 6.7897 8.4553 9.8884 11.2923 16.9139 23.6013 10 year 5.7563 7.7305 9.5987 11.2495 12.8195 19.3135 27.2648 25 year 6.7467 8.8589 10.9172 12.8225 14.546 22.0421 31.4792 50 year 7.494 9.6626 11.822 13.9038 15.7081 23.8872 34.3555 100 year 8.2505 10.4395 12.6703 14.9188 16.7801 25.5948 37.0348 ESA Inc.210 NE Cherokee Beach Road,Belfair,WA 98528 Page 21 l Based on a times series interval of 60 minute$and assumption that time series is a runoff series(cfs) Table 6-WatershedM,HSPF Analysis The tables represent runoff in acre-feet for return intervals 2 through 100 year and event durations from 2 hour to 24 hours. This table is unusual in that the return frequencies are based on the recurrence of a runoff volume, not flow rate! SCS Event based comparison SCS runoff is a simple computation based on the equation: Q — (P —0.2S)Y�p +0.85) Where Q: Runoff in inches. P: Precipitation in inches. S: An equation based on the SCS CN number computes as: S = 100 0/CN- 10 Hence,given an area of 11.7 Acres with an SCS CN of 85: S = 100%S -10 = 1.7647 And if the precipitation is 4.5 inches: (4.5—0.2 -1,7647)' — 2.91 inches � — (4.5 +0.8x1.7647) What this means is that the runoff from 11.7 acres is: R = (2.91/12)11.7 = 2.84 ac—ft For an SCS comparison of runoff with HSPF,precipitation rates for equivalent duration runoff events are required. This information is not available from traditional sources for precipitation. HSPFToolkit was used to generate the precipitation volume return values that are equivalent to the volumes that were computed for each design duration in the above section. Theses precipitation values were then used in the SCS equation to estimate the SCS volume for comparison to actual data. Summary Return Freq by Log Pearson Type III ESA Inc.210 NE Cherokee Beach Road,Belfair,WA 98528 Page 22 Interval 2 hr dur 3 hr dur 4 hr dur 5 hr dur 6 hr dur 12 hr dur 1 day dur Vol Vol Vol Vol Vol Vol Vol (in/intv) (in/intv) (in/intv) (in/intv) (in/intv) (in/intv) (in/intv) 2 year 0.8087 1.0978 1.3411 1.5545 1.763 2.7027 3.943 5 year 0.9323 1.2781 1.565 1.8253 2.0914 3.2249 5.004 10 year 1.0059 1.3815 1.6965 1.9887 2.2911 3.5299 5.6678 25 year 1.0921 1.4991 1.849 2.1821 2.5287 3.8811 6.473 50 year 1.1524 1.5792 1.9547 2.3186 2.6973 4.123 7.053 100 year 1.2101 1.6541 2.0549 2.45 2.8601 4.3511 7.6189 Based on a times series interval of 60 minutes and assumption that time series is a precipitation(in) Table 7-Precipitation Values To determine if the predicted precipitation values are reasonable,we compared the HSPF precipitation value for the 100 year 24 hour event with the"standard" 100 year 24 hour precipitation value for the region. HSPF predicted a 100 year 24 hour precipitation of 7.62 inches. The value based on traditional SCS procedures is 5.37 inches. The conclusion is that we can used the HSPF values in the SCS equation,and if anything, it will over predict the runoff that an SCS rate based precipitation would compute. As can be seen in the Table 1, predicted SCS volumes for the various runoff durations are less than the values predicted by HSPF data. Data Validation Although direct comparison of runoff events for the two year 2 through 6 hour duration events are not really possible,we can compare the runoff volumes of the 2 year 24 hour rate based volume and also look at the volume of the peak 5 hours of the two year 24 hour event. The results are also included in Table 1 and repeated hear for convenience. 2 year return frequency runoff volumes Peak 5 hr vol 3 6 24 hr SCS of 24 hr hr dur Rate hr dur dur 100yr Based precip(in) HSPF 3.943 Volume event ESA Inc.210 NE Cherokee Beach Road,Belfair,WA 98528 Page 23 J Vol Vol Vol (ac- Vol (ac- Vol (ac- (ac- (ac- ft) ft) ft) ft) ft) WaterShedN-1 HSPF 3.1925 SCS 2.68651 1.82152 1.53123 WaterShedN HSPF 6.9688 SCS 5.2641 3.3695 3.0798 WaterShedM HSPF 17.4393 SCS 14.6832 8.8481 9.1780 Table 8-2 year 24 hour Volume Comparison While not completely uniform,the above table indicates that for WaterShedN-1 the predicted volumes based on four scenarios are: HSPFTooIKit 3.19 acre feet SCS using HSPFToolkit precip values: 2.69 acre feet Traditional SCS 2 year 24 hour event(rate based): 1.82 acre feet Peak five(5)hours of a traditional 100 year 24 hr event(rate based) 1.53 acre feet The predicted runoff volumes from HSPFToolkit are higher than prediction methods that rely on the area under the SCS Unit hydrograph design curve(Type 1A). We recommend reliance on the volumes predicted by HSPFToolkit because they are based on the recurrence interval of a volume which using the SCS design hydrograph is based on the recurrence frequency of a peak runoff rate, which is not the same and in fact,not a very good comparison. In order to use recurrence interval of a rate to predict volume,there must be a direct correlation between rate and volume. In fact,there isn't. A 100 year peak flow rate does not necessarily mean it rained more than a 10 year runoff event. 'Based on SCS Runoff equation using HSPFToolkit generated 2 year precipitation values. z Based on 2 year 24 hour hydrograph generated by StormShed3G. s Based on peak five(5)hours of a 100 year 24 hour hydrograph generated by StormShed3G. c Road Belfair,WA 98528 ESA Inc.210 NE Cherokee Beach , Page 24 Peak Runoff Rates The peak runoff rates that are expected from each watershed is summarized below: Summary Peak Flow Rates (cfs) 2yr24hr 100yr24hr WatershedN-1 SCS 3.8583 8.9688 HSPF 3.9149 7.0116 WatershedN SCS 5.5574 16.3993 HSPF 8.9452 16.6975 WatershedM SCS 8.9299 41.3006 HSPF 26.2147 53.703 Table 9-Peak runoff rates Rates were computed using Log Pearson Type III by HSPFToolkit,on peak year rates for the time series data. They are compared to similar values from StormShed3G. Both are based on the 24 hour duration event. HSPF predicts higher return rates. Of particular interest is the rate predicted by HSPF for the 2 year 24 hour period in Waterhshed M. This is probably a reflection of the designation of Type D soils that is forested and saturated,whereas in the SCS model,the area was designated as simply forested. ESA Inc.210 NE Cherokee Beach Road,Belfair,WA 98528 Page 25 APPENDIX B- CULVERT HYDRAULIC ANALYSIS UNION RIVER ESTUARY RESTORATION HYDRAULIC ANALYSIS - OF THE CULVERTS CROSSING ROSSEL ROAD NOTE THAT ROSSEL ROAD HAS MAJOR POWER LINES IT AND WE NEED TO STAY BELOW THEM. ASSUME THE POWER HAS 36" COVER AND THAT THE BOTTOM OF THE POWER LINES ARE AROUND ELEVATION 7.9 . THERE ARE SEVERAL 2' DIAMETER CULVERTS CROSSING ROSSEL ROAD ALREADY. I SUSPECT THEY ARE 2' DIA. SO THEY CAN GO UNDER THE POWER. THEREFORE WE WILL USE MULITPLE 24" CULVERTS TO CROSS ROSSEL ROAD. USE 2 24 WATERSHED M CULVERTS _ - EVERTS TO CARRY A 100 YEAR FLOW OF 54.7 CFS WATERSHED N = USE 1 - 24" CULVERT TO CARRY A 100 YEAR FLOW OF 17.8 CFS WATERSHED N-1 = USE 1 - 24" CUVERT TO CARRY A 100 YEAR FLOW OF 9 CFS ALL THE CULVERTS WILL ALLOW FISH PASSAGE AT THE 2 YEAR FLOW. SEE REPORT BY ENGENIOUS SYSTEMS FOR 2 AND 100 YEAR FLOWS FOR EACH WATERSHED. Entered Data: Shape ........................... Circular Number of Barrels ............... 1 Solving for ..................... Headwater ESA Inc.210 NE Cherokee Beach Road,Belfair,WA 98528 Page 26 Chart Number .................... 1 Scale Number.................... 3 Chart Description ............... HDP PIPE; NO BEVELED RING ENTRANCE Scale Description ............... GROOVE END ENTRANCE, PIPE PROJECTING FROM FILL Overtopping ..................... Off Flowrate ........................ 28.0000 cfs Manning's n ..................... 0.0130 Roadway Elevation ............... 10.9000 ft Inlet Elevation ................. 6.6000 ft Outlet Elevation ................ 6.0000 ft Diameter ........................ 2.0000 ft Length .......................... 150.0000 ft Entrance Loss ................... 0.8000 Tailwater ....................... 1.8000 ft Computed Results: Headwater ....................... 10.3948 ft Inlet Control Slope ........................... 0.0033 ft/ft Velocity ........................ 8.9127 fps Messages: Computing Inlet Control headwater. Solving Inlet Equation 26. Solving Inlet Equation 28. Headwater: 10.3948 ft ESA Inc.210 NE Cherokee Beach Road,Belfair,WA 98528 Page 27 DIS- HEAD- INLET OUTLET CHARGE WATER CONTROL CONTROL FLOW NORMAL CRITICAL OUTLET TAILWATER Flow ELEV. DEPTH DEPTH TYPE DEPTH DEPTH VEL. DEPTH VEL. DEPTH cfs ft ft ft ft ft fps ft fps ft 3.40 7.27 0.77 0.00 NA 0.70 0.64 3.48 0.70 0.00 1.80 6.80 7.61 1.11 0.00 NA 1.03 0.92 4.19 1.03 0.00 1.80 10.20 7.88 1.38 0.00 NA 1.33 1.14 4.58 1.33 0.00 1.80 13.60 8.12 1.62 0.00 NA 2.00 2.00 4.33 2.00 0.00 1.80 17.00 8.34 1.84 0.00 NA 2.00 2.00 5.41 2.00 0.00 1.80 20.40 8.55 2.05 0.00 NA 2.00 2.00 6.49 2.00 0.00 1.80 23.80 8.74 2.24 0.00 NA 2.00 2.00 7.58 2.00 0.00 1.80 27.20 8.93 2.43 0.00 NA 2.00 2.00 8.66 2.00 0.00 1.80 30.60 9.12 2.62 0.00 NA 2.00 2.00 9.74 2.00 0.00 1.80 34.00 9.31 2.81 0.00 NA 2.00 2.00 10.82 2.00 0.00 1.80 37.40 9.49 2.99 0.00 NA 2.00 2.00 11.90 2.00 0.00 1.80 40.80 10.16 3.66 0.00 NA 2.00 2.00 12.99 2.00 0.00 1.80 44.20 10.23 3.73 0.00 NA 2.00 2.00 14.07 2.00 0.00 1.80 47.60 10.15 3.65 0.00 NA 2.00 2.00 15.15 2.00 0.00 1.80 51.00 10.22 3.72 0.00 NA 2.00 2.00 16.23 2.00 0.00 1.80 54.40 10.44 3.94 0.00 NA 2.00 2.00 17.32 2.00 0.00 1.80 57.80 10.68 4.18 0.00 NA 2.00 2.00 18.40 2.00 0.00 1.80 ESA Inc.210 NE Cherokee Beach Road,Belfair,WA 98528 Page 28 Engineering services Associates, Inc. Friday, November 03, 2006 Neil Werner Executive Director Pacific Northwest Salmon Center PO Box 3238 Belfair, WA 98528 Subject: Soil Log Report for the property currently owned by Jack Johnson Dear Neil, Pursuant to my contract with the Pacific Northwest Salmon Center I am submitting my findings from m soils exploration of the Jack Johnson Property. In m ro proposal h y py p p to the PNSC Board I proposed digging 30 soil pits on the property. This work was done to: 1. Map the surface soil characteristics of the 90 acres site. 2. Determine the level of the water table on the site at the conclusion of the "dry" season. 3. Obtain data and information to support the upcoming wetland delineation for the property. 4. Obtain data and information to support the upcoming archeological study of the property. 5. Evaluate the engineering properties of the on site soils to determine their suitability for excavation, fill, wetland and pond construction, building foundations, and on site waste water disposal. Procedures: I visited the site on October 25t" and 26t" with a backhoe and dug 30 soil pits. The soil pits had previously been staked by AEC Consultants of Silverdale. A map of the soil log layout is included with the report (See Figure One). Generally the soil logs were dug to a depth where it appeared that there would be no significant changes in the soil profile. The deepest soil log was dug 6 feet deep. The soil was visually classified, by layer, using the Unified Classification System (UCS). (A UCS table has been included with this report for the review by the reader.) Photos were taken of several of the soil (logs. Several of the soil log gphotos have been included with this report) Generally, the soil logs on the West side of Roswell Drive were similar so we included a "typical" soil log photo represent all the soil logs west of Roswell Drive. The weather during the soil testing was dry and we were able to drive to most of the soil pit locations with an automobile. There had been a couple of small rain storms in October before the excavation of the soil pits. October was a dry month at the end of dry summer and fall. Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 1 FAX(360)277-3187 I Engineering Services Associates, Inc. A Brief Site History: The Jack Johnson Property is approximately 90 acres in size. The property was developed as a dairy farm in the 1920's by the Roessel family. In the 1930's the Army Corps of Engineers constructed the dikes. Over the last 70 years the primary use of the property has been as a dairy farm and for animal husbandry. Hay has been the primary crop. The soil on the property has been disked and furrowed on numerous occasions. The drainage ditches on the property were constructed by the Roessel family. Jack Johnson bought the property in the 1980's. In 1994 Johnson's installed a new tide gate structure and drainage outfall. The existing 30 CMP drainage pipe was lined with a 22 inch diameter plastic pipe and a new tide gate was installed. The entire property drains to southwest corner of the property. Site Description: It lies at the bottom of the hill on the west boundary of the Belfair Urban Growth Area and borders Lynch Cove and Hood Canal on the east. The entire western boundary of the property has been diked to prevent salt water intrusion. The property is drained by a matrix of deep — up to 7 feet deep — drainage ditches that drain through tides gates to Hood Canal. The property has been actively farmed for over 50 years. All the areas where soil logs were dug are being actively farmed. (SEE FIGURES 1, 2, and 3.) The elevations on the site vary from elevation 8 MLLW at the Southwest corner to elevation 18 MLLW at the Jack Johnson residence. (SEE FIGURE 4). - FIGURE 1: THE JOHNSON FARM PROPERTY LOOKING NORTH — FALL 2006 Engineering Services Associates Inc. 210 N.E.Cherokee Beach, Belfair,Washington-98528 (360)275-7384 2 FAX(360)277-3187 f Engineering Services Associates,, Ina e r a ydrf � I � r JC k FIGURE 2: THE JOHNSON FARM PROPERTY LOOKING SOUTHWEST— FALL 2006 Site Soil Characteristics: This soil investigation began by reviewing the Soil Conservation Service (SCS) Soil Mapping for Mason County. The SCS soil type boundaries are shown on Figure 1. We did not find a close correlation with the SCS soil typing of the site and the soil testing. Virtually all the soils on the site were either top soil, silty sand, or sandy silt. The was not a rock to be found in any of the soil logs except where gravel had been imported at some previous time. We did not find any "Tidal Marsh" soils that are shown on the SCS Soil Mapping. It was expected that the Tidal Marsh soils would be the remnants of the silty, organic mud present is Lynch Cove. Why we did not find any Tidal Marsh "type" soils is a mystery. We assume that the continuous tilling and grading of the soils to grow crops has had a major impact on the structure of the soil on the site. Several of the soil pits in the southwest quadrant of the property had a layer of clam and oyster shells at depths of 3 to 4 feet. Soil Pit No. 7 had a little gravel mixed in the shells. Please refer to Figure 3 and to the enclosed soil Test Pit Logs for a description the soil types present on the property. Figure 2-A below illustrates the typical soil pit for the portion of the Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 3 FAX(360)277-3187 Engineering Services Associates, Inc. property west of Roessel Drive and for most of the property east of Roessel Drive. In the soil pits near the eastern boundary of the property the deeper soils changed in color to gray and the water table was higher. See Figure 2-B. A Jr At i FIGURE 2 A — TYPICAL SOIL PIT FOR THE MAJORITY OF THE PROPERTY wty, Yam^, FIGURE 2 B — SOIL PIT NO. 28 NEAR THE EAST BOUNDARY OF THE PROPERTY NOTE THE GRAY SILT SOILS AND THE WATER IN THE BOTTOM OF THE PIT Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 4 FAX(360)277-3187 Engineering Services associates, Inc. SECTIONS 29, 3l, AND 32 T 23 N, R 1 W, WM At Y. r e k. � •1',1f t �S•: n r IW*Q . 4 2S� j 29i. Q . SCS SIB • G .x l f 2 • 0 21 .r:Mr • 1? - • .+/ I 23 • �D1 7 o 1 .PPROXNATE 7 612MUMMY OF 1 �' JACK 10HN 4 . PROPERTY 1 - • �c'W� JJ r ' CMAMIELS ffi.YYR .r►TDALVANE WALKWO TRAIL TIDAL '_ Cl' ��, ��a •� r9� MARSH ) J THELER WETLANDS a I -17 i A ,� +•fir. f�.. !1 tY J �. rr -SCALE: F-500' FIGURE 3 PACIFIC NORTHWEST SALMON CENTER AERIAL PHOTO AND SOIL PIT LOCATIONS Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 5 FAX(360)277-3187 Engineering Services Associates, Inc. Water Table: The depth of the water table is of major interest in that it is proposed to revert approximately 40 acres of western portion of this site back to medium to high salt marsh. It is also proposed to convert the northeast portion of the site into wetlands to treat the storm water for the Belfair UGA. Salt marsh habitat in this part of Hood Canal varies in elevation from 8 MLLW to 13 MLLW. The depth of the water table is shown in each of the soil pit logs. It varied from 2 feet to 3.5 feet. Site Topography and Salt Marsh Habitat: Figure 4 illustrates the elevations zones on the property. They elevations on the property range from elevation 6 MLLW datum to elevation 28 MLLW datum. The area within several elevation ranges is shown on Figure 4. The extreme high water at the end of Hood Canal is approximately elevation 15 MLLW. Extreme high water occurs when the winter high tides combine with low barometric pressure, localized flooding from the Union River and elsewhere, and high wind waves. The Federal Emergency Management Administration (FEMA) requires that first floor home elevations be constructed 2 feet above extreme high water. The main residence and garages on the property have a floor elevation above 18 feet. The secondary residence located at the north end of Roessel Drive has a floor elevation of 15 feet. The north barn has a floor elevation of 16.5 feet. All these elevations are based on the aerial survey and will need to be verified in the field by survey. Salt marsh habitat is defined "approximately" by low, medium, and high salt marsh habitat. The different salt marsh habitats often have significantly different vegetation. Low salt marsh varies from elevation 8 to 9.5 feet, medium salt marsh from elevation 9.5 to 11 feet, and high salt marsh varies from elevation 11 feet to 13 feet. Some researchers may include an elevation zone of 13 feet to 14 feet where "salt tolerant" vegetation is often present. The existing property has 31.2 acres below elevation 13.0 MLLW. When sections of the dike are removed salt water will flood the property and the areas of the property below elevation 13.0 will revert to salt marsh habitat. Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 FAX(360)277-3187 I Engineering services Associates, Inc. SECTIONS 29, 31, AND 32 T 23 N, R 1 W, WY Away _e �. A, APPRCLIGIM E- BOt/NDARY OF 1i' JACRJOHNSON r PROPERTYEXISTING ., 4Y'.,:tea/ •' (T DRAINAGE r' �f� R► ya CHANNEL8 Wm rrn Tnv.cuge ,.�« ♦ - THEtHt �' / f' � WALIONG r ' TRAIL MIER WETLANDS R=ge EL.Beg. EL.End. Ares(Acres) Percent Color 1 6.00 8.00 2.02 2.4 Red 2 8.00 9.00 1.14 13 Yellow 3 9.00 10.00 1.61 19 Green 4 10.00 11.00 5.66 6.6 Cyan 5 11.00 12.00 9.70 113 Blue 6 12.00 13.00 11.11 13.0 Magenta 7 13.00 15.00 29.47 34.4 Black 8 15.00 20.00 24.85 29.0 Gray FIGURE 4 SCALE: P-50V PACIFIC NORTHWEST SALMON CENTER SITE TOPOGRAPHY Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 FAX(360)277-3187 Engineering services Associates, Inc. The Proposed Improvements to the Property: There have been several concepts put forth for the development of the Pacific Northwest Salmon Center. The analysis and selection of a "preferred" alternative will depend on the recommendations set forth in this report and additional study of the site. Bruce Dees and Associates is waiting for the soils information, wet land delineation, and storm water treatment concept plan before developing a suite of final site concepts. The PNSC Board has selected the Concept C shown below for further development. Concept C will be used to discuss the engineering properties of the soils and to make design recommendations for fill, roadway, pond and building construction. CONNECTION TO PACIFIC NORTHWEST SALMON CENTER ___ THELER WEILAlR)TRAIL9 AND HOOD CANAL DIKE DRTiACH W/ SITE DEVELOPMENT CONCEPT C 71141o6 r1% = ;�` TRAIL ON ELEVAT6DPHF8 PREPARED FOR: NEW DIKE TO PROTECT \ ' PACIFICNORTHWESTSALMONCENTER P6OPERTTPROKI HIGH TIDE9 BELFAIR,WASHINGTON PREPARED BY.• RR l r.( h PROPERTVTOBEA ',, _ R'"ltik Jj i TO SALT MAKSH ANO`N-—J CONNECTIONTO WBTLAND HABITAT BRUCEDEES&ASSOCLITES ':�T"' I/: SALMON CENTER - LANDSCAPEARCHITECTS i '.I.r t, nAn,sysTRM TACOMA,WASHINGTONr _ 17 OO ❑ [[((��((]]((•• rC` l \��•,l ` � 'iJ' PRPTO A TO BE RENRNFDJ F�• /f \ CJ 1 \�\ :I! TO SALT NARSH AND /� PROPOSED OPEN SPACE �.' \ \ .. \,� i�."•, W6nAND HABITAT / Errs TSR3 s �♦`` - y ,r 9xia' ' AT S'R3 APxTRV DRnE MH+ COMPORTSTATTON •I .'� � ::'d _\\\��\��`� 1 J -X�j� l�� •:•' ADMHVISITtA77VE OFFIM �'' ` '' CONNECTION TO .. SALMON CENTER / =' • �i TRAIL Sl REM PROPOSED I /' `•.Q' {� DETENTION 1� PONDS ; �._ i NEWDIKETOtHIO1F.C-t �[I FROM wcn nueA DIRE BR Q ` TRAIL ON ELEVATED PILES 4 �I TVAL.ir TOCONNPCTION TO � WU ODRNTERRb WATER QUALITY LAB FUTURE SALMON SALMON `� ACCESS T'D UNION RIVIIR ' � ��' '` ^_`_��'�'��. /y C XMR EXPANSION iiWL A - STREAM i.\:ti I•'/• AND H(IOD GNAL CLASSROOMS RESEARCH TBAD. _ r FUTURE STORM WATER TREATMENT PONDS Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 8 FAX(360)277-3187 J Engineering Services Associates, Inc. Storm Water Treatment Ponds: It is proposed to construct 3 to 5 acres of storm water treatment ponds in the north east quadrant of the site. These ponds would consist of the storm water settling pond (Pond 1) that is be constructed so as to provide a four foot deep (water depth) one acre pond to remove sediment from the storm water (also referred to as the pretreatment pond). The second pond or ponds will consist of 2.5 to 4 acres of ponds (Pond 2) constructed so as to encourage wetland plant development. The depth of these ponds will vary from 2 feet in deepest portion to a shallow littoral zone along the shore line. The average water depth in the wetland treatment pond — or ponds - would be approximately 1.5 feet. All the ponds would hold water at constant depth. Water quality treatment in Pond 2 would be via the natural processes of further sedimentation and the uptake of the nutrients in the water by the wetland plant community. Note that detention is not a requirement for the proposed storm water treatment system since the ponds will discharge directly to Hood Canal via tidal channels. The area where the storm water treatment ponds are proposed is covered with a thick layer of top soil and tan colored sandy silt that is well aerated to a depth of approximately 2 feet. Below that elevation the soil turns to gray, wet silt with some clay. The water table in the area where the storm water treatment ponds are proposed was at an average depth of 2 to 2.5 feet when the soil pits were dug. These silty soils are moisture sensitive and construction should be completed under the driest conditions practical. Lenses of ground water were found in soil pits 29, 30, and 27 near the bottom of the pit. The following approach is recommended to construct the proposed storm water sedimentation and treatment ponds. 1. A four foot deep dewatering trench should be dug around three sides of the construction area. The ditch should be pumped or drained by gravity to the Mindy Creek or the surrounding wetlands. 2. A "hog fuel' access road for equipment access should be constructed into the excavation area. Excavation should begin at the north and east ends of the ponds. The ponds should be dug to grade as the excavation proceeds. The surface of the pasture should not be disturbed prior to the start of excavation. 3. A geo-textile fabric should be placed on the bottom of the sedimentation pond — Pond 1 — and six inches of bank run gravel placed over the fabric. To the greatest extend possible, the grass sod and top soil should be saved for use in creating the organic soils required to line Pond 2. 4. The water quality treatment pond should be over excavated by six inches and covered with six inches of organic soils. Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 9 FAX(360)277-3187 Engineering Services Associates. Inc_ Salt Marsh Construction It has been proposed to lower the grade of approximately 10 acres of the property west of Roswell Road to increase the area and quality of salt marsh on the property. The limits and depth of excavation have set to be determined. The soils found on the west side of Roessel Drive are moisture sensitive but could be used to future pasture land, parking lots, and recreation areas. The following approach is recommended for the excavation of the salt marsh areas. 1. Construct or reconstruct the proposed tidal channels. 2. Strip and save the sod and top soil from the areas to be excavated for use in the fabrication of the organic soils for the wetland storm water treatment ponds. 3. Excavate the salt marsh areas to grade. 4. Till and prepare the proposed salt marsh areas for natural recruitment of salt marsh plants from the surrounding areas. Roads and Parking Lots Areas where roads and parking lots are proposed should constructed as follows: 1. Strip the sod and top soil from the area and save it for construction of organic soils to be used elsewhere on the site. 2. Import the native soils from the salt marsh excavation areas compact them using vibratory compaction. Water may be required. Grade to drain. 3. In the road and parking lot areas — place geo-textile on top of native soils. 4. Place six inches to eight inches of bank run gravel over the geo-textile and compact the gravel. 5. Pave with 4 inches of 1-1/4" minus crushed rock and 2 inches of asphalt concrete pavement. All work should be completed between April 15 and October 15. Building Areas: The existing soils appear adequate for support light building loads, however, it is recommended that soil borings of at least 30 feet in depth be taken in the location of proposed building foundations. The following preparations should be taken prior to constructing building foundations. 1. Over excavate building footing areas two feet and backfill with compacted gravel backfill. The width of the footing trench should be 2 feet wider then the building footing. 2. Footing and crawl space drains should be installed and drained by gravity to the nearest drainage ditch or stream. Engineering Services Associates Inc. 210 N.E.Cherokee Beach, Belfair,Washington-98528 (360)275-7384 10 FAX(360)277-3187 J Engineering Services Associates, Inc. TEST PIT LOGS Logged by Pat McCullough PE Excavated by Zephyrs' Inc. Approximate Unified Soil Classification was assigned based on field descri bons. No lab testing was done to confirm classifications. TEST PITS DUG ON October 25, 2006. Pat McCullough, PE recorded the soil logs Ron Griffey-Contractor Test Pit 1 - Dominant Unified Depth ft Particle Size Soil T e Description 0-4" TOP SOIL OL ORGANIC TOP SOIL-FIELD GRASS 4"-5' FINE SAND SM LIGHT TAN INORGANIC SILTY SAND DRY FOR THE TOP 3 FEET. CLAM SHELL LAYER AT 3.5 TO 4 FEET. Test Pit 2 Dominant Unified Depth ft Particle Size Soil T e Description 0-6" TOP SOIL OL ORGANIC TOP SOIL-FIELD GRASS 6"- 1'-6" SANDY SILT ML INORGANIC, TAN, SLIGHTLY CEMENTED SANDY SILT- DRY 1.5-5' SANDY SILT ML INORGANIC, BROWN, SANDY SILT WATER TABLE AT 3'-6" SHELL LAYER AT 3' Test Pit 3 Dominant Unified Depth ft Particle Size Soil T e Description 0-0.5' TOP SOIL OL ORGANIC TOP SOIL-FIELD GRASS .5'-3' SANDY SILT ML INORGANIC, TAN, SLIGHTLY CEMENTED SANDY SILT- DRY 3'-5' FINE SAND SM LIGHT TAN INORGANIC SILTY SAND WT=2.5, SHELL LAYER 3.5 TO 4.0 Test Pit 4 Dominant Unified Depth ft Particle Size Soil Type Description 0-1' TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 1'-2.5 FINE SAND SM LIGHT TAN INORGANIC SILTY SAND 2.5-4.0 MED. SAND SP MEDIUM GRAINED SAND-TAN 4'-5' SANDY SILT ML INORGANIC SANDY SILT- BROWN-WET WT=3', SHELLS AT 5' Test Pit 5 Dominant Unified Depth ft Particle Size Soil Type Description 0-0.5' TOP SOIL OL ORGANIC TOP SOIL-FIELD GRASS 1'-5' FINE SAND ism LIGHT TAN INORGANIC SILTY SAND WT=3',6" SHELL LAYER AT 4' Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 11 FAX(360)277-3187 Engineering Services Associates, inc. Test Pit 6 Dominant Unified De th ft Particle Size Soil T e Description 0-.5' TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS .5'-3.5' SANDY SILT ML INORGANIC SANDY SILT-TAN 3.5'-5' SANDY SILT ML INORGANIC SANDY SILT- BROWN WT=3', 4", SHELLS IN SOILS AT 3.5'TO 4' Test Pit 7 Dominant Unified Depth ft Particle Size Soil T e Description 0-.5' TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS .5'-6' SANDY SILT ML INORGANIC SANDY SILT-TAN WT=3' Test Pit 8 Dominant Unified De th ft Particle Size Soil T e Description 0-.5' TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS .5'-5' FINE SAND SM LIGHT TAN INORGANIC SILTY SAND WT=3', SHELLS IN SOIL 4'-4.5' Test Pit 9 Dominant Unified De Mth Iftj Particle Size Soil T e Description 0-.5' TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS .5'-4.5' FINE SAND SM LIGHT TAN INORGANIC SILTY SAND 4.5-5.5 SANDY SILT ML SLIGHTLY CEMENTED, LIGHT GRAY WT=2.5', SHELLS IN SOIL AT 5'-5.5' Test Pit 10 Dominant Unified De thAft Particle Size Soil T e Description 0-.5' TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS .5'-4.5' FINE SAND SM LIGHT TAN INORGANIC SILTY SAND 4.5-5.5 SANDY SILT IML LIGHT TAN SANDY SILT WT=2'-2.5', MOTTLING AT 1.5' Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 12 FAX(360)277-3187 II Engineering services Associates, Inc. Test Pit 11 Dominant Unified Description De th ft Particle Size Soil T e 0-5 TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS .5'-5' FINE SAND SM VERY LIGHT TAN INORGANIC SILTY SAND 5'-6' SANDY SILT ML INORGANIC SANDY SILT - BROWN WT=2'-2.5' Test Pit 12 In the meander of the old T Sheet River Bed Dominant Unified Description De th ft Particle Size Soil Type 0-.5' TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS .5'-5' FINE SAND SM VERY LIGHT TAN INORGANIC SILTY SAND WT=3' Wet Sand - no visable water Test Pit 13 In the meander of the old T Sheet River Bed Dominant Unified Description Depth ft Particle Size Soil Type 0-.5' TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 0.8-2' SANDY SILT ML LIGHT TAN SANDY SILT 2'-5' SANDY SILT ML TAN TO BROWN SANDY SILT WT =2' Test Pit 14 In the meander of the old T Sheet River Bed Dominant Unified De th ft Particle Size Soil Type Description 0-.5' TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 0.8-2' SANDY SILT ML LIGHT TAN SANDY SILT 2'-5' SANDY SILT ML TAN TO BROWN SANDY SILT WT=3' SOIL WAS WET BUT NO STANDING WATER IN PIT Test Pit 15 Dominant Unified Description Depth ft Particle Size Soil T pe 0-0.7 TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 0.7-1.5' SANDY SILT ML LIGHT TAN SANDY SILT 1.5'-5' SANDY SILT ML GRAY SANDY SILT -SLIGHT ODOR-VERY WET SOIL Test Pit 16 In the meander of the old T Sheet River Bed Dominant Unified Description Death ft Particle Size Soil T e 0-1' TOP SOIL ML TAN SOIL NOT MUCH ORGANIC SOIL- ROOTS SILTY SAND SP TAN-SILTY SAND SOIL TOP 24"WAS MOTTLED WT=2' Test Pit 17 In the meander of the old T Sheet River Bed Dominant Unified Description Depth ft Particle Size Soil Type 0-0.5' ITOP SOIL 10L ORGANIC TOP SOIL- FIELD GRASS 0.5-5.5' ISILTY SAND ISP TAN- SILTY SAND SOIL-TOP 24"WAS MOTTLED WT=2' Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 13 FAX(360)277-3187 I Engineering services Associates, Inc. Test Pit 18 Dominant Unified De th ft Particle Size Soil T e Description 0-0.5 TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 0.5-1.5 SANDY SILT ML LIGHT TAN SANDY SILT- MOTTLED 1.5-4' SANDY SILT ML LIGHT TAN SANDY SILT 4'-5' SANDY SILT ML LIGHT GRAY SANDY SILT WT=3' Test Pit 19 Dominant Unified Depth ft Particle Size Soil T e Description 0-0.5 TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 0.5-1.0 PEAT OL BLACK PEAT LAYER 1-1.5 SANDY SILT ML LIGHT TAN COLOR 1.5 - 5' SANDY SILT ML GRAY SANDY SILT-WET, WT= 3' Test Pit 20 Dominant Unified De th ft Particle Size Soil T e Description 0-1' TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 1'-2' SILTY SAND SP TAN- SILTY SAND SOIL 2'-5' SILTY SAND SP BROWN -SILTY SAND SOIL WT=2' Test Pit 21 Dominant Unified De th ft Particle Size Soil Type Description 0-0.75 TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 0.75-2' SILTY SAND SP LIGHT BROEN -SILTY SAND SOIL 2'-5' SILTY SAND SP BROWN -SILTY SAND SOIL MOTTLED FROM 2' WT=3' WET SOIL Test Pit 22 Dominant Unified Depth ft Particle Size Soil T e Description 0-0.5 TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 0.5-1.5' SILTY SAND SP LIGHT BROWN SILTY SAND- MOTTLED 1.5'-3' SILTY SAND SP LIGHT BROWN SILTY SAND 3'-5' SILT ML GRAY SANDY SILT-WET, WT= 3' SOME ODOR Test Pit 23 Dominant Unified De th ft Particle Size Soil Tye Description p 0-0.5 TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 0.5-2' SAND SILT ML LIGHT BROWN 2'-4' SANDY SILT ML DARKER BROWN MOST 4'-5' SANDY SILT ML GRAY -ODOR-WT=4' Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 14 FAX(360)277-3187 I Engineering Services Associates, Inc. Test Pit 24 Dominant Unified Description De th ft Particle Size Soil Type 0-0.5 TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 0.5-0.9 GRAVEUSILTY GP- SP LOOKS LIKE AN OLD DRIVEWAY SAND MIX 0.9-1.7 SILTY SAND SP BROWN 1.7-3' SANDY SILT ML BROWN 3'-5' SILTY SAND SP GRAYISH BROWN -MOTTLED-WT=3' Test Pit 25 Dominant Unified Depth ft Soil Particle Size Ty Description 0-0.7 TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 0.7-2.7 SILTY SAND SP LIGHT BROWN - MOTTLED 2.7-5' SANDY SILT ML GRAISH TAN SILT WT=2.5' Test Pit 26 Dominant Unified Description De th Particle Size Soil Type ft 0-0.8 GRAVEL AND GP DRIVEWAY IMPORTED MATERIAL SAND IMPORT 0.8-3' SANDY SILLT ML GRAYISH BROWN - MOTTLED 3'-5' SANDY SILT ML GRAY-ROOTS TO 34", WT=2.8' Test Pit 27 Dominant Unified Depth ft Particle Size Soil Type Description 0-0.5 TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 0.5-1.5' SANDY SILT ML TAN 1.5-2.0' PEAT OL BLACK PEAT LAYER 2'-5' SANDY SILT ML GRAY-ODOR-WATER POURING INTO PIT-WT=1' Test Pit 28 Dominant Unified De th ft Particle Size Soil T e Description IMPORTED 0-2' BANK RUN GO BROWN - FREELY DRAINED GRAVEL AND SAND GRAVEL 2'-2.5' PEAT OL BLACK PEAT LAYER -6"THICK 2.5'-4.0' SANDY SILT IML GRAY -WET-WT=2.5' Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 )5 FAX(360)277-3187 Engineering Services Associates, Inc. Test Pit 29 Dominant Unified Description Depth ft Particle Size Soil Type 0-0.5 TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 0.5-5' SANDY SILT ML TAN - ROOTS AND WORMS TO 3.5' WT=3' WATER POURING INTO PIT Test Pit 30 Dominant Unified Description Depth ft Particle Size Soil Type 0-1' TOP SOIL OL ORGANIC TOP SOIL- FIELD GRASS 1'-5' SANDY SILT ML TAN - MODDLED 5'-6' SANDY SILT ML GRAY WT=2.5 FEET. Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 16 FAX(360)277-3187 Engineering services Associates, Inc. ♦ TABLE 3.2 Unified Classification System--Group Symbol&for Grav- elly Soil GW Leas than 5%passing No.2M sieve;C.=D dD,e>>ramer dam at equal to 4;C m(Dyod'/(D,o x D j bdvm 1 and 3 GP Len than 5%passing No.200 sieve;not meting bah criteria for GW GM More than 12%put:sing No.200 sieve;Atterberes limits plot below A-line(Figure 3.3)or plasticity index less than 4 GC More than 12%passing Na 2W sieve;Atterherg's limits plot above A-line(Figure 33);plasticity index greater than 7 GC-GM More than 12%parsing No.200 sieve;Attabergb timit3L fall in hatched area marked CL-ML in Figure 3.3 GW-GM Percent parsing No.200 sieve is 5 to 12;meets the criteria for GW and GM GW-GC Percent passing No.200 sieve is 5 to 12;meets the criteria for GW and GC GP-GM Percent passing No.200 sieve is 5 to 12;mem the c itetia for GP and GM GP.GC Present passing No.200 sieve is 5 to 12;male the criteria for GP and GC SW Less than 5%passing Na 200 sieve:C.=DeO/Dso greater than or equal to 6;C,= x D j between 1 and 3 SP Leas than 5%passing No.200 sieve;not mating both aiteris for SW SM Mae than M-passing Na 200 sieve;Amerbero damns plot below A-Imee(Fa m 3.3)or pLtsticity index less than 4 SC More than 12%parninp No.200 sieve:Atterberg s limits plot above Aline O1Igme M;plasticity index greater than 7 SCSM More than 12%passing Na.2M sieve;Atterberg's limits fall in latched asra carped CL-ML in Figure 3.3 sW-SM Percent passing No.200 sieve is 5 to 12;meets the criteria for SW and SM sW-SC Patent passing No.200 sieve is 5 to 12;meets the criteria for SW and SC SPSM Percent pasting No.200 sieve is 5 to 12;meets the criteria for SP and SM SP1gC Percent passing No.200 sieve is 5 to 12;mom the criteria for SP and SC CL Inorganic:LL<50,Pl>7;plots on or above A-line (tree CL moe in Figure 33) ML Ina rgank;LL<50;M<4 or plots below A-line (ere ML zone in Figure 3.3) OL organic;(LL—ovm-drial)/(1L—not dried)<0.75;LL<50 (sot OL ace in Figure 33) CH inorganic;LL 2 50;Pl plots on or above A-line (sot CH zone in Figure 33) MH htapank;LL a 50;Pf plots below A-iime (ace MH zone in Figure 33) OH organic;pL-oven dried)/(LL—eta dried)<0.75;LL 2 50 (sot OH mote in Figure 3.3) Ci.ML )anemic;plot in the hatdred zone in Figure 33 Pt Peat,[nick amil other dighly organic soils Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 17 FAX(360)277-3187 Engineering Services Associates, Inc. SL*12 PJPG 5L#13 PJPG 5L#21 GJPG 5L#22 GJPG 10126/1906 1012611906 IDfZ6j1906 1012611906 SL*23 PJPG SL#27 PJPG SL#28 GJPG SL 21 P TYPICAL.JPG .f 1012611906 1012611906 10126/1906 1012611906 SL WEST OF ROAD TYPICAL PJPG 5L#WEST OF ROAD G TYPICAL.JPG SL µ 12 G.JPG SL#14 PJPG s' iP -4k 10/2611906 IDj26j1906 10126j1906 1OJ2611906 5L#18 GJPG 5L#18,3PG SL#18-2,JPG 5L#19-G.JPG 1012611906 10126/1906 1012611906 1012611906 5L#19-P.JPG SL#22 PJPG 5L#23 GJPG 5L#25 GJPG 1012611906 1012611906 10/2611906 10126j1906 Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 18 FAX(360)277-3187 AN Engineering Services Associates, Inc. SL#25 P.JPG 5L#26 P.JPG 5L#27 G.JPG SL#28 P.JPG 10126 f 1906 10126 f 1906 1012611906 10 f 2611906 SL#28 P2.JPG 5L#29 G.JPG 5L#29 P.JPG 5L#30 G.JPG 1012611906 10126 f 1906 10126 f 1906 lOf 26 f 1906 5L#30-P.JPG 1012611906 This concludes the soil pit analysis and report. Please contact us at 360-275-7384 if you have any questions. Yours truly, Pat McCullough, PE President, ESA Inc. i Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 19 FAX(360)277-3187