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Home My WebLink AboutGeoTech Report for BLD2007-01434 - BLD Engineering / Geo-tech Reports - 7/16/2008 ontcwtcAL EsTIN(; LABORATORY c CHAD CLAYTON 501 EAST TIMBER TIDES DRIVE UNION,WASHINGTON 98592 RE: GEOTECHNICAL REPORT ADDENDU (�y SITE INFORMATION: 501 EAST TIMBER TIDES DRIVE UNION,WASHINGTON j U L 18 U�7 GPS LOCATION: N47o 21.1951 W123o 01.0581 PARCEL: #322357590281 MCCD P A N N I NG REPORT DATE: 11/07/2007 - - - - - ADDENDUM DATE: 07/16/2008 Dear Mr. Clayton: The following is an addendum to the above-noted report and reports point-by-point to the question raised by Russell LaForce of Vector Engineering. We have provided three copies for your review and distribution. 1) Landslide Activity- By reference to CZAW Maps#8 and 9, and available geology maps, this area is free of recognized deep- seated landslide features. Geologically, this is due to the nature of the glacial deposits that are locally free of sand and silt interbeds that might serve as failure surfaces. The recent rains triggered numerous relatively minor episodes of land wasting which locally caused important damage. Many of these were due, in part, to earlier construction where the engineering (if any) was not done to current standards. There appears to be little concern for failure at the proposed site. 2) Buffers- There is a set-back on the site plan of 15 feet. This is all the room available for the structure. There is no erosional buffer as the area between the Landslide Hazard Area and the proposed building area is covered in asphalt or is denuded of vegetation. 3) Collected Samples- All samples were taken by the split spoon sampler. 4) Terminology- This is a terminology problem only. The cross section is using "gravely sand" and "sandy gravel" as informal shorthand for SW and GW, respectively. 5) The Seep- The seep was considered inconsequential at the time of the original visits. We have no evidence it is of a size or geometry that allows modeling. It was plotted for the sake of completeness. 6) Upslope- The upslope was not modeled as the existing residence is already located at the base of this slope and hence lies between the slope and the proposed structure. The proposed structure will not affect the upslope stability. 10011 Blomberg Street SW,Olympia,WA 98512 1 Phone (360)754-4612 Fax#:(360)754-4848 4 7) Map Scale- The scale has been corrected to 1":= 100 feet. 8) Erosion Control- While we do include recommendations for erosion control in the report, it is for use at time of construction. If a full soil erosion and control plan is needed, it should be undertaken by an appropriate specialist approved by Mason County. We recommend that native vegetation be planted wherever possible for general erosion control. 9) Unit Cohesion- Again, the nomenclature problem seems to have created the confusion concerning the SW over GW units. The cohesion value used is the correct value for sandy Gravel (used in the model) and well graded Gravel (as described in the boring log). We appreciate this opportunity to be of service to you and we look forward to working with you in the future. If you have any questions concerning the above items, please call us at the phone number listed below. of Washz Respectfully Submitted, ro Geotechnical Testing Laboratory, Inc. 4 n 2439 �5 7-16->u it ed Gg o Curtis D Cushman Engineering Geologist CURTIS DEp.N CUSHMAN 10011 Blomberg Street SW,Olympia,WA 98512 2 Phone#:(360)7544612 Fax#:(360)754-4848 DATUM F✓)R THE SITE PLAN INCORPORATED , ----------- FILTER FABRIC MATERIAL ST WOE ROLLS VARIOUS TECHNIQUES AND SOURCES FABRIC TO . , REF WIRE RING TO ATTACH • INCLUDING THE FOLLOWING: +1� rxzx14 GAUGE WIRE Geotechnical TAPISb AND PACING,SLOPE MEASUREMENTS /'��— FABRIC OR EQUIVALENT BEARINGS H AN S USING A BRU ANGLES AND :==;" ,7� := Testing • BEARINGS USING A BRUNTON®GEO TRANSIT, ",' SITE LOCATIONS USING A GARMINO HAND HELD ---------------'`" r� GPS UNIT,TOPOGRAPHIC MAPS FROM DELORME® MASON COUNTY G.I.S. E,AND SURVEYS 82 5' / ra ADE �\ Laboratory RECORDED AT THE MASONON COUNTY ASSESSOR GEOLOGIC SITE RECONNAISSANCE OCCURRED := ON SEPTEMBER 14,2007 BY LEVINE. 140— —r Max THE SITE IS SHORT PLATTED AS LOT A OF SP#257. % ------ rX4'WOOD POSTS,STANDARD OR BURv BOTTOM OF FILTER % - BETTER OR EQUAL ALTERNATE: MATERIAL IN 6-XI2'TRENCH USES AND ACTIVITIES IN EROSION HAZARD STEEL FENCE Posts AREAS ARE SUBJECTED TO EROSION HAZARD ! ze%SLOPE AREA DEVELOPMENT STANDARDS INCLUDING THE SUBMITTAL OF A SOIL AND SEDIMENT / \�o FILTER FABRIC 6 CONTROL PLAN PREPARED BY A PROFESSIONAL - - ENGINEER 272XI4GA G WIRE EXISTIN61 FABRIC OR EQUIVALENT. ' s GROUND SURFACE r %32%SLOP 0 so ' r PROVIDE 314--1 I/I WASHED—� GRAVEL BACKFILL IN TRENCH AND ON BOTH SIDES OF FILTER 12 OAAVAIY - FENCE FABRIC ON THE SURFACE B AN S E ' Q(2• R :'' 2 W WOOD POSTS ,AREA j =' ALT.STEEL FENCE POSTS ,"o �ioPE �SLom--------- Geotechnical Services '• _ _A0 �" Y / GnISTING 1.FILTFABRICF SMALLNCE BE QA/QC Services 1.FILTER FABRIC SHALL BE PURCHASED IN A IOU ROLL OUT TO .(\ AY ; V PORT THE LENGTH OF THE BARRIER TO AVOID US2 OP JOINTS.WHEN JOINTS FJG3� A ARE NECESSARV,FILTER CLOTH SWILL BE IIPUCED TOGETHER ONLY AT Testing Services A SUPPORT POST WITH A MINIMUM 11NCH OVERLAP AND SECURELY Y NE 0 - FASTED AT BOTH ENDS TO THE POST. PROF/��O��&FO t� V" Oppp - 2.POSTS SHALL BE SPACED A MAXIMUM OF 66ET APART AND DRIVEN 3%SL E y , ADD1770N(16'x SECURELY INTO THE GROUND(MINIMUM OP%0 INCHES). EXISTING 3,A TRENCH SHALL BE EXCAVATED APPROXWATELY 8 INCHES HIDE AND 12 10011 Blomberg St.SW INCHES DEEP ALONG THE LINE OF POSTS AND UPSLOPE FROM THE BARRIER. RESIDENCE ` U% oPE Olympia,WA 98512 4.WHEN STANDARD STRENGTH FILTERFAB 18USED,AWIREMESH phone:(360)754-4812 / RRHK�� - t5 SUPPORT FENCE SHALL BE FASTENED SECIRELY TO lHE UPSLOPE SIDE T LEAST I INCH LONG,TIEE WIOFTH TRES OR MOG RINGS.THE NIRHEAVY-OM WIRE STAnA NALLUES AEXTEtm IMD THE Fax:(360)754-4848 _ _______ �TS \\A.._/ INCHES ABOVE THE O TRENCH A RIGINAL INCHO AND BHA R ACE.EXTEND MORE THAN 36 �Qi \ S.THE TO THE FENCCE AND 20INCSTRENGTHHES OFFILTEF FABRIC$ L BE EXTENDED FABRIC Z ALL BE STAPLED OR WIRED Date: 09/28/2007 INTO THE TRENCH.THE FABRIC SHALL NOT ND MORE THAN 36 Designed y__--- - -- INCHES ABOVE THE ORIGINAL GROUND SUR ACE.FI I LTER FABRIC SHALL g ed b : LEVINE __ NOT BE STAPLED TO THE EXISTING TREES. ------------- Drawn by: LEVINE 2 TAN ♦y - __ LANDS 6.AMEN EXTRA-STRENGTH FILTER FABRIC M CLOSER ACING IS Checked by:: �LEV^IN�E _ USED.THEE IRE FILMESHSWPORTFENCE OR 8EELIMINATED,IN SUCH Dwg#:09-28-07-098 A CASE,THE FILTER FABRIC IS STAPLED% RED DIRECTLY TO THE POSTS NTH ALL OTHER PROVISIONS OR AlVE NOTES APPLYINO. _ I 7.FILTER FABRIC FENCES SHALL NOT BE REMOVED BEFORE THE UPSLOPE AREA HAS- - ------ - — J FILTER REPAIRS SHALL BE MADE IMME BEEN PERMANENTLY STABIL IZED. FILTER FABRIC FENCES SHALL BE INSPECTS BAMEDMTELY AFTER EACH RAINFALL AND AT LEAST DAILY DURING PR GED RAINFALL,ANY _ - -'---- j OL TELY. 7---------- 9' -- --------------- GENERAL EROSION CONTROL NOTES; ' - - 1. EROSION CONTROL MEASURES SHALL BE IN PLACE PRIOR TO THE ___ BEGINNING OF CONSTRUCTION.THE PROJEdT ENGINEER AND THE COUNTY _ SMALL INSPECT AND APPROVE THE INSTAUlnION OF EROSION CONTROL MEASURES PRIOR TO BEGINNING CONSTRUCTION. 2.EROSION CONTROL MEASURES ARE NOT LIMITED TO THE ITEMS ' --------------------------------------- ON THIS PLAN.THE CONTRACTOR IS RESPONSIBLE FOR THE OFl INSTALLATION AND MAINTAINANCE ALL EROSION CONTROL MEASURES. `--- ` .' J -`` NO SILTATION O EXISTING OR PROPOSED DAINAGE FACILITIES _ SHALL BE ALLOWED.CARE SHALL BE TAKEN 0 PREVENT MIGRATION PROJECT NAME: n - ------ O SILTS TO OF SITE PROPERTIES. un��fJl --_✓3� -- ---- CLAYTON SITE ---------------------- 1.THE CONTRACTOR STALL MAKE DAILY SURVEILLANCE AI ALL EROSION ' `---`- CONTROL MEASURES AND MAKE ANY NECESSARY REPAIRS ORAL ROVI 501 E.TIMBER TIDES DRIVE TO THE EROSION CONTROL MEASURES.THE CONTRACTOR SHALL PROVIDE ADDITIONAL EROSION CONTROL MEASURES AS DETERMINED NECESSARY --� 'to _ ` BY THE COUNTY INSPECTOR ND'OR THE PROJECT ENGINEER.FAILURE UNION, WASHINGTON J -- TO OMPLYREQUIREMENTS IREMEWITHAY LOCAL IN DVIL PE ALTIIESSEICONTROL PARCEL 322357590281 ''-' - AGAINST THE CMAYRESULTINCAVILPENALTIES BEING LEVIED \� '- __ -----'--'�`�` AGAINST THE CONTRACTOR AND/OR PROJECT ONMER. --------- _ __ 4.DURING THE NET SEASON(NOVEMBER TO MARCH)ALL DISTURBED SOILS -``-- ~- SHALL BE STABILIZED WTISN 48 HOURS AFTER STOP OF WORK EROSION CONTROL MEASURES SMALL INCLUDE,BUT NOT BE LIMITED TO, - —� _-- - COVERINGTETING,EFFECTEDAREA IMG.JUTENCLUDING MATTING,POIL ES STRAW PLASTIC SHEETING,STRAW MATTING.JUTE MATTING,STRAW MULCH. --" ^ OR HOOD CHIPS.SEEDING OF THE DISTURBED AREAS SHALL TAKE U\\ PCE AS NEITHER EITR PERMITS. ,- ------ 5.ALL SEEDED OR SODDED AREAS SHALL BE CHECKED REGULARLY TO MAKE SURE VEGETATIVE COVERAGE IS COLIETE.AREAS SMALL Be -- %' REPAIRED,RESEEDED,AND FERTILIZED AS REQUIRED. SCALE: 1" = 100 FEET ----- :' 6.TRACING OF SOIL OFFSITE WILL NOT BE ALL D.IF ANY SOILS TRA'KED ONTOA COUNTY STREET,IT SMALL E REMOVED BY THE END O THAT ACRKING DAY.ANY FURTNERTRACi OMUO WILL THEN SEPREVENTEDBY SWEEPING OR WASHING THE VEHICLES TIRES BEFORE DRWNG ONA COUNTY STREET. 0 50 100 700 --___- 7.NO MORE THAN 500 LF OF TRENCH ONA DONE 6LOPE OF MORE THAN 6 L. 4� PERCENT SMALL BE OPENED ATONE TIME. I C.1. 10 -r- B.EXCAVATED MATERIAL SHALL BE PLACED ON THE UPHILL SIDE O TRENCHES. 8.TRENCH DEVMTERING DEVICES SHALL BE DIS�=IGED IN A MANNER THAT WILL NOT ADVERSELY AFFECT FLOWNG STREAMS.b1UIMAGE SYSTEMS OR OFFSITE PROPERTIES. SCALE:1 inch=100 feet •�Q�II�� ____ 10.ALL STORM SEWER INLETS RECEIVING RUNOF FROM THE PROJECT DURING 40 ,_ CONSTRUCTION SHALL BE PROTECTED 50 T3EDIMENT{ADEN WATER -�--- WILL BE FILTERED BEFORE ENTERING THE TH RIEYANCE SYSTEM. 1 I.ALL OPF-BITE CATCH BASINS IMMEDATELY A CENT TO THE SITE SMALL BE PROTECTED FROM SILTATION. FIGURE /1 % /V` KL) •- �' qv� �� /'" ______-- 12 ALL DISTURBEDAREAS SHALL BE BEEDEp OR ODDER UPON COMPLETION OF WORK THE CONTRACTOR SMALL BE RESt.I.LE TO ENSURE THAT COMPLETE COVER=THE DISTURBED AR 8 IS PROVIDED B THAT GROWN OF THE VEGETATION IS ESTABUSHE _ /' 13.wo CATCH BASINS SMALL TRAP SEDIMENT OR FILTER FABRIC MUST BE 5 I I PLAN __ PLACED UNDER GRATE UNTIL VEGETATION IS 9STABIJSHED. ECEI'T,/. DEC 2 6 2007 MASON COUNTY GEOTECHNICAL REPORT 501 TIMBER TIDES DRIVE UNION, WASHINGTON TO BE KEPT (NTHE FILE PREPARED FOR CHAD CLAYTON BY GEOTECHNICAL TESTING LABORATORY OLYMPIA, WASHINGTON NoVEM3ER 7, 2007 GEOTECHWAL TEmINO LABORATORY CONTACT INFORMATION PREPARER INFORMATION GTL PROJECT NUMBER: 07-0534 CONTACT: LANCE LEVINE ADDRESS: 10011 BLOMBERG STREET SOUTHWEST OLYMPIA,WASHINGTON 98512 TELEPHONE: (360)754-4612 FACSIMILE: (360)754-4848 EMAIL ADDRESS: GEOTESTLAB@COMCAST.NET CLIENT INFORMATION CLIENT: CHAD CLAYTON TELEPHONE: (360)898-1047 BILLING ADDRESS: 501 EAST TIMBER TIDES DRIVE UNION,WASHINGTON 98592 SITE ADDRESS: 501 EAST TIMBER TIDES DRIVE UNION,WASHINGTON 98592 PARCEL: 322357590281 GPS LOCATION: N470 21.195'W123°01.058' #07-0534 10011 Blomberg Street SW,Olympia, WA 98512 2 Phone#: (360) 7544612 Fax#: (360)754-4848 GEOTECHNICAL TESTING LABORATORY SCOPE OF UNDERSTANDING CHAD CLAYTON 501 EAST TIMBER TIDES DRIVE UNION,WASHINGTON 98592 RE: GEOTECHNICAL REPORT 501 EAST TIMBER TIDES DRIVE UNION,WASHINGTON 98592 PARCEL 322357590281 N47o 21.1951 W123o 01.0581 Mr. Clayton: As per your request,we have conducted a soils exploration, foundation evaluation, and slope stability analysis for the above-mentioned parcel. The results of this investigation,together with our recommendations, are to be found in the following report. We have provided three copies for your review and distribution. Several representative soil samples were submitted for laboratory testing from the project site. The data has been carefully analyzed to determine soils bearing capacities, footing embedment depths and building setback distances. The results of the exploration and analysis indicate that conventional spread and continuous wall footings appear to be the most suitable type of foundation for the support of the proposed structure. Some variability was encountered in comparing the soil profiles of the site. Net allowable soil pressures, embedment depth, and total expected settlements have been presented for the site later in the report. We are also a full service laboratory that can meet all your building, testing(compaction, asphalt, concrete), and special inspection needs. We appreciate this opportunity to be of service to you and we look forward to working with you in the future. If you have any questions concerning the above items,the procedures used,or if we can be of any further assistance please call us at the phone number listed below. { Wash. e o Respectfully Submitted, GEOTECHNICAL TESTING LABORATORY 1r, Harold Parks,L.G.,L.E.G. nglneering Geologist Principal � s e d G e o�oQ`e �,�'01 1;P,RuLD PA IRKS Ex f[rr-FS 7-31-0$ EXPIRES SIGNED #07-0534 10011 Blomberg Street SW, Olympia, WA 98512 3 Phone#: (360)754-4612 Fax#: (360)754-4848 GEOTECHNICAL VESTING LABORATORY TABLE OF CONTENTS lCONTACT INFORMATION.....................................................................................................................................2 SCOPEOF UNDERSTANDING ...............................................................................................................................3 TABLEOF CONTENTS............................................................................................................................................4 jINTRODUCTION.......................................................................................................................................................5 SITECONDITIONS...................................................................................................................................................6 Surface Conditions........................ GEOLOGICALLY HAZARDOUS AREAS...............................................................................................................8 Landslide Hazard Classification.............................................................................................................................8 Seismic Hazard Classification................................................................................................................................8 Erosion Hazard Classification ................................................................................................................................9 Site Geology SiteSoils............................................................................................................................................................... I I SubsurfaceExplorations....................................................................................................................................... 11 SubsurfaceConditions.......................................................................................................................................... I 1 BoringLog............................................................................................................................................................ 12 Recommendations for Suitability of Onsite Soils as Fill...................................................................................... 13 1 Shear Method........................................................................................................................................................ 13 SlopeStability and Analysis................................................................................................................................. 14 i Recommendations for Building Setback............................................................................................................... 16 LiquefactionHazard.............................................................................................................................................. 17 SeismicHazard ..................................................................................................................................................... 17 Recommendations for Erosion Control ................................................................................................................ 17 EARTHWORK......................................................................................................................................................... 18 Recommendations for Site Preparation ................................................................................................................ 18 Recommendations for Structural Fill.................................................................................................................... 18 Recommendations for Cut and Fill Slopes ........................................................................................................... 18 Recommendations for Foundation Support.......................................................................................................... 19 Recommendations for Floor Slab Support............................................................................................................20 Recommendations for Retaining Walls................................................................................................................20 Mason County Prescribed Wall Design................................................................................................................22 Recommendations for Retaining Wall Alternatives.............................................................................................24 Recommendations for Site Drainage....................................................................................................................24 SepticImpact.........................................................................................................................................................24 CONCLUSIONS AND RECOMMENDATIONS....................................................................................................24 General..................................................................................................................................................................24 REPORT LIMITATIONS AND GUIDELINES FOR USE....................................................................................................25 References.............................................................................................................................................................26 APPENDIX..................................................................................................................................................................28 AdditionalSite Photos..........................................................................................................................................29 LaboratoryResults................................................................................................................................................30 ShearResults.........................................................................................................................................................32 WellLogs..............................................................................................................................................................33 Figure1 Vicinity Map...........................................................................................................................................36 Figure2 Site Plan................ .......................................................................37 Figure 3 Erosion Control Notes..................................................................................................38 Figure4 Cross-section............................................................................................................39 907-0534 10011 Blomberg Street SW, Olympia, WA 98512 4 Phone#: (360) 754-4612 Fax#: (360) 754-4848 GEOTEC NICAL TESTING LABORATORY INTRODUCTION This report summarizes the results of our geotechnical consulting services for a proposed addition to the existing single-family residence. The addition will be located to the north of the existing residence. The report has been commissioned by Chad Clayton. The site (0.85 acres) is located along the north-facing hillside overlooking the Hood Canal (see site photo below). The site is approximately 3.8 miles east of Union, Washington. The site is accessed from the existing driveway off Timber Tides Drive. The GPS location of the site is shown relative to the surrounding area on the Vicinity Map,Figure 1. z, xa t+l, f �~ View Looking South at Lower Slope , Our understanding of the project is based on our discussions with you and our explorations and review of the site. We understand that the parcel is to be developed with an addition to the existing structure. In general, grading will consist of the excavation of the foundation and footings. The approximate layout of the site is shown on the Site Plan,Figure 2. j 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 includes the following: 1. A review of the available geologic,hydrogeologic,and geotechnical data for the site area. 2. A geologic reconnaissance of the site area and surrounding vicinity. 3. Investigation and identification of shallow subsurface conditions at the site by characterizing the exposed soil and by reviewing published well logs. 4. Comparison of site to published geologic maps, previous field investigations, and open file reports. Inspection of aerial photographs to determine the geomorphology of the site. 5. Laboratory grain size and shear angle analysis for the soil samples collected from the site. 6. Evaluation of the landslide, erosion, and seismic hazards at the site per the Mason County Critical Areas Ordinance regulations(December 27, 2006). 7. Building setbacks determined from dynamic slope stability modeling. 8. Geotechnical recommendations for site grading including site preparation, subgrade preparation, fill placement criteria(including hillside grading), temporary and permanent cut and fill slopes, drainage and typical erosion control measures(Figure 3). #07-0534 10011 Blomberg Street SW, Olympia,WA 98512 5 Phone#: (360) 754-4612 Fax#: (360)754-4848 EOTECHNICAL TESTING LABORATORY The steepest slope measured onsite was approximately vertical along the existing southern cut slope. This slope will be approximately 55 feet from the proposed addition. Therefore,Mason County requires that a geotechnical report be prepared in accordance with the Critical Areas Ordinance. SITE CONDITIONS SURFACE CONDITIONS i The proposed building site is located in an area of moderate residential development in the Puget Sound glacial upland along the southern hillside overlooking the Hood Canal (see aerial photos below). The central portion of the site has been previously developed with a single-family residence and septic drainfield. The sloping portions of the site are well vegetated. The site has a predominant northern exposure. Site elevations range from approximately 140 to 290 feet. TerraServer-USA Aerial Photo WA DOE Coastal Photos r We conducted a reconnaissance and subsurface exploration of the site area on September 14, 2007 by Lance Levine under the direction of Harold Parks. The purpose of the site reconnaissance is to physically observe the property and adjacent properties to identify any recognized geologic conditions. Photographs and visual observations were documented. Site-specific features were mapped; soil logs were recorded. No grading has occurred recently. The following photo illustrates the proposed building location of the site. j - Proposed Building Location #07-0534 10011 Blomberg Street SW,Olympia, WA 98512 6 Phone#: (360)754-4612 Fax#: (360) 754-4848 EOTEC'HNIC'AL TESTING LABORATORY The general topography of the site area indicates that drainage flows toward the northern driveway and then to the west from the proposed building(addition)location. The site plan is included as Figure 2. No surface water flow was observed onsite. No evidence of active surface erosion was observed onsite. No ponding of water was observed throughout the site. Slumping and sloughing were not observed onsite. No evidence of deep-seated slope instability was observed onsite. A small seepage is located approximately 50 feet to the south of the proposed building location, see photo right. The seepage is conveyed to the west towards Timber Tides Drive; this direction is away from and downslope of the proposed building =" location. Onsite trees were observed to be straight and vertical. No upland water bodies or wetland features were observed during the { site reconnaissance or through the inspection of aerial photographs seepaRe within '/2 mile to the south. Possible small wetland areas may exist within 1 mile of the site. The maximum slope is approximately vertical along the existing southern cut slope. To the north of the proposed building location, the slope is approximately 60 percent. The lower northern slope is approximately 26 percent. The selected building location has a slope of approximately 2 to 5 percent, see photo below. The existing septic drainfield has a slope of approximately 3 percent. All slope angles were measured using a Brunton inclinometer. The site is protected with vegetation common to the Northwest. The vegetation includes fir, alder, cedar, hemlock, pine, and madrone trees as well as salal, rhododendron, manzanita, huckleberry, bracken fern, sword fern, ivy,blackberry,and grasses. _u- i Proposed Building Location #07-0534 10011 Blomberg Street SW, Olympia, WA 98512 7 Phone#: (360)754-4612 Fax#: (360) 754-4848 GEOTEC NICAL TESTING LA130RATORY GEOLOGICALLY HAZARDOUS AREAS LANDSLIDE HAZARD CLASSIFICATION The Mason County Critical Areas Ordinance(17.01.100A1)defines a landslide hazard area as: The following shall be classified as Landslide Hazard Areas: a. Areas with any indications of earth movement such as debris slides, earthflows, slumps and rockfalls (see figure F.100). b.Areas with artificial oversteepened or unengineered slopes, i.e. cuts or fills. c.Areas with slopes containing soft or potentially liquefiable soils. d. Areas oversteepened or otherwise unstable as a result of stream incision, stream bank erosion, and undercutting by wave action. e. Slopes greater than 15%(8.5 degrees) and having the following: i. Hillsides intersecting geologic contacts with a relatively permeable sediment overlying a relatively impermeable sediment or bedrock(e.g. sand overlying clay); and ii. Springs or groundwater seepage. f. Any area with a slope of forty percent or steeper and with a vertical relief of ten or more feet except areas composed of consolidated rock A slope is delineated by establishing its toe and top and measured by averaging the inclination over at least ten feet of vertical relief. The subject site meets the qualification of a landslide hazard area due to the adjacent slopes (northern) that are greater than 40 percent and more than 10 feet in vertical height (17.01.100A1f). This slope will be over 20 feet from the proposed building location. SEISMIC HAZARD CLASSIFICATION The Mason County Critical Areas Ordinance(17.01.102A)defines a seismic hazard area as: 1.Areas susceptible to ground failure including the following: a.Areas with mapped geologic faults until proven inactive; b. Deep road fills and areas of poorly compacted artificial fill; c.Areas with artificially steepened slopes (i.e. old gravel pits); d. Postglacial stream, lake or beach sediments; e. River deltas; f.Areas designated as potential Landslide Hazard Areas; g. Bluff areas;and h.Areas underlain by potentially liquefiable soils 2. The following criteria may be used as a guide by the County to indicate areas that have a higher likelihood of meeting the classification criteria above: a. Areas identified on the Coastal Zone Atlas of Washington, Volume 9, Mason County as Af, Qal, Qa2, Qvc, Qls, Qos and Qp. b. Areas identified on the Mason County Soil Survey Map as having slopes greater than 15 percent. c. Faults identified on "Map Showing Known or Suspected Faults With Quaternary Displacement in the Pacific Northwest", A.M. Rogers, T.J. Walsh, W.J. Kockelman and G.R Priest, US Geologic Survey, 1996; or described in "Active Faulting Investigations on the Canyon River Fault, Southern Olympic Range, Washington", T.J. Walsh and KG. Neal, U.S. Geologic Survey, 1997. d. Areas underlain by potentially liquefiable soils as shown "Liquefaction Susceptibility Map of Mason County, Washington" by Stephen P. Palmer, Sammantha L. Magsino, James L. Poelstra, Eric L. Bilderbacl; Derek S. Folger, and Rebecca A. Niggemann, September 2004 #07-0534 10011 Blomberg Street SW, Olympia, WA 98512 8 Phone#: (360)754-4612 Fax#: (360) 754-4848 llfEOTECHNICAL TESTING LABORATORY This site does qualify as a seismic hazard area because the site is categorized as, "l.f. Areas designated as potential Landslide Hazard Areas." EROSION HAZARD CLASSIFICATION The purpose of the Erosion Hazard Section (17.01.104A) is to identify areas that present potential dangers to public health and safety, and to prevent the acceleration of natural geological hazards, and to neutralize the risk to the property owner from development activities. 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 gravelly sandy loam("Hb') d. Kitsap silt loam rKc') The soils at the site are mapped as Alderwood gravelly sandy loam(Ad). This site does meet the technical criteria of an erosion hazard area. SITE GEOLOGY Puget Sound LiDAR Consortium The site is generally situated within the Puget Sound ' glacial upland. Multiple glacial advances deposited .w the onsite material. The near surface material was deposited during the most recent Vashon stade(stage) of the Fraser glaciation that occurred between about 9,000 and 11,000 years ago. Weathering and erosion has occurred since. The figure (right) is a LiDAR image at a 12-feet resolution. In the local vicinity, ridgelines trend northeast to southwest. Drainages trend to the northwest towards the Hood Canal.The soils are composed of firm to dense gravelly sand fir x, r underlain by well-cemented and well-graded dense glacial advance outwash material (sandy gravel), see . `, following photos. The vertical boring advancement was slow due to the inherent cementation and large gravel. A description of the onsite soils is included in the"Soil Logs"section of this report. The following geologic excerpts are for the educational purposes of the client and not necessarily for the review staff at Mason County. The following photos portray the onsite material. I #07-0534 10011 Blomberg Street SW, Olympia, WA 98512 9 Phone#: (360)754-4612 Fax#: (360)7544848 EOTECHNICAL TESTING LABORATORY The Geologic Map of Washington—Northwest Quadrant(2002)has mapped the site geology as advance outwash deposits(Qga)of continental glacial origin. The report reads: Advance outwash — Glaciofluvial sand and gravel and lacustrine clay, silt, and sand deposited during the advance of glaciers; sandy units commonly thick, well sorted, and fine grained, with interlayered coarser sand, gravel, and cobbles; locally contains nonglacial sediments and deposits mapped as transitional between glacial and nonglacial. Includes the Colvos and Esperance Sand Members of the Yashon Drift and part of the Yashon Drift undivided. S qR 1 y s } �9 W 1 t � r Sand} Gravel ' The Geologic Map of the Shelton 1:100,000 Quadrangle, Washington, by Logan (2003) describes the site as glacial advance outwash(Qga). The glacial advance outwash is described as: Advance outwash, late Wisconsinan (Pleistocene)—Glaciofluvial sand and gravel and lacustrine clay, silt, and sand deposited during the advance of glaciers; sandy units commonly thick; well sorted, and fine grained, with interlayered coarser sand, gravel, and cobbles and silt rip-up lag deposits at their base;may contain nonglacial sediments;generally overlain by till. The Geologic Map of Southeastern Mason County, Washington, USGS Water-Supply Bulletin 29 by Noble and Molenaar(1970)describes the site as advance outwash. The advance outwash(Qva)is described as: Gravel and sand, with some silt and clay at base. Unconsolidated and generally is in discontinuous strata.. Underlies till in most of area and up to 200 feet thick Yields moderate to large quantities (20-800 gp.m) of water where gravel and coarser sand facies below water table. �F t Y o Xti3-Z.� t_ - �� .a V Gravelly Sand to Sandy Gravel I #07-0534 10011 Blomberg Street SW, Olympia, WA 98512 10 Phone#: (360)754-4612 Fax#: (360)754-4848 EOTECHNICAL TESTING LABORATORY SITE SOILS The Soil Survey of Mason County, Washington, USDA Soil Conservation Service(1960)has mapped the site soils as an Alderwood gravelly sandy loam,30 to 45 percent slopes(Ad). The report reads: The Alderwood soils typically formed from gravelly glacial till. They are described as having good natural drainage. Typically, there is no occurrence of a high water table. Internal drainage is described as medium. An erosion hazard may exist if the vegetation is removed. , Surficial Material in Northern Portion of Site �� SUBSURFACE EXPLORATIONS Subsurface conditions at the site were evaluated by boring and logging the exposed building site soil,probing, and reviewing available well logs. A small seepage was observed to the south of the existing single-family residence. Groundwater was not encountered at the proposed building location and is beyond the scope of this report (59 to 460 feet below ground surface). See the provided wells logs in the Appendix. Soil logs were field logged (visually) using the Unified Soil Classification System (USCS). The soil logs were recorded by Lance Levine on September 14, 2007. Soil colors were visually determined using the Munsell Soil Color Charts,revised 1992. Grab samples were collected by means of split spoon sampler via test boring. The samples were sealed in Ziploc bags, labeled, and transported to our soils laboratory. Soil gradations were determined by laboratory test method ASTM D-2487 that utilizes the Unified Soil Classification System. The soils laboratory has the following certifications,accreditations, or qualifications: AASHTO American Association of State highway and Transportation Officials AMRL AASHTO Materials Reference Laboratory CCRL Cement and Concrete Reference Laboratory A2LA American Association for Laboratory Accreditation ICC International Code Council Army Corp.of Engineers SUBSURFACE CONDITIONS In general, stiff to dense Alderwood gravelly sandy loam (gravelly sand) was observed throughout the site. Vashon Stade glacial advance outwash material (sandy gravel) was observed below the Alderwood material. Specific soils information is contained in the following"Soil Logs" section of the report. Depth to competent soil is approximately 3 to 12 inches throughout the proposed building location. We recommend inspection of all earthwork activities. #07-0534 10011 Blomberg Street SW,Olympia, WA 98512 11 Phone#: (360)754-4612 Fax#: (360)754-4848 OTECHNIC L TESTING LABORATORY Groundwater was not observed or encountered in the test boring. Minor seepage was observed along the existing southern cut slopes, see photo below. Seepage a � _ _ �: View Looking East BORING LOG Date: 9/14/2007 File#: 07-0534 Boring Log#: 1 Client: Clayton,Chad Boring Type: 6"Hollow Stem Auger Depth Drilled: 19 feet Location: N47°21.195' W1231'01.058' Elevation: 194 feet Location: 501 East Timbertides Drive,Union Elevation: 194 feet Depth Laboratory Change (Ft) Description in Soils %M N Field Description 1.0 Disturbed Driveway 2 0 Dark brown(5YR5/3)silty sandy gravel,dry,dense,well- graded,round to sub-round gravels up to 4 inches 3.0 4.0 @ 3'-4'more sand,less gravel 5.0 SW,Well-graded Sand with Gravel 7 3% 20 7.0 8.0 Water added @ 8'increasing gravel 9.0 10.0 Refusal Grayish brown(10YR5/2)sandy gravel,round up to 2 inches well-graded,cemented 11.0 12.0 GW,Well-graded Gravel 13.0 14.0 15.0 No blowcounts due to slope angle 18.0 „19.0 TD—19 feet— No Groundwater #07-0534 10011 Blomberg Street SW,Olympia, WA 98512 12 Phone#: (360)754-4612 Fax#: (360)754-4848 GEOT C NICAL 'BESTING LABORATORY RECOMMENDATIONS FOR SUITABILITY OF ONSITE SOILS AS FILL Onsite soils may be considered for use as structural fill if industry standards are satisfied. Fill material requirements are found on page 9-31 of the WSDOT Standard Specifications 2006. In general, the native soils (sand, silt, and gravel) encountered on the site must have less than 10 percent fines (material passing the US No. 200 sieve) to be suitable for use as structural fill. Laboratory analysis of the onsite material indicates that the onsite material sampled may be used as structural fill(gravel base). See the laboratory results in the Appendix. SHEAR METHOD A collected grab sample was tested to determine shear angle and cohesion. Results of the shear test are listed below. The standard method of test was method AASHTO T 236-92, Direct Shear Test of Soils Under Consolidated Drained Conditions. Specifically,the disturbed sample is remolded into the shear box. A computer records the test readings. The data file is imported into Excel. The three peak strengths were hand picked by choosing, from the individual trials, the break point of the curve. Utilizing the concepts of the Mohr circle analysis,the maximum shear stress is plotted against the normal stress. A line is drawn to"best fit'the peak data points. The shear angle is the measured angle of the "best fit' line relative to the abscissa. The cohesion is determined by the intersection of the "best fit' line and the ordinate. See the shear related figures in the : Appendix. Native soil density was determined by the Bulk Density test method(ASTM C-29/C-29M-97 (2003)). The soil was determined to have a dry density of 131 pcf. The sample was determined to have the following characteristics: Unit weight 131 pcf Cohesion 200 psf Shear angle 380 Terzaghi Equation Based on our laboratory testing conducted on the sample of material collected from subject site, we have calculated the theoretical ultimate bearing capacity. The following Terzaghi formula calculates the ultimate bearing capacity. Using the Figure 6.3, page 173 Terragiu Equation is gig by the following fonnila I by Prakash, the bearing yBNy) Qa=B(cN. yD+ fNq /z+, capacity factors are determined from the shear angle. Using a factor of c W Y Df Nq 0.5 Y B Ny safety of three (3), the 1 65 131 1 55 0.5 131 2 77 theoretical maximum bearing capacity is equal to 5,700 psf using a shear Utimate Bearing Capacity is: 17357 angle of 3 8°. See the Using a Factor of Safety of 3 5786 subsequent spreadsheet calculation. The IBC c=unit cohesion 1 (Table 1804.2) lists the Y=sal density 131 allowable foundation B=footing width 2 pressure as 2,000 psf for a D(f)=depth of footing 1 sandy gravel(SW). N(c)=bearing capacity factor 65 N(q)=bearing capacity factor 55 N(Y)=bearing capacity factor 77 #07-0534 10011 Blomberg Street SW, Olympia, WA 98512 1; Phone#: (360)754-4612 Fax#: (360)754-4848 I I GEOTECHNICAL TESTING LABORATORY SLOPE STABILITY AND ANALYSIS In general, the undisturbed native soils of the site consist of a mixture of variable amounts of sand and gravel. These soil materials are in a dense and cemented condition except where they have been disturbed by weathering activity. No evidence of significant erosion was observed onsite at the time of our investigation. Instability of this nature is typically confined to the upper weathered or disturbed zone, which has been disturbed and has a lower strength. Raveling and sloughing were not observed onsite. 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. Over excavation may be necessary to ensure the removal of deleterious material. These processes can be managed and the risk reduced through proper construction of the residence. Erosion control recommendations in the slope and buffer areas are provided in the "Building Setback" and"Erosion Control"sections of this report. Excavation and back-filling will occur based on appropriate engineering and earthwork recommendations found in the following"Earthwork" section. Grading in the building portion of the site should be conducted in accordance with geotechnical recommendations provided herein. i Our findings were compared with the only slope stability resource pertaining to the subject site. The "" '' '' Coastal Zone Atlas Relative Slope Stability of the Southern Hood Canalc Area,by R.J.Carson(1977)classifies the site area as v Class 2. Class 2 is described as, � Areas believed to be stable under normal , conditions, but may become unstable if disturbed by man's activities, if slope is �,� u�. , oversteepened by erosion, or if subjected to strong seismic shaking: Slopes generally steeper than 15 percent, but may be less in some areas of weak geologic materials. Includes areas underlain by: well-drained sand and gravel, mostly on valley sides that - lack known slope failures; glacial till with s steep slopes; and bedrock. = 6 The Coastal Zone Atlas, Volume 9, Mason County (MA-9) maps the site as Vashon Advance Outwash —� -__--- Scale 1:24,000 (Qva). The chance of flooding is less than one —— a ; . percent. Permeability is described as high, while runoff potential is low. Infiltration is moderate on _ natural slopes and high on cut slopes. Springs at the bases of slopes are common (a seep was observed to ithe south of the existing residence). The slope stability is described as "intermediate." Resources by Rogers and Walsh detailing faults in the Puget Sound were reviewed. No known faults are mapped in the vicinity J of the subject site. 407-0534 10011 Blomberg Street SW,Olympia, WA 98512 14 Phone#: (360)754-4612 Fax#: (360)754-4848 EOTEC NWAL TESTING LABORATORY i Slope stability was modeled using the GeoStudio 2004 program (version 6.20) in both static and dynamic conditions (ca = 0.15). Factors of safety were determined using Bishop's, Janbu, and the Morgenstem-Price methods. The site was modeled using two layers of cemented gravel and sand (see Figure 4 Cross-section). The material was determined to have a unit weight of 131 pcf, cohesion of 200 psf, and a shear angle (�) of 381 (see Appendix for shear test results). Since groundwater was not observed in the test boring, the site was modeled using "dry" or unsaturated conditions. The footings will be founded on undisturbed and unyielding native material;hence,the surficial material was not used in the slope models. Under static conditions,the slopes remained stable to deep-seated and shallow failure. See Figure 4 for the cross- sections. The factor of safety is equal to 2.36 for section "A." Under dynamic loading, the 3328 computations demonstrated that the slope is not susceptible to surficial raveling or large deep-seated failure. The following figure illustrates the moment factor of safety for section "A" under the existing conditions. The critical slip surface factor of safety is equal to 1.74 for section "A." Mason County code requires a dynamic factor of safety to be at least 1.1 at the proposed building location. The minimum slip surfaces are labeled on the following figures. The following figures exhibit the need for a building setback of 15-feet from the crest of the steep slopes. All foundation elements shall be constructed on native material or engineered fill material. The current proposed building location meets the previous requirements. Static I' Clayton Site -- Section A •• ,••••• N • • 240 .a� 230 �2.36 220 Proposed , 4__ 210 Addition • Description. ravelly Sand • 200 VVt 131 • O Cohesion:200 190 Phi:38 Boring 1 N 180 ` W 170 160 7 150 r,� r 140 0 25 50 75 1J0 `z5 150 225 250 Distance (ft) #07-0534 10011 Blomberg Street SW,Olympia, WA 98512 15 Phone#: (360) 754-4612 Fax#: (360)754-4848 GEOTECHNICAL TESTING LABORATORY D�nanlic Clayton Site -- Section A : ; ' • • • 240 1.74t • 230 220 • ' Proposed 210 Addition 15, . , • �� Descriptio . ravelly Sand Setback • . . ,,,� 200 Wt 131 p Cohesion:200 190 Phi:38 Boring 1 v 180 W 170 Minimum Slip Surface 160 150 ._,..,. 0 25 50 75 100 125 150 175 200 225 250 Distance (ft) RECOMMENDATIONS FOR BUILDING SETBACK The building setback may be measured from the bottom of the footing to the face of the steep slope in accordance with the International Building Code (1805.3.1), see figure to right. As previously discussed, weathering, erosion and the resultant surficial sloughing and shallow landsliding are natural processes that affect slope Setback areas. Slumping and sloughing were not observed onsite. To manage and reduce the potential for these natural processes, we recommend the following: ➢ No drainage of concentrated surface water or significant sheet flow onto the sloped areas. ➢ No filling within the setback zone. ➢ Maintain a 10 buffer(driveway)from the landslide hazard area. #07-0534 10011 Blomberg Street SW,Olympia, WA 98512 16 Phone#: (360)754-4612 Fax#: (360)754-4848 EOTECHNICAL TESTING LABORATORY LIQUEFACTION HAZARD The surrounding undisturbed slopes, adjacent to the existing driveway, are well vegetated. The absence of springs and seeps along the slope faces below the proposed building location and the lack of groundwater encountered during the test boring signifies that groundwater is at least 30 feet below the ground surface. With the local well logs available,we conclude the groundwater is approximately 59 to 460 feet below the ground surface. Shaking of the already dense glacial advance outwash is not apt to produce a denser configuration and subsequently excess pore water pressures are not likely to be produced. Lacking shallow groundwater,the mixed material (gravels, sands, and minor silt) is well-graded and partially cemented and is not a likely candidate for liquefaction concerns. Grain-size analyses are found in the Appendix. Based on our review of the subsurface conditions, we conclude that the site soils are only mildly susceptible to liquefaction. The following geologic excerpts are for the educational purposes of the client and not necessarily for the review staff at Mason County. The Liquefaction Susceptibility Map of Mason County, Washington by Palmer, Magsino, Poelstra, Bilderback, Folger, and Niggemann(September 2004)maps the site area as having a very low to low liquefaction potential. The Site Class Map of Mason County, Washington by Palmer, Magsino, Bilderback, Poelstra, Folger, and Niggemann(September 2004)maps the site area as site class C to D. Site class C is a very stiff soil or soft rock and site class D is a stiff soil. SEISMIC HAZARD According to the Seismic Zone Map of the United States contained in the 2006 International Building Code(IBC), the project site is located where the maximum spectral response acceleration is 45 percent of gravity(g). Based on the subsurface conditions observed at the site,we interpret the site conditions to correspond to a seismic Soil Profile Type D, for Stiff Soil, as defined by Table 1613.5.2 (IBC). This is based on standard penetration rates utilizing a 140 pound hammer and 2 inch split spoon sampler(penetrometer). The shallow soil conditions were assumed to be representative for the site conditions beyond the depths explored. RECOMMENDATIONS FOR EROSION CONTROL Active surface erosion was not observed on or surrounding the subject site. Evidence of ponding was not observed onsite. It is our opinion that the potential erosion hazard of the site is not a limiting factor for the proposed development. Removal of natural vegetation should be minimized and limited to the active construction areas. Yard landscaping around the home is permissible, but understory growth on the slopes should be encouraged as much as possible as a deterrent to erosion. Hazard trees located on steep slopes may be removed only if the stumps remain to deter 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. Typical erosion control notes and a silt fence detail are included on Figure 2 j Site Plan. Any re-contouring of the site will create a need for erosion control measures as recommended above. I #07-0534 10011 Blomberg Street SW, Olympia, WA 98512 17 Phone#: (360)754-4612 Fax#: (360)754-4848 EOTECHNICAE TESTING LABORATORY EARTHWORK RECOMMENDATIONS FOR SITE PREPARATION All areas to be excavated should be cleared of deleterious matter including any existing structures, debris, duff, and vegetation. Based on our observations, we estimate that stripping on the order of 3 to 12 inches will be necessary to remove the root zone and surficial soils containing organics. Areas with deeper, unsuitable organics should be expected in the vicinity of depressions or heavy vegetation. Stripping depths of up to 3 feet may occur in these areas. These materials may be stockpiled and later used for erosion control and landscaping. Surficial material that cannot be used for landscaping or erosion control should be removed from the project site. No foundation elements shall be constructed on"untested"fill material. Where placement of fill material is required, the exposed subgrade areas should be proof-rolled to a firm and prior to placement of an fill. We recommend that trees be removed with the roots unless unyielding surfacep p y located on a slope. Excavations for tree stump removal in any building area should be backfilled with structural fill,compacted to the density requirements described in the"Structural Fill"section of this report. If structural fill is needed, we recommend that a member of our staff evaluate the exposed subgrade conditions after removal of vegetation and topsoil stripping is completed. Any soft, loose or otherwise unsuitable areas delineated during foundation preparation or probing should be compacted, if practical, or over-excavated and replaced with structural fill, based on the recommendations of our report. RECOMMENDATIONS FOR STRUCTURAL FILL All fill material should be placed as structural fill. The structural fill 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 structural fill will depend on the gradation and moisture content 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. During wet weather,we recommend the use of well-graded sand and gravel with less than 9 percent(by weight)passing the No. 200 sieve based on that fraction passing the 3/4-inch sieve. Material placed for structural 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. RECOMMENDATIONS FOR CUT AND FILL SLOPES All job site safety issues and precautions are the responsibility of the contractor providing services and/or work. The following cut/fill slope guidelines are provided for planning purposes. #07-0534 10011 Blomberg Street SW,Olympia,WA 98512 18 Phone#: (360)754-4612 Fax#: (360)754-4848 GEOTECHNIC L TESTING LABORATORY Temporary cut slopes will likely be necessary during grading operations. As a general guide,temporary slopes of 1.5 to 1 (horizontal to vertical) or flatter may be used for temporary cuts in the upper 3 to 4 feet of the glacially consolidated soils that are weathered to a loose/medium-dense condition. Temporary slopes of 1 to 1 or flatter may be used in the unweathered dense to very dense sands and gravel. These guidelines assume that all surface loads are kept at a minimum distance of at least one half the depth of the cut away from the top of the slope and that significant seepage is not present on the slope face (due to recent rain events). Flatter cut slopes will be necessary where significant raveling or seepage occurs. Surface drainage should be directed away from all slope faces. Straw,hay, or jute matting shall be used to cover the exposed soils until permanent vegetation is established. All slopes should be seeded as soon as practical to facilitate the development of a protective vegetative cover or otherwise protected. Proposed Building Location �- A�r - e >yy - ram RECOMMENDATIONS FOR FOUNDATION SUPPORT Where foundation elements are located near slopes between 5 and 30 percent, the footings should be located a minimum of 2 times the footing width from the slope face(horizontally), and founded in medium dense or denser native soils or properly prepared structural fill. We recommend a minimum width for isolated and continuous wall footings to meet IBC 2006. Footings founded as described above can be designed using an allowable soil bearing capacity of 2,000 psf(pounds per square foot) for combined dead and long-term live loads in areas of medium dense to dense soils. The weight of the footing and any overlying backfill may be neglected. The allowable bearing value may be increased by one-third for transient loads such as those induced by seismic events or wind loads. Lateral loads may be resisted by friction on the bases of footings and floor slabs and as passive pressure on the sides of footings. We recommend that an allowable coefficient of friction of 0.40 be used to calculate friction between the concrete and the underlying soil. Active pressure may be determined using an allowable equivalent fluid density of 150 pcf(pounds per cubic foot). #07-0534 10011 Blomberg Street SW, Olympia,WA 98512 19 Phone#: (360) 754-4612 Fax#: (360)754-4848 GEOTECHNICAL TESTING LABORATORY We estimate that settlements of footings designed and constructed as recommended will be less than 1 inch, for the anticipated load conditions, with differential settlements between comparably loaded footings of '/s inch or less. Most of the settlements should occur essentially as loads are being applied. However, disturbance of the foundation subgrade during construction could result in larger settlements than predicted. RECOMMENDATIONS FOR FLOOR SLAB SUPPORT Slabs-on-grade should be supported on medium dense or dense native soils or on structural fill prepared as described in the "Structural Fill" section of this report. We recommend that floor slabs be directly underlain by a synthetic vapor barrier. Below the synthetic vapor barrier, we recommend a minimum 6-inch thickness of coarse sand and/or gravel containing less than 5 percent fines (by weight). The drainage material should be placed and compacted to an unyielding condition. A synthetic vapor barrier must be used for the control of moisture migration through the slab, particularly where adhesives are used to anchor carpet or tile to the slab. A thin layer of sand may be placed over the vapor barrier and immediately below the slab to protect the liner during steel and/or concrete placement. The lack of a vapor barrier could result in wet spots on the slab,particularly in storage areas. RECOMMENDATIONS FOR RETAINING WALLS Retaining walls may be utilized on the sloping portion.of the site to retain fill material. The lateral pressures acting on the subgrade and retaining walls will depend upon the nature and density of the soil behind the wall. It is also dependent upon the presence or absence of hydrostatic pressure. If the adjacent exterior wall space is backfilled with clean granular, well-drained soil (washed rock), the design active pressure may be determined using an active pressure coefficient equal to 0.25 (Ka = 0.25). This design value assumes a level backslope and drained conditions as described below. Retaining walls located on or near the toe of a slope that extends up behind the wall should be designed for a lateral pressure, which includes the surcharge effects of the steep slope in proximity to the wall. Although not expected at this site,the following data is provided for planning purposes. For an irregular or composite slope, the equivalent slope angle may be determined by extending a line upward from the toe of the wall at an angle of 1 to 1 (Horizontal to Vertical)to a point where the line intersects the ground surface. The surcharge effects may be modeled by increasing the equivalent fluid pressure for flat ground by the percentage given in the following table: SLOPE INCLINATION:EQUIVALENT FLUID PRESSURE Slope Angle Percent Increase Equivalent Fluid Pressure Horizontal 0% 35 pcf 3H:1V 25% 44 pcf 2H:1 V 50% 53 pcf 1H:1V 75% 61 pcf If the walls are greater than 4 feet in height, exclusive of the footing, additional design considerations should be applied. Walls greater than 4 feet in height must be designed by a Professional Engineer. #07-0534 10011 Blomberg Street SW,Olympia, WA 98512 20 Phone#: (360)7544612 Fax#: (360)754-4848 GEOTEC NICAL TESTING LABORATORY Positive drainage,which controls the development of hydrostatic pressure, can be accomplished by placing a zone of coarse sand and gravel behind the walls. The granular drainage material should contain less than 5 percent fines. The drainage zone should extend horizontally at least 18 inches from the back of the wall. The drainage zone should also extend from the base of the wall to within 1 foot of the top of the wall. The drainage zone should be compacted to approximately 90 percent of the MDD. Over compaction should be avoided as this can P PP Y lead to excessive lateral pressures. A perforated PVC pipe with a minimum diameter of 4 inches should be placed in the drainage zone along the base of the wall to direct accumulated water to an appropriate discharge location. We recommend that a non-woven geotextile filter fabric be placed between the drainage material and the remaining wall backfill to reduce silt migration into the drainage zone. The infiltration of silt into the drainage zone can,with time,reduce the permeability of the granular material. The filter fabric should be placed in such a way that it fully separates the drainage material and the backfill, and should be extended over the top of the drainage zone. Lateral loads may be resisted by friction on the bases of footings and as passive pressure on the sides of footings and the buried portions of the wall. We recommend that an allowable coefficient of friction of 0.40 be used to calculate friction between the concrete and the underlying soil. Mason County has provided a prescribed retaining wall design that may be used for non-bulkhead retaining walls less than 4 feet in height. i i 907-0534 10011 Blomberg Street SW, Olympia,WA 98512 21 Phone#: (360)754-4612 Fax#: (360)754-4848 GEOTECHNICAL TESTING LABORATORY MASON COUNTY PRESCRIBED WALL DESIGN MASON COUNTY DEPARTMENT OF COMMUNITY DEVELOPMENT Masm County Bfd$.Ill.426 West G-edar Street PO Box 180,Shelton,WA 9S584 wvM.00.nasan.see.uS (M)4274570 Belfair j275-4487 Eimat380)4821-52B4 UPLAND CONCRETE RETAINING WALL Pre,scriptive Design DESIGN STAWAROS 00 NOT APPLY TO SS[ORSLME EROSION CONTROL BULKHEADS T, I 5'IOpe less than cr equal to 1:1 J( r I 1 I FfiDIVIVE FLOCK, Ffr•�,ry C:.YiTiN, I t I I 1 I � �1't1YF61cgdroGK 1L Ij IiGFS A7 Ir'o.c, — •. j al F1�r OtIG I I I 1 I 1 I T�v2- L'• GF;+7JhD ^� &.RFhr_E ?11 ,,.N `t Pert—oad pipe wymgnted to an I 12'min. pr edloeMn. I I I t 1 I I 1 I I crane 5e enn �'I - I I ! 1 i I i 1 I -4- 1 1 • _y ' y. H 1 1 e i 1 I I 1 u 4 . 1 thADeSHE:,F.'Y.E+ t-8-6ARS nab Lt-'E 2v6 Edl K.r4()CK.rt,JT ELE AT10N B N{iTE SECTION 4+LCINr,;;F SS-134'S IS SFI�i:,TXIMATE I.,ISE T4,E!-IL4R FF i1KR T EWRS at,[,SPACE EVEri-Y W.' C'C(XVER 4 W e T srcttc�a0RAPa taacTta Euas rear trr Frua M me*r sim mr"a vtam" vzsmu agm "At** LtNcnt s aom LES PER iaffr 31-T 9 31E' 12' '-7 S 413 10 0.30 1,7 17 7W — 1rr a0' 3'-17 11 319' 17 13.1 7 50 10 0. 1i7 - atis — 1rr 7' 4'•9' 13 313' 1r 15.5 c 6-G 1- 0.37 Sc 9' 5'-a E'-7 s'3 5' 4al 15 3.9' 17 :tA i #07-0534 10011 Blomberg Street SW, Olympia, WA 98512 22 Phone#: (360) 754-4612 Fax#: (360)754-4848 GEOTECNICAL TESTING LABORATORY Prescriptive Concrete Retaining Wall Nvsighr:Maximum right fief Uplwd concrete retaining walls installed in accordance with the prescriptive design shown on the reverse side need not be designed by an engineer unless the Mason County Building Dept.determines special conditions exist. Any retaining wall exceeding eight feet in height or varying from the prescriptive design requires an engineered design. Locafion ofRetaining(Mall Retaining walls must only be placed against stable slopes, consisting of firm,,undisturbed soil. Drainage must be provided as shown with a 4'perforated drain pipe or 2`weep holes spaced not less than 12 feet on center. No surcharge load,such as a building or driveway,,may toe placed on the retaining wall or within a distance equal to the vertical height of the retaining wall unless an engineered design is prepared for the additional load. Ground Surfat-e Above Rultaining Wall The ground surface above the retaining waft shall be less than or equal to 1:1 (i_e_ 1-foot-Vertical to 1-foot horizontal), Rgtafning Wall Ftacemrsnt The top of the footing for the retaining wall must be set a minimum of 12 inches below grade. The 'ruing and wall dimensions shall not be less than outlined in the retaining wall chart. The footing shall be placed on firm,undisturbed earth. Drainage A minimum of 12 inches of washed granular drainage material shall be placed between the undisturbed soil and the retaining wall. The drainage materials must be c4xnposed of gravel with 1-inch particle sizes. Two-inch weep holes shall be located approximately 6-inches above grade,L—alow the granular drainage material, spaced not less than 12-feet on center. At the base of the wall. a perforated drain pipe,with at least a four-inch diameter,shall be installed within the drainage materials. The drain pipe must drain to a point of discharge,approved by Mason County. Inspections Prior to the placement of concrete,the buiider rivust schedule an inspection of the formwork and reinforcement placement for the retaining wall footing_ During the first inspection,the inspector will verify the soil condition.footing dimensions,footing reinforcement,and footing placernent as well as the provisions for drainage. At the nex� inspecfion,the inspector shall verity the wall dimensions and reinr-fcement prior to fhe wall pour. A final inspection must be performed once all work is complete. To schedule an inspection call time Mason County 24-hour recorded inspection request fine at(36D)427- 7262. Inspections can also be requested online at: or by fax.at(360)427-7790" 6trtien requestrng an mspect ron please provide>5?e fo#otwng tntormstron_ 1)Name on permit 2)type of inspection 3)Permit number 4)Site Address 5)Type of permit 6) Date inspection requested and 7)flame and phone number of caller. 407-0534 10011 Blomberg Street SW, Olympia, WA 98512 23 Phone 4: (360) 754-4612 Fax 4: (360) 754-4848 OTECHNICAL ` ESTtNG LABORATORY RECOMMENDATIONS FOR RETAINING WALL ALTERNATIVES Typically, block wall systems are more cost effective for long-term walls than the other options. Specific design criteria for these options can be provided at your request by the block manufacturers. RECOMMENDATIONS FOR SITE DRAINAGE All ground surfaces, pavements and sidewalks should be sloped away from the residence and associated structures. Surface water runoff should be controlled by a system of curbs, berms, drainage swales, and/or catch basins and tight-lined into the appropriate drainage facilities. We recommend that conventional roof drains be installed. We recommend footing drains shall be installed for the proposed structure. The roof drain should not be connected to the footing drain. For footing drains, the drain invert should be below the bottom of the footing. Typical drainage control measures are included on Figure 3. Onsite irrigation to lawn areas shall be closely monitored. We recommend additional testing occur at the proposed infiltration location. Either a double ring infiltrometer or a grain-size calculation will determine the permeability of the onsite material. SEPTIC IMPACT The existing septic drainfield is located in Existing Septic the central portion of the site. Chapter 246-272-09501 of the Washington Administrative Code requires a minimal horizontal separation between septic drainfields and various facilities. We conclude the slope stability of the site will not be adversely impacted by the proposed v structure and the existing septic drainfield will not adversely impact the proposed addition. See photo right. CONCLUSIONS AND RECOMMENDATIONS GENERAL Based on the results of our site reconnaissance, subsurface observations, and our experience in the area, it is our opinion that the site is suitable for the proposed project. The proposed building location is stable relative to deep- seated instability and will not be affected by the proposed structure. The proposed structure will not undermine adjacent slopes. Proper drainage control measures will reduce or eliminate the potential for erosion in this area and improve slope stability. The hazards of the landslide area can be overcome in such a manner as to prevent harm to property and public health and safety, and the project will cause no significant environmental impact for the life of the project. i #07-0534 10011 Blomberg Street SW, Olympia,WA 98512 24 Phone#: (360)754-4612 Fax#: (360)754-4848 GEOTECHNICAL TESTING LABORATORY If tested and confirmed, the onsite soils may suitable for use as structural fill material. Saturated soil conditions may be associated with these soils during or following extended periods of rainfall. However, to reduce grading time and construction costs,we recommend that earthwork be undertaken during favorable weather conditions. Conventional construction equipment may be utilized for work at the site. Conventional spread footings may be utilized at the site for support of the structure. We do recommend that roof and footing drains be installed for the structure with conventional spread footings. A vapor barrier is recommended for all slab-on-grades. Conventional spread and continuous wall footings appear to be the most suitable type of foundation for the support of the proposed structure. REPORT LEMTATIONS AND GUIDELINES FOR USE We have prepared this report for the exclusive use of Chad Clayton and his authorized agents for the proposed addition in Mason County, Washington. Site inspections, research, and mapping have culminated in this report. This report is intended to meet the requirements of the Mason County Critical Areas Ordinance. This report does not specify setbacks for: line-of-sight setbacks, FWHCA setbacks, eagle tree setbacks, wetland setbacks, or property line setbacks. Within the limitations of scope, schedule and budget, our services have been executed in accordance with generally accepted practices in the field of geotechnical engineering in this area at the time this report was prepared. No warranty or other conditions,expressed or implied, should be understood. CONTRACTORS ARE RESPONSIBLE FOR SITE SAFETY ON THEIR OWN CONSTRUCTION PROJECTS Our geotechnical recommendations are not intended to direct the contractor's procedures, methods, schedule or management of the work site. The contractor is solely responsible for job site safety and for managing construction operations to minimize risks to onsite personnel and to adjacent properties. READ THESE PROVISIONS CLOSELY Some clients, design professionals, and contractors may not recognize that the geoscience practices (geotechnical engineering or geology) are far less exact than other engineering and natural science disciplines. This lack of understanding can create unrealistic expectations that could lead to disappointments, claims and disputes. Geotechnical Testing Laboratory includes these explanatory"limitations"provisions in our reports to help reduce such risks. Please confer with Geotechnical Testing Laboratory if you are unclear how these"Report Limitations and Guidelines for Use"apply to your project or site. GEOTECHNICAL,GEOLOGIC,AND ENVIRONMENTAL REPORTS SHOULD NOT BE INTERCHANGED The equipment, techniques and personnel used to perform an environmental study differ significantly from those used to perform a geotechnical or geologic study and vice versa. For that reason, geotechnical engineering or geologic reporting does not usually relate any environmental findings, conclusions or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Similarly, environmental reports are not used to address geotechnical or geologic concerns regarding a specific project. I #07-0534 10011 Blomberg Street SW,Olympia,WA 98512 25 Phone#: (360)754-4612 Fax#: (360) 754-4848 GEOTEC HNICAL TESTING LABORATORY REFERENCES MAPS DeLorme 3-D TopoQuads(2002),Source Data USGS,Yarmouth,Maine. Dragovich,Logan, Walsh, and Schasse (2002), Geological Map of Washington-Northwest Quadrant(Geological Map GM- 50),published by Washington State Department of Natural Resources. Logan (2003), Geologic Map of the Shelton 1:100,000 Quadrangle, Washington, (Open file report 2003-15),by published by Washington State Department of Natural Resources. Noble and Molenaar (1970), Geologic Map of Southeastern Mason County, Washington, Water Supply Bulletin 29, Plate 1, Published by Washington State Department of Water Resources Palmer, Magsino, Poelstra, Bilderback, Folger, and Niggemann (September 2004), The Liquefaction Susceptibility Map of Mason County, Washington,published by Washington State Department of Natural Resources. Palmer, Magsino, Bilderback, Poelstra, Folger, and Niggemann (September 2004), The Site Class Map of Mason County, Washington,published by Washington State Department of Natural Resources. Rogers, A. M., Walsh, T. J., Kockelman, W. J., and Priest, G. R. (1996), Map showing known or suspected faults with quaternary displacement in the Pacific Northwest, published by U.S. Geological Survey OFR 91-441-0, Plate 1, scale 1:2,000,000. Smith, Carson (1977), Relative Slope Stability of the Southern Hood Canal Area, Washington,prepared in cooperation with the Washington Department of Natural Resources Division of Geology and Earth Resources; and, Department of the Interior United States Geological Survey. Dragovich,Logan, Walsh, and Schasse(2002), Geological Map of Washington-Northwest Quadrant(Geological Map GM- 50),published by Washington State Department of Natural Resources. i Walsh(1997), The Canyon River fault, an active fault in the southern Olympic Range, Washington: Washington Geology, v. 25,no.4,p.21-24,published by U.S.Geological Survey. Washington State Department of Ecology (1979), Coastal Zone Atlas of Washington, Volume 9, published by Washington State Department of Ecology. PUBLICATIONS Ambrose(1981),Simplified Design of Building Foundations,Table 2.5,pages 48-57,published by John Wiley&Sons,Inc. ASTM International(2005),Annual Book of Standards 2005, Section 4, Volume 4.08,published by ASTM International,West Conshohocken,Pennsylvania. Bloom(1991),Geomorphology,published by Prentice-Hall,Inc.,Upper Saddle River,New Jersey. Gallagher, Patricia M. (October 27, 2000), Passive Site Remediation for Mitigation of Liquefaction Risk, Dissertation submitted to the Faculty of the Virginia Polytechnic Institute and State University,Virginia. International Code Council,Inc.(2004),2003 International Building Code,published by International Code Council,Inc. #07-0534 10011 Blomberg Street SW,Olympia,WA 98512 26 Phone#: (360) 754-4612 Fax#: (360)754-4848 GEOT ECHWtA L T EST ING LABORATORY International Code Council,Inc.(2006),2006 International Building Code,published by International Code Council,Inc. Kollmorgen Instruments Corporation (1994), Munsell Soil Color Charts (1994 Revised Edition), published by Macbeth Division of Kollmorgen Instruments Corporation,New Windsor,New York. McCarthy(1993),Essentials of Soil Mechanics and Foundations,published by Prentice-Hall,Inc.,Upper Saddle River,New Jersey. Moffit(1992),Surveying 9`h Edition,published by Harper Collins,New York,New York. Ness,Fowler,Parvin(1960),The Soil Survey of Mason County, Washington, USDA Soil Conservation Service,in cooperation with the United States Department of Agriculture, and Washington Agricultural Experimental Station, and the Soils Conservation Service. Parks, Neal, Koloski, Laprade, Molinari, Butler, and Lorentson (November 2006), Guidelines for Preparing Engineering Geology Reports in Washington,published by Washington State Geologist Licensing Board,Olympia,Washington. I Prakash(1981),Soil Dynamics,Figure 6.3,page 173,published by McGraw-Hill,Inc. Sowers(1979),Introductory Soil Mechanics and Foundations: Geotechnical Engineering,Table 10:4,page 472,published by Macmillan Publishing Co.,Inc. Washington State Department of Transportation(WSDOT)(2005),Standard Specifications for Road, Bridge, and Municipal Construction 2006 M41-10,prepared by WSDOT Engineering Publications,P.O.Box 47408,Olympia,Washington. WEBsrrES Mason County Government Information Services (http://www.co.mason.wa.us) Mason County Codes,Ordinances,and Regulations (http://www.co.mason.wa.iis/code) Puget Sound Lidar Consortium (http://pugetsoundlidar.a ss.washington.edu/lidardata/index.html) Slope Stabilization Erosion Control Using Vegetation A Manual of Practice for Coastal Bluff (http://www.ecy.wa.gov/biblio/9330.html) Vegetation Management Guide for Puget Sound Bluff Property Owners (http://www.ecy.wa.gov/biblio/9331.htm1) United States Department of Agriculture Natural Resource Conservation Service (http://soildatamart.nres.usda.gov) Washington Administrative Code (http://apps.leg.wa.gov/wac/) Washington Department of Ecology (http://apps.ecy.wa.gov/welllog) (https://fortress.wa.gov/ecy/coastalatlas/viewer.htn) #07-0534 10011 Blomberg Street SW,Olympia,WA 98512 27 Phone#: (360) 754-4612 Fax#: (360)754-4848 I GEOT CHNICAL TESTING LABORATORY APPENDIX 407-0534 10011 Blomberg Street SW,Olympia,WA 98512 28 Phone#: (360)754-4612 Fax#: (360) 7544848 i ~1 • �� -ter �-�. Y r �4 Pile� - .� • # 1 � 1 �• GEOTECHNICAL TESTING LABORATORY I LABORATORY RESULTS U.S.Standard Sieve Opening in Inches U.S.Standard Sieve Numbers Hydrometer Results 100% 20 6 4 3 11A % % ? #4 10 16 20 30 40 50 100 200 0% 90% t `. 10% 80% v 20% r 70% ` 30% 2) 60% `.. 40% T m 50% ` 50% c ` @ 40% ` 60% 0 a- 30% ` 70% 20% . `` 80% 8-1 10% • - 90% 0% 100% 1000 100 10 1 0.1 0.01 0.001 Grain Size in Millimeters Gravels Sands Cobbles Silts Clays Coarse Fine Coarse Medium Fine Date: 09/14/07 D10= 0.22 Classification %Gravel Sample#: 1336 D30= 1.34 SW,Well-graded Sand with Gravel 43.16% Sample ID: Sand with Gravel D60= 5.40 Specifications %Sand Source: B-1 Cc= 1.52 WSDOT 9-03.10 Gravel Base 52.35% Project: Clayton,Chad Cu-24.87 %Moisture: 7.3% %Silt&Clay Client: Clayton,Chad Liquid Limit--0.00 Dust Ratio= 4.49% Boring#: C-33 Plastic Limit--0.00 Fineness Modulus Sample Meets Specs Depth: 5' Plasticity Index--0.00 4.63 Yes oarse Actual Interpolatedroes Actual Interpolated Section Cumulative Cumulative Section Cumulative Cumulative Sieve Size Percent Percent pecs Specs Sieve Size Percent Percent pets Specs US Metric Passing Passing I Max Min US Metric Passing Passing I Max Min 6.00" 150.00 100.0% #4 4.750 56.8% 56.8% 100.0% 22.0% 4.00" 100.00 100.0% #8 2.360 42.5% 42.5% 3.00" 75.00 100.0% #10 2.000 38.1% 2.50" 63.00 100.0% #16 1.180 28.1% 28.1% 2.00" 50.00 100.0% 100.0% 75.0% #20 0.850 22.2% 1.75" 45.00 100.0% #30 0.600 17.7% 17.7% 1.50" 37.50 100.0% #40 0.425 14.9% 1.25" 31.50 100.0% #50 0.300 12.9% 12.9% 1.00" 25.00 100.0% 100.0% #60 0.250 11.1% 7/8" 22.40 96.1% #80 0.180 8.7% 3/4" 19.00 90.90/0 90.9% #100 0.150 7.7% 7.7% 5/8" 16.00 88.4% #140 0.106 5.8% 1/2" 12.50 85.5% 85.5% #170 0.090 5.1% 3/8" 9.50 79.9% 79.9% #200 0.075 4.5% 4.5% 10.0% 0.0% 1/4" 6.30 64.4% #270 0.053 Copyright Spears Engineering&Technical SwI'm PS,19962004 #07-0534 10011 Blomberg Street SW, Olympia,WA 98512 30 Phone#: (360)754-4612 Fax#: (360)754-4848 GEOTECHNICAL TESTING LABORATORY U.S.Standard Sieve Opening in Inches U.S.Standard Sieve Numbers Hydrometer Results 100% 20 6 4 3 1% % % ? #4 10 16 2030 40 50 100 200 0% 90% ` . 10% 80% -- `. . . 20% • 70% �. ` 30% � L 60% ` . �.` . . 40% c 50% ` 50% T .n d40% �.` .... 60% ID 30% Elf 70% 20% ~. �...` ♦ 80% 10% _ _.. ...�.. _ 90% 0% 100% 1000 100 10 1 0.1 0.01 0.001 Grain Size in Millimeters Gravels Sands Cobbles Silts Clays Coarse Fine Coarse I Medium Fine Date: 09/14/07 D10=4.02 Classification %Gravel Sample#: 1337 D30= 12.08 GW,Well-graded Gravel 89.17% Sample ID: Gravel D6o= 18.41 Specifications %Sand Source: B-1 Cc= 1.97 WSDOT 9-03.10 Gravel Base 9.34% Project: Clayton,Chad Cu=4.58 %Moisture:3.5% %Silt&Clay Client: Clayton,Chad Liquid Limit-- 0.00 Dust Ratio= 1.50% Boring#: C-33 Plastic Limit-- 0.00 Fineness Modulus Sample Meets Specs Depth: 12' Plasticity Index-- 0.00 6.91 No Coarse Actual Interpolatedroes Actual Interpolated Section Cumulative Cumulative Section Cumulative Cumulative Sieve Size Percent Percent Specs Specs Sieve Size Percent Percent Specs Specs US Metric Passing Passing Max Min US Metric Passing Passing Max Min 6.00" 150.00 100.0% #4 4.750 10.8% 10.8% 100.0% 22.0% 4.00" 100.00 100.0% #8 2.360 8.1% 8.1% 3.00" 75.00 100.0% #10 2.000 7.6% 2.50" 63.00 100.0% #16 1.180 6.5% 6.5% 2.00" 50.00 100.0% 100.0% 100.0% 75.0% #20 0.850 5.9% 1.75" 45.00 96.1% #30 0.600 5.4% 5.4% 1.50" 37.50 90.3% 90.3% #40 0.425 4.5% 1.25" 31.50 88.9% 88.9% #50 0.300 3.9% 3.9% 1.00" 25.00 77.8% 77.8% #60 0.250 3.5% 7/8" 22.40 71.3% #80 0.180 2.9% 3/4" 19.00 62.8% 62.8% #100 0.150 2.6% 2.6% 5/8" 16.00 48.5% #140 0.106 1.9% 1/2" 12.50 31.9% 31.9% #170 0.090 1.7% 3/8" 9.50 18.3% 18.3% #200 0.075 1.5% 1.5% 10.0% 0.0% 1/4" 6.30 13.3% #270 0.053 Copyright Spears Engi,=ring&Technical Services PS,19962004 07-0534 10011 Blomberg Street SW, Olympia,WA 98512 31 Phone#: (360)754-4612 Fax#: (360) 754-4848 GEOTEC NICAL TESTING LABORATORY SHEAR RESULTS Peak Shear Stress vs. Normal Stress 2500 2000 38° w a N 1500 M d U)N 1000 Y M d ��l/4 ton500 l2 ton ton Cohesion = 200 psf 0 0 500 1000 1500 2000 2500 Normal Stress (psf) II #07-0534 10011 Blomberg Street SW, Olympia, WA 98512 32 Phone#: (360) 754-4612 Fax#: (360) 754-4848 GEOT CHNICAL TESTING LABORATORY WELL LOGS JOW rki 0Aihia fRtl F*M cbPy war Pso Card qa `7+5 ilan D"Wiir atinili'Yy WATER WELL REPORT 3iriani Cgri-Ocxx'■Ciyy � 1Riro Ci�lRi-�+i+i.ra Ceoi STATE CF WASH NQTON wiii:�prfmh iiu�_ tly OWNL�i Faaa - _ +`t Mi■rrra ii72� M LOCATION OF WELL: crrair P9 dais _� w ,< t •n waa. M* 9"Iry ADVORIN OF WELL tw aiiR"is3wv4_ �d) PiiCFbsED iI�SL� f�ikh wiYu I�riit Mii 71 ' MNI 0 110) 1IW L LW or ABANDtiNMEWT Mf 9DUM OCWWMON bNVsiir TwltiYfli CJ othaw ❑ Pr}tfiMlriill D#j&%M big 60&.crrvaclii•Hai ei ---?I nail iaFfriahsi..old 0110-_ _.. ---- ihldYciii d iOiiNiPa fild lihi ikd ind ni►R d iRi olhiirifl K Kr/n ebilaal pi::uriy �A'I TYpE CF wbhxs+c`+riiiawowcrww .ft tot".eta:::wYiwvkh,§rwoeffin mown, awwe itteranap-- -. _- - +1erriweaiM R q+wn ;! Mserail: O 8arsd © aiA7■nW PRf6ii 6hMpwifd dilsla Q DAvW G r+iiaa.riEi;ai..e G ivasi,y J~ O GA.+fLeff �A i A a/-- t$? DIIilE�151dpS�i'}q�;i:ii-n.r,nisw+ ,,3 i.chrw ', '' Dni►iiil..a�i�..'�..iii;. �fl bi etwi�irbrd■rill � t�r R. ---- — �- -- riaiiae 6L'xr,+riM ti.le It. 'YiPiGaiel 6ia7n.iP0�+ M,lD i6 6ei ipMRiMrtl Va■ IiR -------.+ 9+ffVINilms eaw i1.re n. i -- Asnimrllaa■bum—n.ib R. _ i�sM1p'MIsR■Yam ii.is .�.�ft, uftaiiit: Vit. iio Tp}i YiiW fii Dowi Si6i iiira._..- _ __ 1.it ff• Oii-c-_._-----. am Has ii Otnral;ialta '*xj qa sis■av- 8iOMA D"k Yii v ❑ IiMt lgiMf7 i. '� Matinirsip Mnrrl_-- SR.+■'•" ,._.....».» _ — — !}��1 J Old af/■hiir eeaia.ti rrriuiiiw�ii■13 Yr■U R1G .._. TY3i ar wii71_._. Giprhal iR11� _--. kifiiv%Of KIirQ Plriti CiF --- - _ i (7) PUMP lips: I M.P t i (b) WATER SPIN Lana.xi■e.w. s siaoe i:w ILbaiehi 00 at mar QiK. - ArtiriinDraRwri Ms.Wr- F,A& died _ '. AfiehNei':acrr if[yaWliid'bT .. "�•rjR.' .rr � --•••_'--_— � ID} iiYEEL TESTS; Or■ w.m�lr.eari.wt�+au«reaie�n.xciwii wartuirwi ! Wara.Ru Nir irRdi9 Vra Fbr.J ■y..�bi r+hart4 T* 'lam -. .._. WELL CONSTRUCTOR CEpTIFIGtT110r1: Ylfw- —pal,taihi alfh —.__k llrari�bnA ►ii. .-.._ .. .. . _. .. . ._.� I CCnalifh:iM aedror eor740 responsibility for taiairurllioe of tfrlr itlra, -_- fill Jif cperpWRp with PY WaSN0,teq wN Cmiib 1*R florldsedi. INaiariYi abed and the wllorm■lioh ripovifd aJbaYe are true ip CRY host Fics+..i•dN■.ChnR ictRn ar axro Wiaa Pr"P irnrd irfl I.�itwiRr■irwRRrRtl inaliNtlpr etha OMiM. tramwailioaia.aear4'nr0 y (/ Twr wrArlr•M t— M.rwW v HAM E ---- - -- .,. FF930k Ff%L OR CONPORAIR d rrnr On ffwr' 0".�01�l.i•r� lNi "' fSlpned) CiCaruraa fLo7 wiR.riih e.ar.d,.r.■n.. irfs r�nicr■iaem Coairapar'e t4rt■ei sr.tea...riu■t>RM iia M rt.for _ hrf RipirifM 4rra.iripr _ vparh. 17aos I�� Mo, T!'lf��NlSY Dale rQ _ rNMeira,"9,wwa.'—writ■eronkso aniihr:.r»-di! v"o 4.1 1 #07-0534 10011 Blomberg Street SW, Olympia,WA 98512 33 Phone #: (360) 754-4612 Fax#: (360) 754-4848 GEOT CHNICAL TESTING LABORATORY #li.arlalscl aed■tent t"oi>3 wtEh �WATT, ApplitaUon Na. T, 1j4'�I.L �Ci�'I' -- . ivti�iLi tlrHtrr�Cop] VrAft OF WASE W fteiwt No. .. (I) C#'@' &MM. tvami u i1 )Ul ma 32t114-.225Lli...AVjL99 Kentjv-1U ..()9 1c2. _.._...... (2) LOCATION ON WIMLs ._..... .._..._...._..._.. .— t2atr)% and dto% iin in teruw ar ri"vis wi mrffrr Ut 29 P1 n f t. A (3) PROP0510 USIL fYs maw M 7e4w G atinkipd 11 (Yid WEl.If �t is t7ri vhM 0 'ftw Welt 0 Oibw U Atis;taa_ tor,eitoi�tfi7 r*ii o1 islatarial sq#atn:eWri,and a it OT Wi is a tki kiwll rntl%alit-*sf Ow va"vrW In*Vvh - -- -- - 7[rGtMrR Otni+��- a if krCei ar%i i�r+V f�a:aisl4 efw+i4a eJ p?rivaita%. Itf mw txaa Gael.... . isi�rw,t:t i'>its>K To How t'iitl M 9feUd'111.4 __— ber"" C] 15td,le & i5rl.ae ltaandltlaeyd Amara 3stisd C) ica� OCA!< tYidil��: Ulaaretmef will _C.224 482 t fsruli9 {B} CONSTRUCTION YfiEtAll i ceff txirm nand aril gLffit+ol., wat 2 .r . 26 L)aft i ttlt]kda....b. ..pian.tn=._0,___ n.m 4£s2 it, pll-ritn9 �.? 23 Inra&dvd Dtata,uom ..- ft.to ..._......_3t. - wradea is auras.from.._..... n, nT Z" Pbrffiritil)Stut Yet p VdXZ - Y'ppe of pirfaraior used........... ;ti brg1m clay_A ,F7•-vravEA �- )iiiL yerior4ac fli irate..._, -_it.to ._.......-.. 3t, �25 ....__.-.._.ft. Hsl=3twan to J .psc3oratltifi fiGtt_ .!R --- clay with gravel, —32-5-- 340 �CYtilB3: Sroi�i ilfi p i''' staffs? � - -- 1]tird _Saki die .. _!exit_si.�� 31 ss .il. Q �� MOM, ___..Slot alai ...___ercori -.._..s1f.to.__._...JL G rawd pdLked' Yea 13 Na &iae of SnTet: - vei Gn. pisiatl fraA R to Bue&" sw'. yes Ex bfu O To whas depiht SQ...-. [t C'++�"' �'--� srrl raa f at• �__ � 1 482- _�.---- Dii Say Fria eerttain untijs?ita water? Yasa MIX] i typo of watatr_... ....... DepLh of arala �.-_..- Naaha4 .........._. ._......_.___ (7) POW. utautuuie.r'a taeae W9bttD1 .._ .... __- Typr: .Stfbtebe>:5�.b1�._.... _.-T--- ($) WATEU LEVEL s: iaan.surese►rlaysulen st+eMa mean faa lerel. .. ._..__._.....,.n• _.-,. ._.! _..--...-....,.^.-- .__..__. Statbe twit __.4!��r�. .... ..._.n.bk.too of*vu D.ie...._._..___....__. Artesian priaaerG ._. .. ..tht. per adUSEt inch krUsian wile1 if eoeirolted ar.. ._._.._...----.-... ....._..._..._ .t Drardawe is ahio **I*?amt ite?lat•s1 a (Q} WELL TESTS; 1owe.w oeww etas?[lava rrar�at�t+a.-----...__....._,..._is-.._. co,"WAJ--Deracter Wag a ilumP it3i M3401 Yes❑ Korf if yss,by wkiam? _.... Y1rla: al.Jmm.wntn _ is fi. erawdawn lase 1 _�s WELL DRILLERS STATEMENT: Thin md1 wss driUad under my lurt;sdiction and ibis report is — - - true to the best of my,knowiedei and belief_ &a,csJrery Sato IL)nis taken >K sate when irronP tUr"d 01<) garter lint rteuuree train.au wp w water Ierrl) NAM. �},l�Y Tune *Q'wi Ivst Tme watop Level I fim, tYa tar Giuer Itaenie.arm.or corpatntion) (Type or priM) ........ _.... ............................... .._.................._ M I.............. . ............_..._ — Date at __.. {v� .. . ue 8at sGSL Q........LN/mIm.vn L.. .L ...it-srGwdo n awr-_---- .._..1ri. fWon'XW. rt ft7tE•len 3os'.._•"-----......._.._ •,..._p.pm. Dais...._...........----- ___.-_._. ly T Temperature at water.._ Wfa a Cham)rd ara&WW mode?Ya Nob@! I.LCtDaG N0..........�!�.�.{................ ...I}itI GBD �--......_.,1D.�.. 907-0534 10011 Blomberg Street SW, Olympia,WA 98512 34 Phone#: (360) 754-4612 Fax#: (360) 754-4848 GEOTECHNICAL 'VESTING LABORATORY - �W�{A.TER WELL REPORT y�■�y�p�� 11l�l1'1!!nl Of4wa1+��... Ci�1��00�1'�aP1311�.5~Cb�j—Qi'�jf C Miif.J €Caas#P;koc�lawDeem01SAN(Jt"rA ttrche) Modae of tw1w No.k$. caubvedou Daruwrissiaift ONGIN t.MSTA LOTION wwa Rol pwnif No. rr,Wke qrlMw Member WaSM lilfr4 08EG Lf60C 19 D maa t 0 leducids] 0 Pm"Owner Nx=BIJI I.&SHAWA IZER O.rmwma 0. 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BROWN&AND i3MVEL WATER 05 120 SLrtrsrr swh®Yw D w To Riu death?2R 5'P.LL SEAMS 8F&AND GRAVEL -. 95 UO blaai b rtaei{a deli RENTONtl1 - is ii6 i2G D�tlttajsops now uvaskoo*ta4 L7 Y. ❑.k4c i�e'btwst;i�t -17gD�adsb�ts_ udcl d ar eeclms is sa a8 AtRt4:x�.iibdrioa'f?to3d - - WAYE#e Y at►EIS Lauri aaieoetla+leldd■Dove teeny 6a k ie! R Sociefetxf bdk+v> N+lR Degs7 f .r,dsP- Ihr.w sgwd i*;b Rleoaae wale p aspalhdDy MP.valve.ekr.) w U,L TUTM Dnu*wu is emaum wsw Ia ei n lovmm b6m mw inei of u a pm w lat msdedl 0 Yee [] No if)M by whoa? 9FieGl:,_,�„pllmid.oilb�•_0.As,�crwn der.��,_Ys. y�: Y*WA: _gatlmfd.wdr 4 .R dhuriw,v Aw_hm. a AWWWrjdld!00W arbrrve a l AWV Puerg(urlorrd,,9 01-d-6!d.rw=vndfivw well t n?w wioierkwrQ tv Tier Rrcty[w.sl rum Wata I.a»I Ttne 1 dw Lard y _ 7 G Q!6 orkrt 6edla ter�Q pihom.v!$1a..b ,sfidt it•* � .•• - Ailerat p[,5ow.ith saa na St A,enmsIbw gp.m.Dea $CiitDale C= Letad Deft ti D7 T urf.Ysceq,�_wse.srbsrscetratjxtaaraeal ta. No T3_YPWUJ' N0:3233S759WQ 1�tt,t�otvsrxucr�xvc©tnFsc.4nor�:-I omLmvaaa amp!t�paruabdliRy fin GCOWMSMWaftv 01,and is VMW W r oe WMft M WWhiel(nota tern wnctnit—sbred+a& ht -Wa s-Rd wd Bee difOttd8t60d1 rtpOAGd At*n me rx W my bat Im"ivOw and b0cf. ©.IltiltEr b Eagiaoar g-naiiw D ifier ra>relet,e_Lkcm No.277DT DdIEnq Cam y NIt:H W)4 DRI114+At7 INC Nainc esr It,RE)-SAM3''LE N06 — Addvw M 9GX 123 i DriAalE;ik - taare S i j _ — -• _ -.- _ Ckf,SSt",&PUICT ORCHARD, WA,"366 EF TRAIN£ "Urdia's Lwow N,s OS 0 Mi Vlll.£Y Dri Gaouecux S ReBicpretirxe Nl�NCi00O113Ti1M/ Date 1 .Wf�147 #07-0534 10011 Blomberg Street SW, Olympia, WA 98512 35 Phone 4: (360) 754-4612 Fax#: (360) 754-4848 �Tgogm �. Sm Is � � t o f�1 •DELORME DATU,,i OR THE SITE PLAN INCORPORATED + ,,..�••`` VARIOUS TECHNIQUES AND SOURCES --^--- Geotechnical INCLUDWG THE FOLLOW WO: TAPINGAND CILMOFACING.MIR,PE MOLES mwN v[uw%'M`r BEAN USING A BTER ANGLES AND lam/• I SIM WGSUSNJOABRUMONAOEOTRANSIT, / Testing SITE LOCATOPO VSWOA OARMW®HANDHELD GPS SON TOPOORAPHH:MAPS FROM DURVEYS® r'•� MASON COUNTY O.I.S.ON CO E,AND SURVEYS •! Laboratory RECORDED AT THE MASON COVNTY ASSESSOR GEOLOGIC SITE RECONNAISSANCE OCCURRED ON SEPTEMBER 14.I BY LEVINE. / ,/� +� THE SITE IS SHORT PLATTED AS LOT A OF SP N"T. ,J /!r •%•I // j� '" aR[eLaa i• mmrou r°[r[ wn.[uwnararw Eve 0-4, ;� %s[oP1-----"' n, Geotechnical Services E STNG QA/QC Services Testing Services PROPOSED•'•_•— runts°"ibrxlrur°M r°er. N $ a%!L°E °S AODIT M,(fa'x. ![au[awr°Mwro°w wonwaaq"w •%l E%ISTMO "4• 3. our o w.n..wau 10011 Blomberg St.SW R68CENCE ` le%r ME wo-e[anniu°neWorom.roarnmr.win["wyiw[w — 1 -- Olympia,WA 98512 Phow(360)7U4612 Fax:(3110)764-4048 / - f/ •"pwr�°^fww` ,W� Date:062E2007 w„a=U. Designed by:LEVINE ..^• ___ I/1rIM[1 rori[nNu°,°r„[e,nnw nnr. DmPn by:LEVINE """FOTEN°110.R1fe°"" Checked by:LEVINE % °aen Mw[ew[„.wm,re„ce wa e[eu.wnwwwRx •f-wRMr.nnr.a,F�f ar..u°ww.e°°w!°nvmM DwBa:09-28-07-09E rwnwm"LL oran r[vnlCw w Now wl![[r!!v!a°. PROJECT NAME: CLAYTON SITE 501 E.TIMBER TIDES DRIVE UNION WASHINGTON `•. PARCEL322367690281 11F RevisillK �w SCALE: i" = 200 FEET `\•__—//' ,'"[°.""`""."° °"'"°" 0 50 100 200 C.I.•11Y SCALE:INM=1001M w%tlall rots na! Ml FIGURE 2 SITE PLAN 1/2 INCH MINIMUM DIAMETER STEEL ROD (STRAP)CLAMPED SECURELY TO PIPE ;_� . CORRUGATED TIGHTLINE 4 INCH 'Al /4� MINIMUM,6 INCH SUGGESTED •,K.�ti�i•r•i c• �� y �-�1� .tit�.:::,1:^.. ,.' �Mf.•ir. T•i..:•.`tip.�'�:t:.:.-u•%r_ .:-. i w�-?'� :r`!...:r�- '''':'+'.::mot;•a'. 10 •.x,~'c?C '7�r �1 - ,..: :C,,•�"c_•....•. c-. ,:'„4`w: i`c. <, TIGHTLINE ANCHORED WITH TWO, 3 FOOT REBAR LENGTHS OR BOLTS. FLARE END SECTION QUARRY SPALL 7.t OR ENERGY -:' �``'='''; • ...:::;',;< _: ar;;: DISPERSION DEVICE :`<- �, :• '?=: ., }w :a::�z• ;: >::_:>.' j GRASS-LINED SWALE SHOULD BE A MINIMUM ONE FOOT WIDE AT THE BOTTOM AND ONE FOOT DEEP WITH A MAXIMUM SLOPE OF 5 PERCENT. MINIMUM 4 FEET LEVEL SECTION GEOTEXTILE FABRIC Geotechnical Testing Laboratory Geotechnical Services toot 1 Blomberg s.sW Olympia,WA 98512 FIGURE 3 Qfi/Q�Services Olympia, (360)754-4612 Testing Services Fu(360)754-4848 Not to scale DRAINAGE DETAILS 1 Geotechnical Testing Laboratory CROSS-SECTION A (SOUTH-NORTH) Geotechnical Services QA/QC Services Testing Services 10011 Blomberg St.SW Olympia,WA 98512 Phom:(360)754-4612 Fax:(360)754-4848 Data:092&2007 Deeig ed by:LEVINE Drewa by:LEVINE Checked by:LEVINE 230 LANDSLIDE Dwgf:09-2e-07-096 -HAZARD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . : . . . . . . . . . . . . . . . � 220 AREA ATED. . . . . . . . . . . . . . . . . . . BUILDING. . . �. . . . . . . . .� . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 GRAVELLY SAND SETBACK 0 2105FEET . . . . . . . . . . . . . .i. :. . . . . . . . . . . . . . : . .W. . . . . . . . . . . . 1 100%SLOPE 3%SLOPE P D W t €I€ 200 ........... .SEEP.................:... 5..I.I..DI.N. ............'..............................LANDSLIDE................0..................._................ I ................... ...... EXIS71fJ�. L CATIO � HAZARD F— ... . .. . . ._. . . .._.. . .,._. 190 DRAINFIELD BORING 1 AREA ! : VEGETATED W W 1 PROJECT NAME: GRAVE Y SAND FIL m 0 CLAYTON SITE 180 . . . . . . . . . . . . : . � . . . . . . . . . . . . . ; 7 • LLY SAND • . • " " " " " " " ' ' ' 501 E.TIMBER TIDES DRIVE 17O SAND RAVEL 809 LOPE F- I I UNION,WASHINGTON . . . . . . . . . . . : .7. . . . . . . . .� . . . . . . . .?. . . . . . �. . . SANDY GRAVEL... . . .IL . . . . . . . . L. . . . . . . . . . . . . + PARCEL 322357590281 ATED 160 i. . 3. . i ReMgnx 150 0 50 •100 150 " 1200 250 1300 SCALE:1 Inch:301eet FIGURE 4 CROSS-SECTION Ryan Crater- Re permit 1 From: Ryan Crater To: Clayton, chad Date: 7/15/2008 9:21 am Subject: Re: permit On or around November 7, 2007 you contracted with Geotechnical Testing Laboratory (GTL) to have them complete a geo-report for your property located at 501 Timber Tides Drive. Curtis Cushman is an Engineer that works for GTL and was in contact with Russell LaForce's the reviewer for the County. Contact Curtis Cushman @ ccushman@geotechnicaltestingl and see if he responded to Russell LaForce's questions from the e-mails dated 3/3/07 and 3/4/07. Below are the outstanding issues that need to be addressed by GTL. 1. A short history of landslide activity in the area is needed. 2. No landslide hazard area buffers were shown or mentioned. Please include or explain why no buffer is needed. 3. What is meant by collected grab sample? Does it mean the grab sample was from different depths? 4. The cross-section shows gravelly sand over sandy gravel, but the boring shows SW with gravel over GW. Can you resolve this? 5. The seep area was mentioned in the report, but not modeled in the stability analysis. 6. The stability analysis should also include modeling upslope of the addition. 7. The site plan scale mentions the scale is 1 inch to 200 feet, but the site itself appears to be 1 inch = 100 feet. 8. A note should be added to the site plan that soil erosion and control plan is needed. 9. Could you recheck the cohesion values used for the lower soil unit as the soil units in the stability analysis do not exactly agree with the ones from the boring? Regards, Ryan Crater Land Use Planner/Code Enforcement Mason County Department of Community Development 411 North 5th PO BOX 279 Shelton,WA 98584 Phone# 360-427-9670 ext. 577 Fax#360-427-8425 >>> chad clayton <galonclaytonCalhotmail.com> 7/14/2008 11:18 am >>> Ryan Crater- Re. permit 2� Dear Sir, Involving case# BLD2007-0143, I have submitted the necessary requirements, but according to your letter there are some remaining issues with the special report. You tell me to contact my consultant to see if Curtis Cushman has addressed Russell LaForces questions. I do not know who you are talking about. 1.)who is my consultant 2.)who is Curtis Cushman 3.)who is Russell LaForce? Thanks, Chad Need to know now?Get instant answers with Windows Live Messenger. http://www.windowslive.com/messenger/connect your way.html?ocid=TXT TAGLM WL messenger 072008 ICI �I PEON cot, MASON COUNTY Shelton (360) 427-9670 DEPARTMENT OF COMMUNITY DEVELOPMENT Belfair (360) 275-4467 Planning Mason County Bldg.1 411 N.5th Elma (360) 482-5269 P.O.Box 279 Shelton,WA 98584 �Bsf February 23,2010 TO BE KEPT IN T H rE Chad Clayton �' I ( !L 501 E Timber Tides ; t `v�-L Union,WA 98592 RE:Parcel No.32235-75-90291,Proposed access driveway to exempt storage buildings Dear Mr.Clayton: Staff met with you on February 16,2010 and we discussed your current proposal which is to install an access driveway to an area where you are proposing to build a couple of exempt storage buildings.This project is proposed on the above parcel which is adjacent to 501 E Timber Tides Road where an addition was proposed in 2007.The driveway and storage buildings are located approximately 90'from the addition that was proposed in 2007 of which a Geotechnical Report was prepared.No additional grading other than the driveway is proposed at this time and no structures requiring permits will be built.Therefore no Mason County permits are required at this time. The Geotechnical Report(done for parcel no.32235-75-90281)that was prepared by Lance Levine of Geotechnical Testing Laboratory and dated Nov 7,2007 has been reviewed for the current proposal for consistencies with the Mason County Resource Ordinance Landslide Hazard Area requirements.Because the current proposal is located in the same area as the original report area,staff has determined that the original geotechnical report can be accepted for this current project.This approval is granted with the condition that all of the Erosion,Drainage and Sediment Control recommendations that were proposed in the Report are followed throughout the development of the driveway through this adjacent lot. This current project may be accomplished without additional County permits or Geotechnical review at this time.Please keep in mind that even though the storage structures may be exempt from permits,they still need to meet the minimum setback requirements of 20'from side property lines and 25'from road easements or right-of-ways.Enclosed is a copy of your 2007 Geotechnical Report prepared by Geotechnical Testing Laboratory. If the driveway is to access the site off a County road,an Access permit will be required from the Mason County Public Works Department.Please call them at 427-9670,ext 450 for the application form. If additional grading or structures are proposed at a future date,please submit the proposal so that it can be reviewed for the need for additional review by the Planning,Building and Environmental Health Departments.I will make a note under your parcel number in our permit system that you have submitted the driveway project at this time and what we have determined should any questions arise.Thank you. Sincerely, Grace Miller,Planner DEPT OF COMMUNITY DEVELOPMENT V e c t o r E N G I N E E R I M 6\N C 309 WASHINGTON STREET NE OLYMPIA WA 98501 TEL:360 352-2477• FAX: 360 352-0179 R F i E D www.vechmenginftiingim.com D D C 0 3 2008 Mr.Robert D.Fink,AICP MSON GU.h't.F KING NUT. Mason County—Department of Community Development Mason County Bldg 1 P.O.Box 279 Shelton,WA 98584 Subject: Geotechnical Report Return Permit#:BLD 2007-01434 Parcel No.322-357-590-281 501 Timber Tides Drive Applicant:Chad Clayton Planner: Ryan Crater VEI#: 8001-009 Dear Mr.Fink, Enclosed you will find 2 geotechnical reports and related correspondence as requested on December 1,2008. Thank you for allowing us to work with you on this project. Should you have any questions, please don't hesitate to call. Sincerely, Russell W. La Force, P.E. Design Engineer Enc. I X:\8000 Files\8001 Mason County Geotech Reviews\8001-009 Mason_Co(Clayton)GR\Communication\Transmittal Letters\trans letter 12 02 2008 BLD 2007-01434.doc