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Home My WebLink AboutGeoTechnical Report - COM Engineering / Geo-Tech Reports - 2/23/2004 Geotechnical Report 23861 NE State Route 3 Parcel #123294100090 Prepared for Marley Young Shelton, Washington by Geotechnical Testing Laboratory Olympia, Washington February 23, 2004 GEOTECHNICAL TESTING LABORATORY MARLEY YOUNG P.O. Box 1343 SHELTON, WA 98584 Re: Geotechnical Report 23861 NE State Route 3 Parcel 123294100090 N47027.146' W122049.538' INTRODUCTION This report summarizes the results of our geotechnical consulting services for the proposed development located at the above-mentioned site in Belfair,Washington. The location of the site is shown relative to the surrounding area on the Vicinity Map, Figure 1. x w Our understanding of the project is based on our discussions with you and our explorations and review of the site. We understand that the site is to be redeveloped with commercial buildings. The site is accessed by a driveway from State Route 3. In general, grading will consist of the excavation of the stormwater ponds,parking facilities, foundations, and footings. The site slopes toward the north and northwest. The steepest slope measured onsite was in excess of 15 percent, located along the western property line. Off the property to the west is an eight-foot retaining wall with minor -groundwater seepage along the base. Therefore,Mason County requires that a geotechnical report be prepared in accordance with the Critical Areas Ordinance. The purpose of our services is to evaluate the surface and subsurface conditions at the site as a basis for providing geotechnical recommendations and design criteria for the project and to satisfy the requirements of the Mason County Critical Areas Ordinance. Geotechnical Testing Laboratory is therefore providing geologic and hydrogeologic services for the project. Specifically,our scope of services for this project will include the following: l. Review the available geologic, hydrogeologic, and geotechnical data for the site area. 2. Conduct a geologic reconnaissance of the site area. 3. Investigate shallow- subsurface conditions at the site by observing the exposed soil and reviewing published well logs. 4. Evaluate the landslide and erosion hazards at the site per the Mason County Critical Areas Ordinance regulations. 10011 Blomberg Street SW, Olympia,WA 98512 1 Phone If: (360)754-4612 Fax#: (360) 754-4848 GEOTECHNICAL TESTING LABORATORY 5. Provide geotechnical recommendations for site grading including site preparation, subgradc preparation,fill placement criteria(including hillside grading),temporary and permanent cut and fill slopes, drainage and erosion control measures. AIU tr I SITE CONDITIONS SURFACE CONDITIONS The proposed building site is located in an area of commercial development in the Puget Sound glacial upland east of the Hood Canal. The site is bordered on the southeast by State Route 3. We conducted a reconnaissance of the site area on February 9, 2004. Building site elevations range from approximately 62 to 77 feet. The building site has vegetation indigenous to the Northwest. The vegetation includes blackberries, Scot's broom, grasses, alder trees, and fir trees. At the time of the site visit,we observed no evidence of surface erosion. No evidence of deep-seated slope instability was observed on the site slopes or areas adjacent to this site at the time of our investigation. Evidence of surface water flow was not observed in the site area at the time of our reconnaissance. The general topography of the site area indicates that drainage flows toward the northwest. Seepage was observed offsite along the base of the western retaining wall. Standing groundwater was observed in three test pits at approximately 2 feet below the ground surface. 10011 Blomberg Street SW, Olympia,WA 98512 2 Phone#: (360)754-4612 Fax#-. (360) 754-4848 I GEOTECHNICAL TESTING LABORATORY SITE GEOLOGY The site is generally situated within the Puget Sound glacial upland- The existing topography,as well as the surficial and shallow subsurface soils in the area, are the result of the most recent Vashon stade(stage)of the Fraser glaciation that occurred between about 10,000 and 12,000 years ago, and weathering and erosion that has occurred since. A description of the surficial soils is included in the `Site Soils"section of this report. In general,the soils on the site are predominantly represented by Vashon glacial till. SITE SO" The Soil Survey ofMason County, USDA Soil Conservation Service (1960)has mapped the site soils as an Everett gravelly sandy loam, 5 to 15 percent slopes(Eh). The Everett soils areY,� a dee somewhat excessively drained pale-brown _ described as very p, gravelly soils. They occur as inextensive gravel ridges on the glacial rq�' moraines, or,more commonly,as fairly continuous outwash t channels between ridges of Alder-wood soils. They have developed upon assorted glacial till and outwash material. Permeability is Y; r rapid(up to 20 inches per hour)with a high rate of water transmission. These soils are typically classified as a"Group A" relative to surficial runoff The soils are further characterized as f � » having medium runoff potential and moderate water erosion " potential. The water capacity for plants is low. Shrink-swell potential is described as low due to the low organic content. The Coastal Zone Atlas, Volume 9,Mason County(MA-11)maps the site as having Vashon Till(Q,,)throughout the site. The till is a tough,dense material of low permeability. It provides excellent foundation support. The site is described as"stable." ty ti SUBSURFACE EXPLORATIONS Subsurface conditions at the site were evaluated by observing the exposed building site soil and reviewing available well logs. Gravelly sandy loam was observed to a depth beyond the scope of the project. 10011 Blomberg Street SW, Olympia,WA 98512 3 Phone#: (360)754-4612 Fax#: (360) 7544848 GEOTECHNICAL TESTLNG LABORATORY. SUBSURFACE CONDITIONS In general,undisturbed dense gravelly sandy loam with areas of occasional fill was observed throughout the site. Groundwater was observed in three test pits at approximately 2 feet below the ground surface. Groundwater seepage was also witnessed along the base of the retaining wall on the adjacent parcel to the west. Based on the site topography and the nature of the near surface soil,seasonally perched groundwater conditions are expected during periods of extended wet weather. } - . .s�. J? .,fir• - Y I ON. fir .t d n_ ;9' pit ;' a x' Vlk r �'t: �`is Seepage Point U , f �► standutg Water i" Seepage Point k �'� .re SLOPE STABILITY Slopes in excess of 15 percent were observed onsite. Since a proposed infiltration pond is proposed within 50 feet of the slope exceeding 15 percent, Mason County requires that a geologic hazards report be completed according to the Critical Areas Ordinance, The Relative Slope Stability of the Southern Hood Canal Area, Washington, (1977)describes the site area as Class I. Class I is expressed as, Areas believed to be stable. Slopes generally less than IS percent, but may be greater locally in areas too small to be shown at the map scale. Largely comprises rolling uplands underlain by very stable material such as young glacial till, mantled in places by a thin layer of sandy gravel or other permeable material; also includes flood plains, deltas, alluvial fans, and some beach deposits. Class 1 areas immediately adjacent to steep slopes of class 3 areas may be threatened by potential landsliding. Normal,proper engineering practices generally are adequate to insure stability in these areas. The near-surface gravelly sandy loam soils are in a dense to very dense condition except at the ground surface. The surficial soils are generally in a medium dense condition. In general,the undisturbed native soils of the site consist of a mixture of variable amounts of gravel,sand, and silt. These soil materials are in a dense condition except where they have been disturbed by weathering activity. These soils are generally stable relative to deep-seated failure. No evidence of deep-seated landslide activity was observed at the site at the time of our investigation. Weathering and erosion are natural processes that can affect steep slope areas. Instability of this nature is typically confined to the upper weathered or disturbed zone,which has been disturbed and has a lower strength. Evidence of minor surficial erosion, raveling and sloughing was not observed on the sloping areas during our investigative visit. 10011 Blomberg Street SW, Olympia,WA 98512 4 Phone#: (360) 754-4612 Fax#: (360) 754-4848 GEOTECHNICAL TESTING LABUKA 11 Ulm Y Significant weathering typically occurs in the upper 2 to 3 feet and is the result of o. dation root penetration, wet/dry cycles, and freeze/thaw cycles. Erosion in steep slope areas such as this can be reduced by encouraging vegetation and discouraging runoff from the steep slope. Erosion control recommendations for the sloping areas are provided in the``Erosion Control"section of this report. CONCLUSIONS AND RECOMMENDATIONS GENERAL Based on the results of our site reconnaissance and subsurface observations, and our experience in the area, it is our opinion that the site is suitable for the proposed commercial structure and stormwater pond. The slope is stable relative to deep-seated instability and will not be affected by the proposed commercial structure and stormwater pond. Proper drainage control measures will reduce or eliminate the potential for erosion and improve slope stability. Deep-seated instability is not expected to affect the commercial structure and stormwater pond. In general,the site soils are not suitable for use as structural fill material. Since saturated soil conditions may be associated with these soils during or following extended periods of rainfall; we recommend that earthwork be undertaken during favorable weather conditions to reduce grading time and construction costs. If our analysis and recommendations are followed, we do not anticipate any on site or off site impact from the proposed construction. It is our conclusion that potential landslide hazards can be overcome so as not to cause harm to property, public health and safety, or the environment. Pertinent conclusions and geotechnical recommendations regarding the design and construction of the commercial structure and stormwater pond are presented below. J .tZz � i � 1 �,'�A J'r 3' .� d' ;,]R;•.Ytdrr ...x...'r - ':�'-�`�-y .r.„'i+� ' �`F`r �<_- «.--+�"' ^ _ �• z , s LANDSLIDE—EROSION HAZARD AREAS Classification The Mason County Critical Areas Ordinance(17.01.100)defines a landslide hazard area as one containing slopes equal to or greater than 15 percent with springs or groundwater seepage. Site slopes exceed 15 percent and groundwater seepage is apparent along the base of the neighboring retaining wall. Based on this,this site does meet the technical criteria of a landslide hazard. 10011 Blomberg Street SW, Olympia,WA 98512 5 Phone#: (360) 754-4612 Fax#: (360) 754-4848 GEOTECHNICAL TESTING LABORATORY The Mason County Critical Areas Ordinance(17.01.104)defines an erosion hazard area as: Areas in Mason County underlain by soils which are subject to severe erosion when disturbed. Such soils include, but are not limited to, those for which potential for erosion is identified in the Soil Survey of Mason County, USDA Soil Conservation Service, 1960,. or any subsequent revisions or additions to this source. These soils include, but are not limited to, any occurrence of River Wash ("Ra') or Coastal Beaches ("Cg') and the following when they occur on slopes 15%or steeper. a. Alderwood gravelly sandy loam ("Ac"and"Ad') b. Cloquallum silt loam ("Cd') c. Harstine grmmelly sandy loam ("Hb') d. Kitsap silt loam ("Kc') The soils at the site are mapped as Everett gravelly loamy sand(Eh). This site does not meet the technical criteria of an erosion hazard area. Slope Stability Based on our field observations, explorations, and our experience ,vith the soil types encountered on the property, Nve conclude that although portions of the neighboring slopes exceed 100 percent,they are generally stable relative to deep-seated failure in their present configuration. A building setback from landslide hazard areas is required unless evaluated and reduced by an engineering geologist or a licensed professional engineer. Based on our geotechnical evaluation of the site and our experience in the area, a building setback will be needed for this lot. We recommend a setback distance for the retention pond of 15 feet from the top of the western slope. The setback may be measured from the bottom of the pond to the face of the slope. The following figure represents a shear angle for the site soils. Shear angle and cohesion are variables used to model the site. Peak Shear Stress vs. Normal Stress Gravelly Sandy Loam 3000 2500 i C N i 2000 H U 1500 01 co R 1000 a soo — -1/4 ton 1--w-1/2 ton —.:--1 ton o - 0 500 1000 1500 2000 2500 3000 Normal Stress (pst) 10011 Blomberg Street SW, Olympia,WA 98512 6 Phone#: (360)7544612 Fax#: (360) 754-4848 GEOTECHNICAL TESTING LABORATORY Slope stability was modeled using the GEO-SLOPE/W program(version 5.13) in both static and dynamic conditions Reid Realty Slope A (ca=0.3). Factors of safety were determined using Bishop's, Analysis Method: Morgenstern-Price Janbu,and the Morgenstern-Price methods. Three cross- Direction of Slip Movement:Left to Right sections were modeled for the site. The site geology was Seismic Coefficient:Horizontal and vertical modeled using a retaining wall and a monolithic laver of _ gravelly sandy loam. The soil was determined to have a unit -,eight of 128 pc£ cohesion of 500 psf, and a shear angle of 39°. Conservative soil values were used in the model,unit weight of 128 pcf, cohesion of 250 psf, and a shear angle(�) r of 20°. Under static conditions, the slopes remained stable to ' . deep-seated and shallow failure. Under dynamic loading,the ! 2816 computations demonstrated that the slope is not susceptible to surficial raveling; large deep-seated failure was a6 not demonstrated by our model. The following figures 78 i illustrate a moment F.S. over 1.00 under dynamic conditions. 74 tit' The following solutions are the lowest factors of safety o 66 generated by the models for the three cross-scetions. > 62 Every 58 — Soil Model: ! w 54 Unit Weight:128 Cohesion:250 Reid Realty 5D I Plik -pi 1111 I Slope B 6-5 0 5 10 15 20 25 30 35 40 45 50 55 60 65 7o 75 Analysis Method: Morgenstern-Price Distance(ft) Direction of Slip Movement: Left to Right Seismic Coefficient: Horizontal and Vertical Reid Realty f i!'! l i + Slope C (_i;. Analysis Method: Morgenstern-Price Direction of Slip Movement: Left to Right Seismic Coefficient: Horizontal and Vertical 92 1 84 C 80 _ 3, 74 76 i 7D > - : ,,,, W o 62 64 e, 5g Soil Model:Mohr-courom �— ur,wr� y1 Unit Weight:128 60 — SM�, , LL1 Cohesion:250 56 I I F za _ �� I Phi:2Q I I I I I I iJ -5 0 5 10 15 20 25 30 35 40 45 '� 4 5 7 0 v 10 10 20 Z, 30 35� D 45 50 57 GO C� D 75 00 Distance(ft) Distance(ft) Slope C is modeled using a retaining wall, shown as a blue wedge. For all three profiles,the groundwater table is represented by the dashed blue line. Changes in slope stability are not expected to result from minor excavations in the development of the site. Grading in the building portion of the site should be conducted in accordance with geotechnical recommendations provided herein. 10011 Blomberg Street SW, Olympia,WA 98512 7 Phone#: (360) 754-4612 Fax#: (360) 7544848 III GEOTECHNICAL TESTING LABORATORY As previously discussed,weathering,erosion,and the resultant surficial sloughing and landsliding are natural processes that affect slope areas. Significant weathering typically occurs in the upper 2 to 3 feet and is the result of oxidation, root penetration,wet/dry cycles and freeze/thaw cycles. No significant surficial raveling or sloughing was observed in the natural (undisturbed)sloping portions of the site. To manage and reduce the potential for these natural processes,we recommend the following: 1. No drainage of concentrated surface water or significant sheet flow onto the slope area. 2. No filling within the setback zone unless retained by retaining walls or constructed as an engineered fill. SEISMIC—LIQUEFACTION HAZARD According to the Seismic Zone Map of the United States contained in Figure 16-2 of the 1997 UBC(Uniform Building Code),the project site is located within Seismic Risk Zone 3. Based on the subsurface conditions observed at the site,we interpret the site conditions to correspond to a seismic Soil Profile Type SD, for Stiff Soil,as defined by Table 16-J (UBC). This is based on the range of SPT(Standard Penetration Test)blow counts and/or probing with a '/-inch diameter steel probe rod. The shallow soil conditions were assumed to be representative of the site conditions beyond the depths explored. Based on our review of the subsurface conditions,we conclude that the site soils have a low susceptibility to liquefaction. The near-surface soils are generally in a dense condition and the static water table is located near the ground surface. Shaking of the already dense soil may produce a denser configuration and subsequently excess pore water pressures are not expected to be produced. EROSION CONTROL It is our opinion that the potential erosion hazard of the site is not a limiting factor for the proposed commercial structure and stormwater pond. Removal of natural vegetation on the slopes should be minimized and limited to the active construction areas. Landscaping around the proposed building location is permissible,but understory growth on the slopes should be encouraged as much as possible as a deterrent to erosion. Temporary and permanent erosion control measures should be implemented and maintained during construction and/or as soon as practical thereafter to limit the additional influx of water to exposed areas and protect potential receiving waters. Erosion control measures should include,but not be limited to, silt fences,berms and swales with ground cover/protection in exposed areas. Any re-contouring of the site will create a need for erosion control measures as listed above. Erosion control plans shall be provided by the project engineer. EARTHWORK Site Preparation All areas to be excavated should be cleared of deleterious matter including debris, and vegetation. Based on our explorations,we estimate that most clearing has already been performed. 10011 Blomberg Street SW, Olympia,WA 98512 8 Phone#: (360) 754-4612 Fax#: (360)754-4848 GEOTECHNICAL TESTING LABORATORY Where placement of fill material is required,the exposed subgrade areas should be cleared of deleterious material to a firm and unyielding surface prior to placement of any fill. Any soft;loose or otherwise unsuitable areas delineated during construction or probing should be compacted, if practical,or over-excavated and replaced with structural fill, based on the recommendations of our site representative. Fill The fill for berms placed above the ground surface(if designed)should be placed in horizontal lifts of appropriate thickness to allow adequate and uniform compaction of each lift. Fill should be compacted to at least 90 percent of MDD (maximum dry density as determined in accordance with ASTM D-1557)to within 2 feet of subgrade and 95 percent MDD in the upper 2 feet. The appropriate lift thickness will depend on the fill characteristics and compaction equipment used. We recommend that the appropriate lift thickness be evaluated by our field representative during construction. The suitability of material for use as fill will depend on the gradation,moisture content and permeability coefficient, required by the design engineer,of the soil. As the amount of fines (material passing No. 200 sieve)increases, soil becomes increasingly sensitive to small changes in moisture content and adequate compaction becomes more difficult to achieve. Material placed for fill should be free of debris,organic matter,trash and cobbles greater than 6 inches in diameter. The moisture content of the fill material should be adjusted as necessary for proper compaction. Suitability of On-Site Soils as Fill On-site soils may be considered for use as fill. In general,the native soils (loamy sand)encountered on the site should have more than 10 percent fines(material passing the US No. 200 Sieve). Site Drainage Surface water runoff should be controlled by a system of curbs;berms, drainage swales,and/or catch basins and prevented from flowing on the steep slope or the fill slopes. Site drainage plans shall be provided by the project engineer. LIMITATIONS We have prepared this report for the use of Marley Young and members of his design team,to use in the design of a portion of this project. The data used in preparing this report, and this report, should be provided to prospective contractors for their bidding or estimating purposes only. Our report, conclusions and interpretations are based on data from others and our site reconnaissance,and should not be construed as a warranty of the subsurface conditions. Sufficient consultation with our firm during construction should continue, to confirm that the conditions encountered are consistent with those indicated by our observations,to provide recommendations for design changes should the 10011 Blomberg Street SW, Olympia,WA 98512 9 Phone 4: (360) 754-4612 Fax#: (360) 754-4848 GEOTECHNICAL TESTING LABORATORY conditions revealed during the work differ from those anticipated, and to evaluate whether earthwork and foundation installation activities comply with our specifications. The scope of our services does not include services related to environmental remediation and construction safety precautions. Our recommendations are not intended to direct the contractor's methods,techniques,sequences or procedures,except as specifically described in our report for consideration in design. If there are any changes in the loads,grades,locations,configurations or types of facilities to be constructed,the conclusions and recommendations presented in this report may not be fully applicable. If such changes are made, we should be given the opportunity to review our recommendations and provide written modifications or verifications,as appropriate. Respectfully, GEOTECHNICAL TESTING LABORATORY i �•o Wa* ►Gf� pa4-11 I -�6fj � Harold Parks, L.G.,L.E.G. �r �+ Oo.abow C'� Senior Engineering Geologist c 827 A d Go I 10011 Blomberg Street SW, Olympia,WA 98512 10 Phone#: (360) 7544612 Fax#: (360) 754-4848 G 1�14:OTECH IICAL TESTING LAG T ORY :77-7; f1�• ' 'ti'Czr¢val .it r 9A X2 }-'+' .�� ! x it j +' :4's;• • � • f• l E t r t; - J Figure 1 f 10011 Blomberg Street SW, Olympia, WA 98512 Phone#: (360) 754-4612 Fax 4:(360) 754-4848 • • ~•••�;, f � �.•.•.r�-i` I-M lime • oil; mom 'CY 1. ♦c G�4' 1�� '� �LTrw„COMMON: Will • � '<'i� 7` { 1 1 3. �• 'i� tit'{ 1 } r"'i >y. 'x.L • • �„ r � ?'�h't'.ta.sr,.,�XJ��44-��:�7.t��tt,,��'!.��y�y,��{��.t�,.�.��f;Y;1h,."-��" Ft�1y� .�,�+7 .�� _. •� • �r S Geotechnical S 88"18, W 357.2 (REC) Testing H2O S 87-15'14" E 364.52 (CAU H2o Laboratory "MOO WjM"M_ AIM x 0 M AS= Geotechnical Services .41 Ail: QA/QC Services Testing Services A AM 04 I aig;. .4 'M 10011 Blomberg St.SW o, to Olympia,WA 98512 4 Phone:(360)754-4612 Fax:(360)7544 - 848 4. ub. Date: 02115t2004 Designed by: MLY A A .. Drawn by: MLY Checked by: LL Dwg#:02-15-04-010 or .114, 00 ;!S R 04 'A PROJECT NAME: FIRST FLOOR REID REALTY SITE ,%A L E -EV. 69.53' 23861 NE STATE ROUTE 3 A, . . PARCEL 123294100090 Ar & A, rl SCALE:1 Inch=20 feet A, op N�tN FIGURE 2 Alan Cady,et al—Relfair Site Redevelopment-Revised SUPPORTING CALCULATIONS Marley L.Young,Consulting Engineer Project No.2003-19 POND DESIGN The computer program, WaterWorks, uses rectangular trapezoidal basins for the retention/detention facilities analysis. When designing a basin, other than rectangular,the WaterWorks trapezoidal basin must be modified by length, width,and side slopes in order to closely mirror the infiltration, and peak elevation of the basin as designed. SEDIMENT POND Designed as PART OF A CRESCENT FLOOR AREA = 880.00 sf 3:1 Side Slopes 2.5' above floor area =2187.48 sf Volume =3712.11 cf WaterWorks FLOOR AREA = 880.00 sf W= 17.19 & L = 51.18 Side Slopes 1,2&4 = 3.1 Side Slope 3 = 4:1 Volume at 2.5' above floor =3753.9 cf Volume at 2.48' above floor =3709.8 cf Year Peak Vol WW Area 1 Area Vol/Crescent 10 1.97 2666.39 880 1874.18 2651.90 INFILTRATION POND Designed as a CRESCENT FLOOR AREA = 1114.20 sf 3:1 Side Slopes 2.5' above floor area =3008.47 sf Volume =4961.27 cf WaterWorks FLOOR AREA = 1114.20 sf W= 15.368 & L = 72.50 Side Slopes t & 3 =4:1 Side Slopes 2 &4 =3:1 Volume at 2.5' above floor =4962.8 cf Year Peak Vol WW Area I Area 2 Vol/Crescent '/2 0.26 307.77 1114.20 1233.69 305.09 2 0.80 1097.85 1114.20 1631.00 1091.53 10 1.40 2201.45 1114.20 2095.21 2210.75 100 2.32 4444.93 1114.20 2853.52 4447.29 1/12/04 12 :11:7 am Marley Young Engineer page 1 CADY PROFESSIONAL MALL STORMWATER CONTROL TOTAL INFILTRATION PROD 2003-19 2003-19x.pgm --------------- ------- BASIN SUMMARY BASIN ID: A NAME: 1/2 yr storm EXISTING SBUH METHODOLOGY TOTAL AREA. . . . . . . : 1.24 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : TYPEIA PERV IMP PRECIPITATION. . . . : 2.24 inches AREA. . : 1.01 Acres 0 .23 Acres TIME INTERVAL. . . . : 5.00 min CN. . . . : 85.00 98 .00 TC- - - - : 5. 00 min 5.00 min ABSTRACTION COEFF: 0.20 TcReach - Shallow L: 110.00 ks:27.00 s:0.0400 PEAR RATE: 0.31 cfs VOL: 0.12 Ac-ft TIME: 480 min BASIN ID: B NAME: 2 yr storm EXISTING SBUH METHODOLOGY TOTAL AREA. . . . . . . : 1.24 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : TYPEIA PERV IMP PRECIPITATION. . . . : 3 .50 inches AREA. . : 1.01 Acres 0.23 Acres TIME INTERVAL. . . . .. 5.00 min CN. . . . : 85.00 98 . 00 TC. . . . . 5 . 00 min 5 . 00 min ABSTRACTION COEFF: 0.20 TcReach - Shallow L: 200.00 ks:13 . 00 s:0.0200 PEAK RATE: 0.63 cfs VOL: 0.23 Ac-ft TIME: 480 min BASIN ID: C NAME: 10 yr storm EXISTING SBUH METHODOLOGY TOTAL AREA. . . . . . . : 1.24 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : TYPEIA PERV IMP PRECIPITATION. . . . : 4.75 inches AREA. . : 1.01 Acres 0.23 Acres TIME INTERVAL_ . _ . : 5.00 min CN. . . . : 85.00 98 .00 TC. . . . . 5.00 min 5.00 min ABSTRACTION COEFF: 0.20 TcReach - Shallow L: 110. 00 ks:27.00 s: 0.0400 PEAK RATE: 0 .97 cfs VOL: 0 .35 Ac-ft TIME: 480 min 1/12/04 12 :11:7 am Marley Young Engineer page 2 CADY PROFESSIONAL MALL STORMWATER CONTROL TOTAL INFILTRATION PROD 2003-19 2003-19x-pgm ------------------------ ----BASIN SUMMARY BASIN ID: D NAME: 100 yr storm EXISTING SBUH METHODOLOGY TOTAL AREA. . . . . . . : 1.24 Acres BASEFLOWS: 0-00 cfs RAINFALL TYPE_ - - - : TYPEIA PERV IMP PRECIPITATION. . . . : 6.75 inches AREA. . : 1-01 Acres 0 .23 Acres TIME INTERVAL. . . . : 5.00 min CN. . . . : 85. 00 98. 00 TC. . . . . 5. 00 min 5. 00 min ABSTRACTION COEFF: 0.20 TcReach - Shallow L: 110.00 ks:27.00 s:0.0400 PEAK RATE: 1.52 cfs VOL: 0 .55 Ac-ft TIME: 480 min BASIN ID: LC NAME: 10 year storm EXISTING SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0.66 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : TYPEIA PERV IMP PRECIPITATION. . . . : 4.75 inches AREA. _ : 0.50 Acres 0-16 Acres TIME INTERVAL. . . . : 5.00 min CN. . . . : 85-00 98 .00 TC. . . . . 5. 00 min 5. 00 min ABSTRACTION COEFF: 0-20 TcReach - Shallow L: 110.00 ks:27.00 s:0.0400 PEAK RATE: 0.52 cfs VOL: 0-19 Ac-ft TIME: 480 min BASIN ID: a NAME: 1/2 year storm developed SBUH METHODOLOGY TOTAL AREA. . . . . . . : 1.24 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE- - - - : TYPEIA PERV IMP PRECIPITATION_ _ _ . : 2.24 inches AREA. - : 0.69 Acres 0 .55 Acres TIME INTERVAL. . _ . : 5.00 min CN. . . . : 85-00 98.00 TC. . . . _ S-00 min 5.00 min ABSTRACTION COEFF: 0.20 TcReach - Shallow L: 110. 00 ks:27.00 s:0.0400 PEAK RATE: 0.39 cfs VOL: 0-15 Ac-ft TIME: 480 min 1/12/04 12 :11:7 am Marley Young Engineer page 3 CADY PROFESSIONAL MALL STORMWATER CONTROL TOTAL INFILTRATION PROJ 2003-19 2003-19x.pgm ----------------------------BASIN SUMMARY BASIN ID: b NAME: 2 year storm developed SBUH METHODOLOGY TOTAL AREA. . . . . . . : 1.24 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : TYPEIA PERV IMP PRECIPITATION. . . . : 3 .50 inches AREA. _ : 0.69 Acres 0.55 Acres TIME INTERVAL. . . . : 5.00 min CN. . . . : 85.00 98 .00 TC. . _ . _ 5.00 min 5. 00 min ABSTRACTION COEFF: 0 .20 TcReach - Shallow L: 110.00 ks:27 . 00 s:0.0400 PEAK RATE: 0.72 cfs VOL: 0.27 AC-ft TIME: 480 min BASIN ID: c NAME: 10 year storm developed SBUH METHODOLOGY TOTAL AREA. . . . . . . : 1.24 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. . . . : TYPEIA PERV IMP PRECIPITATION. . _ . : 4.75 inches AREA. . : 0.69 Acres 0.55 Acres TIME INTERVAL. . . . : 5.00 min CN. . . . : 85.00 98. 00 TC. . . . . 5.00 min 5. 00 min ABSTRACTION COEFF: 0.20 TcReach - Shallow L: 110 .00 ks:27. 00 s:0.0400 PEAK RATE: 1.05 cfs VOL: 0.39 Ac-ft TIME: 480 min BASIN ID: d NAME: 100 year storm developed SBUH METHODOLOGY TOTAL AREA. . . . . . . : 1.24 Acres BASEFLOWS: 0. 00 cfs RAINFALL TYPE. . . . : TYPEIA PERV IMP PRECIPITATION. . . . : 6.75 inches AREA_ . : 0.69 Acres 0.55 Acres TIME INTERVAL. . . . : 5.00 min CN. . . . : 85.00 98.00 TC. . . . . 5. 00 min 5. 00 min ABSTRACTION COEFF: 0 .20 TcReach - Shallow L: 110. 00 ks:27. 00 s: 0.0400 PEAK RATE: 1.60 cfs VOL: 0.59 Ac-ft TIME: 480 min 1/22/04 12 :11:7 ant Marley Young Engineer page 4 CADY PROFESSIONAL MALL STORMWATER CONTROL TOTAL INFILTRATION -- PROD 2003-19 --------BASIN SUMMARY BASIN ID- dbuild NAME: 100 year storm off of building SBUH METHODOLOGY TOTAL AREA. . . . . . . : 0-10 Acres gp,SEFLOWS: PERV00 cfs IMP RAINFALL TYPE- - - - : TYPEIA 0.00 Acres 0.10 Acres PRECIPITATION- - - - : 6-75 inches • - - 0. 00 98 .00 TIME INTERVAL. - - - - 5.00 min TC- -TC. . - - 0.00 min 5 .00 min - ABSTRACTION COEFF: 0-20 TcReach - Shallow L: 110.00 ks:27. 00 s:0.0400 480 min PEAK RATE: 0.14 cfs VOL: 0 . 05 Ac-ft TIME: Ma.rle young Engineer page 5 1/32/04 12 :11:7 am �Y PROFESSIONAL MALL STORMWATER CONTROL TOTAL INFILTRATION PROD 2003-19 STAGE STORAGE TABLE TRAPEZOIDAL BASIN ID No. ST Description: SEDIMENT FOND DURING CONSTRUCT Length- 51.18 ft_ Width: 17.19 ft. Side Slope 1.: 3 Side Slope 3: 4 Side Slope 2 : 3 Side Slope 4: 3 Infiltration Rate: 7 .50 min/inch STAGE c----STORlw'5----> s <----s1�oa�s----> STAGE <----SWIUV B----> sires <----smxaGs----> (ft) ---cf--- --Ac-Pt- (ft) 100.00 0_0000 0.0000 100.65 665.99 0.0153 101.30 1536 0.0353 101-95 2632 0.0604 100.05 44.525 0.0010 100.70 725.37 0.0167 101.35 1612 0_0370 102.00 2726 0.0626 100.10 90.129 0.0021 100_75 785.95 0.0180 101.40 1689 0.0380 102.OS 2822 0.0648 100.15 136_82 0_0031 100.80 847.77 0_0195 101_45 1769 0.0406 102.10 3019 0.0670 100_20 184.62 0.0042 100.85 910.82 0.0209 101.50 1848 0.0424 102.15 93 100.25 233.52 0.0054 100.90 975.11 0.0224 101.55 1929 0.0443 102.20 3119 0.0716 100.95 1041 0.0239 101.60 2012 0.0462 102.25 3221 0.0739 100.30 283.55 0_0065 0.0481 102.3D 3324 0.0763 100.35 334.70 0.0077 101.00 1107 0.0254 101.65 2096 100.40 397.00 O.OD89 101.05 1176 0.0270 101.70 2192 0.0501 102_35 3429 0.0787 100.45 440.45 0-0101 101.10 1245 0.0286 101.75 2269 O.OS21 102.40 3536 0.0512 100.50 495.07 0.0114 101.15 1316 0.0302 101.80 2356 0.0541 102.45 3644 0.0837 190.55 55D.86 0.0126 101-20 1388 0.0319 101.85 2448 0.0562 102.50 3754 0.0862 101.90 2539 0.0583 100_60 607_83 0.0140 101.25 1461 0.0335 1/12/04 12 .11:7 am Marley Young Engineer page 6 CADY PROFESSIONAL MALL STORMWATER CONTROL TOTAL INFO TRAT10Ng� PROD 2003-19 ------- STAGE STORAGE TABLE Infiltration Rating Curve for Storage Struct ST *+�rmrramlp�7_> STAGS <-nairrrrranrr@7-> STAGS <-TuarLTRA 0y, STAGS <-INFIL13tAl1CN-> ST&GE ---cfs-- (£t) ---cfs-- ------- ---efs-- - (ft) ---efe-' ------- (ft) -'-'--- (ft) "-- 1Q1.30 0.2848 101.95 0.3560 IGO.00 O_1629 100.65 0.2204 200.05 0_1671 100_70 O_2251 101_35 0.2900 102.00 0.3618 100.75 0.2299 101.40 0.2953 102-05 0.3676 100.10 0.1713 102_10 D.3734 100.80 0.2346 101.45 0.3606 100.25 0.2756 102_15 0.3793 200.85 0.2395 101.50 0.3060 I00.20 0.1799 1p2_2Q 0.3852 100.90 0.2443 101.55 0.3114 1D0.25 0.1842 102.25 0.3922 100.95 0.2493 101.60 0.3166 100_30 Q.1886 101.00 0-2542 101.65 0.3223 102.30 0.3972 100.35 0.1930 102.35 0_4033 101.05 0.2592 101.70 0.3278 100.40 0.1975 202_40 0.4094 100.45 0.2020 201.10 0.2642 101.75 0_3334 101_15 O_2693 101.80 0.3390 102.45 0.4155 100.50 0.2065 102.50 0.4217 100.55 0.2112 101.20 0.2744 101.65 0.3446 100.60 0.2157 101_25 0.2796 101.90 0.3503 2 :11:7 am Marley Young Engineer page 7 1 12 04 1 . LADY PROFESSI ONAL MALL STORMWATER CONTROL TOTAL INFILTRATION PROD 2003-19 2003-19x.pgm STAGE STORAGE TABLE TRAPEZOIDAL BASIN ID No. Tb Description: Length: 72 .50 ft. Width: 15.37 ft_ Side Slope 1: 4 Side Slope 3: 4 Side Slope 2: 3 Side Slope 4: 3 Infiltration Rate: 7.50 min/inch STAGE <----STORAGE----> STAGE <----STORAGE----> STAGE <----STORAGE.{----> STAGE <----STORAGE----> (ft) ---cf--- --AC-Ft- (ft) ---cf--- --Ac-Ft- 100_00 0.00000-0000 -100.65 856.64 0.0197 101.30 2004 0-0460 101.95 3463 0.0795 100.05 56.480 0.0013 100.70 936.22 0.0215 101_35 2105 0_0483 102.00 3589 0.0824 100.10 114.51 0_0026 100.75 1016 0.0233 101.40 2207 0.0507 102.05 3717 0.0853 100.15 174_10 0.0040 100_80 1097 0.0252 101.45 2312 0.0531 102.10 3847 0.0883 100.20 235.27 0.0054 100.85 1179 0.0271 101.50 2418 0.0555 102.15 3979 0_0914 100.25 298.02 0.0068 100.90 1264 0.0290 101.55 2527 0.0580 102.20 4114 0.0944 100_30 362.37 0.0083 100.95 13SO 0.0310 101-60 2637 0.0605 102.25 4250 0.0976 100.35 428_34 0_0098 101.00 1438 0.0330 101-65 2749 0_0631 102_30 4388 0.1007 100.40 495.92 0.0114 101.05 1528 0.0351 101.70 2863 0.0657 102.35 4529 0.1040 100.45 565.15 0.0130 101.10 1619 0.0372 101.75 2979 0.0684 102.40 4671 0.1072 100.50 636.02 0.0146 101.15 1713 0.0393 101.80 3097 0.0711 102.45 4816 0.1106 100_55 708.55 0_0163 101.20 1808 0.0415 101.85 3217 0.0739 102.50 4963 0.1139 100.60 782.75 0_0180 101.25 1905 0.0437 101_90 3339 0.0767 1/12/04 12 :11:7 am Marley Young Engineer page 8 CADY PROFESSIONAL MALL STORMWATER CONTROL TOTAL INFILTRATION PROD 2003-19 2003-19x.pgm - -STAGE STORAGE TABLE Infiltration Rating Curve for Storage Struct Tb STAGE <-1NFILMRAT10N-a STAGE <-33U rr43U=0K-> STAIGS <-jNFIL7RAT10(N-> STAGE <-1N=TUAT10ff > -- ------- (ft) ---cfs-- --- (ft) ---cfs-- ------- (£t) ---efs-- ------- 100.00c 0.2063 a 100.65- 0.2874 101.30 0.3764 101.95 0.4734 100.05 0.2123 100.70 0.2939 101.35 0.3836 102.00 0.4812 100.10 0.2183 100.75 0.3006 102.40 0.3900 102.05 0.4890 100.15 0.2243 100.80 0.3072 101.45 0.3981 102.10 0.4969 100.20 0.2304 100.85 0.3139 101.50 0.4054 102.15 0.5049 100.25 0.2366 100.90 0.3207 101.55 0.4128 102.20 0.5128 100.30 0.2427 100.95 0.3275 101.60 0.4202 102.25 0.5209 100.35 0.2490 101.00 0.3343 102.65 0.4276 102.30 0.5289 100.40 0.2553 101.05 0.3412 101.70 0.4352 102.35 0.5371 100.45 0.2616 101.10 0.3482 101.75 0_4427 102.40 0.5452 100.50 0.2680 101.15 0.3552 101.80 0.4503 102.45 0.5535 100.55 0.2744 101.20 0.3622 101.85 0.4580 102_50 0.5617 100.60 0.2809 101.25 0.3693 101.90 0.4657 1/12/04 12:11: 7 am Marley Young Engineer page 9 =Y PROFESSIONAL MALL STORMWATER CONTROL TOTAL INFILTRATION PROD 2003-19 2003-19x.pgm ------ STAGE DISCHARGE TABLE OVERFLOW WEIR ID NO. W Description: Ratio (h:lv) : 3 .2100 Weir length: 4.0000 ft. El : 103 . 00 ft. Weir Increm: 0-05 STAGE <--DISCH886E---> STA63's <--DISC---> STAGR <--DISCMRGS---> STAGB <--DISCEMNZB---> (ft) cfs-- (ft) cfs-- (ft) ---Cfs-- ------- (ft) ---cfs-- ------- 103.00 0.0000 103.30 2.5267 103.60 8.2960 103.90 17.3S2 103.05 0.1489 103.35 3.2694 103.6S 9.5703 103.95 19_200 103.10 0.4341 103.40 4.0987 103.70 10.937 104.00 21.147 103.15 O_8215 103.45 5.0151 103.75 12.397 103.20 1.3016 103.50 6.0195 103.80 13.952 103.25 1.8706 103.55 7.1126 103.85 15.603 I/12/04 12 :11:7 am Marley Young Engineer page 10 CADY PROFESSIONAL MALL STORMWATER CONTROL TOTAL INFILTRATION PROD 2003-19 2003_19x_P9T -_=-___________________________ HISTORY OF HYDROGRAPH ACTIVITY Datc of Session. 1/12/04 12:10.11 am EARR S MoVS A to 1 8_OD late 0.3126 cfs 0.1209 ac-£t MOVE $ to 2 g.00 hrs 0.6326 cfs 0.2327 ac-ft N10VB C to 3 D_9693 cfs 0.3521 ac-ft 8.00 bra MOVE D to 4 g.00 brs 1.5186 cfs 0.5474 ac-ft MC)VE a to 5 0.3937 cfs 0.1486 ac-£t 8.00 hra MOVE b to 6 0.7191 efa 6.2660 ac-ft S.DD brs MOVE c to 7 1.0543 cfs 0.3878 ac-ft $.DD bra MOVE d to e i_5971 cfs 0.5874 ae-ft 8.00 bra LPOOL 1 e1/2n 1 5 Th W 9 Outo hyd volume O.29 9 mat PaakQ Sto Dis PkStg Description 307.77 of 0.31 D.39 Tb W 1D0.26 1/2 LpOOL 2 12^ 2 6 Tb 47 10 �tQ hyd volume MatchQ peakQ Sto Dis P1cStg Description W yD0.80 0.31 10 1097.85 of 0_63 0_72 Th LpOOL 3 -10" 3 7 Tb W 11 Pkst outo hyd volamc Matcho Pe�lc4 Sto Dis g of ' tioa 11 2207.45 Description, 101.40 0.39 0-97 1-D5 Th W 10 LP00L 4 ^100^ 4 8 Th W 12 PkStg 0utQ hYd Volume Matcbo Pe3302 Sto Dis Description4444.93 of 1.52 1-60 Th W 102.32 0.53 12 10D SPL1T W 1 13 17 D-0o hre 0.0000 cfs O.00DO ac-£t 0.2375 cfs 0-1486 ac-ft 8-25 hra SPLIT W 2 14 18 MARLEY L. YOUNG, CONSULTING ENGINEER - .O. BOX 1343, SHELTON, WA 98584-0959 ngi nee Eri ng (360)426-7475-(360)490-0939-Fax(360)426-5789 Stormnrater Site Plans Marley L. Young, P.E., P.L.S. ' Sewer Extensions f Civil Engineer& Land Surveyor ,liil!illl ��I CADY ET AL Reed Realty Building- Belfair 2/9/04 Quattro Pro EMERGENCY OVERFLOW WEIR 2003-19.wb1 CALCULATION OF THE WATER DEPTH OVER THE OVERFLOW WEIR tab A DOE Manual Fig 111-4.3 Q100=3.21(LHA312+2.4HA512) Trial Method If Q100= 1.6 If L= 6 and H= 0.182 <0.2 O.K. 0.465863 0.033915 then Q100= 1.604287 Q100 ACTURAL 1.6 O.K. Calculate Velocity V=Q/A * Doe Manual pg 1-6-21 AREA= LH +3*HA2 L= 6 H= 0.182 AREA= 1.191372 then V= 1.346588 fps< 1.5fps O.K. DISCHARGE OF EMERGENCY OVERFLOW SPILLWAY DOES NOT REACH EROSION VELOCITY TA Pa.le#1 of 1 GEOTECHNICAL TESTING LABORATORY MARLEY YOUNG P.O. Box 1343 SHELTON, WA Re: Reid Realty Sample from Peninsula S&G Gentlemen: Constant Head Permeability testing was performed on Samples 1 and 2 of material picked up Jan. 7,2004 from Peninsula Sand&Gravel. The results are as follows: Sample#1: 3.0 x 10-3 = 14.1 min/in Sample#2: 7.2 x 10-3=5.88 min/in If you have any questions concerning the test results,the procedures used,or if we can be of any further assistance please call on us at (360)7544612. Respectfully Submitted, GEOTECH ICAL TESTING LABORATORY Harold Parks Engineering Geologist 100I 1 Blomberg Street SW,Olympia,WA 98512 FROM : GEOTESTLAH PHONE NO. : 360I544li4d Jan. ee eUU'4 Je-ton•, �l GEOTECEMCAL TESTING LAB Dek- 1 IM/2003 F11,E a Reid RwAy Bmiu F 1,oy#: 3 Ment MArky young Dmbq Ty pm HMow Stem Augv Dtftd: 1 R6 inrDee Dcvth Field Change in D-x*ti4 ► msails %M N cam®cb 6-0 ¢Duff ................. -....-..... ... ......._................ y..........,.......... _...._..._. _....._....... _ .................. .l._......___........_._....._........__ _._........:.__......... .�. _.. -_ - ......................... ...... ..�Sen.Nmcb......._.__...._. . ....._ _.........,............................................ .._.... .................. ....._.............................. .........._............._... 48.0 __.. ._...;........_..... _ ................... .. ... ...t»... .. _......... _.. -........_............................. ....._._......_i......_...._.............._. . . ....... GOD i _walerfable _. ..._... ......_.._ ._.. ............................... 66.0 77-0 t _.............<................................._......._. - _........... _........ ............... _.._. _ . ..... ..?...... ... .. .............. ........:_....:.......___....._.._...._.._._........._.. ._....................._................_................... i....._._....._...._.._._....-_..__.... ................ ..----. _...__ _....._...._ ____._..._..._._.._.. _.. _ . _ o�vw!!sm1........_.._.._.... ..._......................_I...........,.. . _._ -.......... 108.0 _......_...._.o_._.__......._.,......_........_..............._..._.,_ ......................... .................................. .-......__.. ..............__»............................................ 114.0 _.... ............................... ».. _. .._. ...._.......... .._....._.._....:................................-._.....---.. 1?J6.0 i �_. �.. i32o' ..........................---__ _.__._. . _... .... _.._............ ........_........... _......... 1ss o ; 1�s.0 = , : 136At................. ..........._.__4....._......._......Nz.. 1 _... ........,_............_.._..._..._......». ___ _.....__._. _.._. ...._._.._. . _.. _....... 6 0 ......................_....».__._ ....... _._. ...... _.»....._... _....._.t._................ ....._.........._.... -IE0.0 -_._.. _...-...-..__._.-...-- -...__._ __....___..i•_-_._-._..... -------_..------_..__....._._J._�..._ ......_ .__.__.._ .__... _........................._........._............ ........._ ._-.............. 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