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HomeMy WebLinkAboutGEO2013-00018 - GEO Geological Review - 5/10/2013 Pq Mason County Department of Community Develo ment Submittal Checklist For a Geotechnical Report Instructions: This checklist must be submitted with a Geotechnical Report and completed, signed, and stamped by the licensed professional(s) who prepared the Geotechnical Report for,review by Mason County pursuant to the Mason County Resource Ordinance. If an item found to be not applicable, the report should explain the basis for the conclusion. Applicant/Owner Mark Fenton Parcel# 4208-14-90042 &42908-14-90043 Site Address W Dayton Trails Drive, Shelton-WA 98584 (1) (a)A discussion of general geologic conditions in the vicinity of the proposed development, Located on page(s) Pages 1-3 (b) A discussion of specific soil types Located on page(s) Pages 2-3,4&5 (c) A discussion of ground water conditions Located on page(s) Page 4 (d) A discussion of the upslope geomorphology Located on page(s) Page 1 (e) A discussion of the location of upland waterbodies an (wetlands Located on page(s) Page 3 (f) A discussion of history of landslide activity in the activity in the vicinity, as availab a in the referenced maps and records Located on page(s) Page 3 (2) A site plan which identifies the important development and geologic features. Located on Map(s) Geo-Rpt Plan Sheets 1 & 2 (3) Locations and logs of exploratory holes or probes. Located on Map(s) Geo-Rat Plan Sheet 2 (4) The area of the proposed development, the boundaries of the hazard, and associateci buffers and setbacks shall be delineated (top, both sides, and toe) on 0 geologic map of the site. Located on Map(s) Geo-Rpt Plan Sheets 1 &2 (5) A minimum of one cross section at a scale which adequately depicts the subsurface profile, and which incorporates the details of proposed grade changes. Located on Map(s) Plan Shts 3&4 and GALENA Stability Analysis vgs 1 &3 of each analysis. (6) A description and results of slope stability analyses performed for both static and seismic loading conditions. Analysis should examine worst case failures. The analysis should include the Simplified Bishop's Method of Circles. The minimum static safety factor is 1.5, the minimum seismic safety factor is 1.1. and the quasi-static analysis coefficients should be a value of 0.15. Located on page(s) P2 4 GALENA Stability Analysis P intout vages 2& 4 of each prcl analysis. (7) (a)Appropriate restrictions on placement of drainage features Located on page(s) Pages 4- 5 (b) Appropriate restrictions on placement of septic drain fields Located on page(s) Page 2 (c) Appropriate restrictions on placement of compacted fills and footings PLANS MUST BE Located on page(s) Page 5 THEE d'03 TE _? ; PF dI Pa,. 1 of 2 Form Effective June 008 Discaimer: Mason County does not certify the quality of the work done in this Geotechnical Report. (d) Recommended buffers from the landslide hazard areas shoreline bluffs and the t ps of other slopes on the property. Located on page(s) Page 4 (e) Recommended setbacks from the landslide hazard areas shoreline bluffs and the tops of other slopes on the property. Located on page(s) Page 4 (8) Recommendations for the preparation of a detailed clearing and grading plan which s ecifically identifies vegetation to be removed, a schedule for vegetation removal and replanting, and the method of vegetation removal. Located on page(s) Page 5 (9) Recommendations for the preparation of a detailed temporary erosion control plan w ich identifies the specific mitigating measures to be implemented during construction to p otect the slope from erosion, landslides and harmful construction methods. Located on page(s) Page 5 (10) An analysis of both on-site and off-site impacts of the proposed development. Located on page(s) Page 5 (11) Specifications of final development conditions such as, vegetative management, drair age, erosion control, and buffer widths. Located on page(s) Page 5 (12) Recommendations for the preparation of structural mitigation or details of other proposed mitigation. Located on page(s) Page 5 (13) A site map drawn to scale showing the property boundaries, scale, north arrow, and the location and nature of existing and proposed development on the site. Located on Ma s Plan Sheets 1 & 2 I, Alan A.Tahia,P.E. hereby certify under penalty of perjury that I am a civil engineer licensed in the State of Washington with specialized knowledge of geotechnical/geological engineering or a geologist or engineering geologist licensed in the State of Washington with special knowledge of the local conditions. I also certify that the Geotechnica Reports, dated 5/10/2013 , and entitled Mark Fenton Geotechgical Report meets all the r quirements of the Mason County Resource Ordinance, Landslide Hazard Section, are complete and true, that the reports demonstrates conclusively that the risks posed by the landslide hazard can be mitigated through the included geotechnical design recommendations, and that all hazards are mitigated in such a manner as to prevent harm to property and public health and safety. (Signature and Stamp) A. T 0 WAS i .' EGIs]ERA ' �SSY0 L Page 2 of 2 Form Effective June 2008 Disclaimer: Mason County does not certify the quality of the work done in this Geotechnical Report. TAHJA ENGINEERING, Inc. PO Box 235, Hoodsport, WA 98548 (360) 877-9512 Mason County DCD PO Box 279 Shelton, WA 98584 Mark Fenton 301 E Wallace-Kneeland Blvd ST224-233 Shelton, WA 98584 (360) 401-9229 RE: Residential Geotechnical Report(s) W Dayton Trails Drive Shelton, WA 98584 Mason Co. Prcl No. 42008-14-9 042 & 42008-14- 043 Mason Co. Case No.s WEL2013 00011 SWG2!013-00072 SWG2013 00071 INTRODUCTION I was contacted in April of 2013 by Mr. Mark Fenton who requested my investigation aid documentation of slope stability and landslide hazard issues relating to improvements panned on his residential properties identified above. The Fenton properties are located in an area appi oximately six miles west and north of Shelton, Mason County Washington. I've visited the property in April and May of this year to collect topographic informatio and verify measurements and feature locations. Measurements were made using a Sokkia model No. 8047-55 inclinometer, 100 foot and 300 foot long fiberglass surveyor's tapes and other field equ pment common to surveying. Software employed in creating a site plain and writing this report included AutoCAD 2006, a Terrain 3-d contour modeling program, GALENA Slope Stability A alysis software, and Microsoft Office Word 2003. The slopes located on the Fenton properties range from level on the north end of the two parcels to slopes ranging between 35 and 38% on the southerly portion of the easterly parcel (Tract 42). Neither of the two Fenton properties contains slopes greater than 40%, but both parcels are within 300 feet of slopes on an adjacent property that were measured at 60% over an elevation difference of approximately 40 feet. A gravel borrow pit has been developed)on the property immediately west of the southerly half of parcel 42008-14-90042 and immediately south of parcel 42008-14 90043. The pit slopes were measured at 60%towards the north and east. The gravel pit and slopes are identified on the attached site plans as a HAZARD AREA because the pit slopes are greater than 0% with more than 10-feet of vertical relief. The upslope geomorphology of the Fenton property may be described as flat. Because of the steep slopes (>40% under Mason County terminology) on or within 300 feet of the owner's properties, Mason County requires a geotechnical report be prepared to addres potential stability issues relating to the properties' development. File: C:I Projects Tenton l Geo-Rpt I of 6 5110/ 013 K 1 TAHJA ENGINEERING, Inc. PO Box 235, Hoodsport, WA 98548 (360) 877-9512 The following thirteen elements are required by Mason Count o be addressed in geot hnical reports prepared to comply with Mason County's Critical Resoirce Ordinance Sections 17.01.100 through 17.01.104. 1. SURFACE AND GEOLOGIC C NDITIONS: The property is located in the rolling foothills south of the Ol pic Mountain range.NC arly all of the Fenton site has been logged at some distant past time and now is typically covered with a fairly even age stand of second growth timber, comprised mainly of Douglas fir, hemlock, cedar, and Jack Pine trees. An Onsite Septic System(OSS) is planned for each of the two arcels under Mason Coimty Onsite Septic System Permits SWG2013-00071 & 00072. Greg Waldi' k designed the septic systems. Discussing soil conditions and depths with Greg, Greg reported that he had designed several septic systems in the W Dayton Trails community, and that the gravel pparent at the ground urface extended to a great depth throughout the area. The properties p' se no problems for sitting septic system components. A water well has been drilled on tract 3 in the location indicated or.the attached site plans. Inspection of the portion of Department of Natural Resources) 3eologic map of the Shelton area on the following page finds the Fenton property located in an area oughly 2 miles east anc north of Dayton and roughly 6 miles west and north of Shelton. Them and onsite investigatio of the site's soils reveals the areas surrounding the Fenton property are mai y Continental Glacial Deposits (Qgo) described as follows; Continental Glacial Deposit : Fraser Glaciation,Vashon Stade Proglacial and recessional outw°ash,late WisciiIi iinan(Pleisto- cene)—Typically poorly to moderately sorted,rounded gravel and sand with localized coarser-and finer-grained co tituerrts;lithologi- cally varied mixture of mostly northern-provenan clasts,especially containing granitic and metamorphic rocks that i ntify the unit as ,being deposited by the Puget lobe of the Cordillejan glacier;also con- tains varying amounts of locally derived Crescent omration basalt, sand in the Max Chehalis Creek valley,central Cascade Range— derived andesitic clasts;typically shades of gray ere fresh or brown where stained especially in proglacial and porainal areas; buff staining near the ground surface;fine sand,silt a clay constitute local overbank sediments having relatively poor rmeability or del- taic toreset bedding along north sides of valleys Ny th higher permea- bility;porous and permeable enough to yield sm•+ to moderate quan- tities of groundwater;very poorly consolidated to oose;moderately to well-rounded clasts;mostly unweathered with tare weathered reworked clasts;thickness varies and is not well own;most com- monly occupies outwash channels scoured into or,through till. r DNR OFR2003-15 Geologic Map of Shelton 1:100,000 Quadrangle,Washington File:C:IProjectsTentonlGeo�iRpt 2 of 6 5/10/ 013 TAHJA ENGINEERING, Ioc. PO Box 235, Hoodsport, WA 198548 (360) 877-9512 V Mc In jt k' ~~` C ` Tties , i Oa 6 � F n 4 - r m � _ w Inspection of Washington State Ecology's Landslide Hazard Maps reveals that the Fenton properties and surrounding area are classified as STABLE. Further inspection and soil analysis finds the soil to be classified under the Unified Soil Classification System (USCS) as a GW (well graded gravel & sandy gravels) soil division. Probing various areas of the Fenton property found fairly consistent soil characteristics over both parcels with roughly 3 feet of moderately compacted gravel over more consolidated gravel below a depth of roughly 3 feet. No upland water bodies or wetlands were found anywhere near or on the Fenton properties. 2. SITE PLAN WITH IMPORTANT DEVELOPMENJ AND GEOLOGIC FEATURES: A site plan showing the general topography of the area surrounding the Fenton properties is attached in this report's appendix. Plan sheet two of the plan set shows the locations of existing I eologic features. 3. LOCATIONS OF LOGS OF EXPLORATORY JIOLES OR PROBES: The attached site plan shows the locations of soil probing on the Fenton property along ith measured depths to the underlying more compact gravel layer. The undisturbed areas o the Fenton property revealed a fairly typical weathered gravel layer 3-feet(thick resting on top of a more densely compacted gravel soil. 4. AREA OF PROPOSED DEVELOPMENT & BOJINDARIES OF HAZARDS BUFFERS,AND SETBACKS: The attached site plan shows the locations of the existing and proposed Fenton property improvements, the locations of the hazard areas (slopes> 40%), and the boundary of a 0' buffer line out from the crest and toe of the steep slopes located near the Fenton property. File:C:TrojectsTentonlGeo-Rpt 3 of 6 5/10/ 013 4 1 1 TAHJA ENGINEERING, Inc. PO Box 235, Hoodsport, WA 98548 (360) 877-9512 The Fenton properties themselves contain no slopes steep enough to trigger the requirements for a geotechnical report level report. The gravel pit excavation on the adjacent property triggered a geotechnical report level investigation and report, but any deve opment planned for the Fenton properties will be more than 50-feet away from any hazard area: itself, and no greater separation is needed to protect Fenton property improvements. 5. CROSS SECTION WITH PROPOSED GRADE CHANGES: A cross section view of each of the Fenton property parcels is provided in the attached Ian sheets as well as part of the GALENA Stability Analysis Print-Out. The currently anticipated property improvements will not require the construction of any structural fill sections or changes to the existing slopes or grades. 6. SLOPE STABILITY ANALY IS: The property itself does not display any instability indicators. For stability analysis,the illside soils were investigated and have been characterized as moderately compacted gravelly sand to a depth of roughly 3-feet where the gravel becomes more compact to an infinite depth. Unified Soil Classification System (USCS)typing places the soils in a GW symbol category (sandy ravel). The soils are modeled as a homogenous GW soil characterized with a soil unit weight o 125 lbs/ft3, a phi angle of 38°, and a cohesion character of 501bs/ft2. The Boor of the gravel pit was found to have standing water, so the gravel pit floor (el. 300) is assumed,to represent the phreatic water elevation in the project area. The slope geometry and soil characteristics provide factors of safety for both Fenton p cels in a static and a dynamic analysis that exceeds the County's minimum safety requirements. The gravel pit slopes were measured at 60% or less. Two slopes which could potentially impact one or both of the Fenton parcels were analyzed with the following Factors of Safety (FoS); Parcel 42008-14-90042 Tract"2" Cross Section"B" Static FoS: 1.91 Dynamic FoS: 1.44 Parcel 42008-14-90043 Tract"3" Cross Section"A" Static FoS: 2.37 Dynamic FoS: 1.72 7. RECOMMENDED SETBACKS & DRAINAGE: Slope stability analysis indicates that the southerly & westerly descending slopes locate I west and south of the Fenton properties are stable in their present geome and condition and do not represent a landslide or geological hazard to the anticipated development f the properties. Conformance to building department building setbacks (20' sideyard) will provi.de adequate separation between the hazard slopes, hazard area buffers and any property improvem ts. File: C:IProjectsTentonlGeo-Rpt 4 of 6 5/10/ 013 TAHJA ENGINEERING, Ioc. PO Box 235, Hoodsport, WA 198548 (360) 877-9512 The gravelly soils on the Fenton properties infiltrate all precipitation delivered to the gr und's surface. Drainage from the developed areas of the Fenton properties should be dispersec.into vegetated areas of the property and allowed to disperse. The separation between the anticipated Fenton property improvements and the hazard area slopes is great enough that stormwater from the Fenton properties will have no impact on the neighboring properties' slopes or the mod rate slopes (<40%) on the Fenton parcels. 8. CLEARING, GRADING,AND VEGETATION MANAGEMENT: The proposed Fenton property improvements will generally occur in the already cleared and leveled areas of the property in the northerly half of each tract. No grading or disturbance of the steep sloping areas on the property are being proposed, so no mitigation or changes to the moderately sloping areas of the property appears needed other than the drainage recommendations lready made in this report. Natural vegetation should be promoted on the sloping areas south of the properties. A formal clearing, grading & vegetation plan does not appear warranted for the Fenton properties. 9. EROSION AND SEDIMENT ONTROL: Inspection of the Soil Survey of Mason County found Shelton ravelly sandy loam and rove gravelly sandy loams neither of which are identified in the Comity's Critical Resource rdinance as susceptible to severe erosion when disturbed, and do not require the development of a s to specific erosion and sediment control plan. Each of the two Fenton sites has already had an access developed from W Dayton Trail Drive which are stable in their present conditions. The planned property improvements are generally located well inside the Fenton property boundaries. The Fenton properties themselves provide adequate filtration length through natural vegetation to provide for water quality treatment before any stormwater runoff is able to escape the property. 10. ON-SITE AND OFF-SITE IM ACTS: Construction and completion of the conjectural property impro ements on the Fenton pi operties are not expected to result in any adverse on-site or off-site impacts, 11. SPECIFICATIONS OF FINAL DEVELOPMENT: Completion of the Fenton property improvements does not require any special specific ions for project completion other than already made earlier in this report and as identified on the attached site plans. Building elements are expected to comply with Mason County's current International Building Code or International Residential Code requirements. 12. RECOMMENDATIONS FOR THE PREPARATION'OF STRUCTURAL MITIGATION OR DETAILS OF OTHER PROPQSED MITIGATION: Modeling of the slopes in the proximities of the conjectural property development(s) indicates that the proposed Fenton property development will be safe. No structural measures appear necessary other than ensuring that foundation footings bear on the moderately compact native soil underlying the Fenton property, and that stormwater runoff is properly managed/dispersed to minimize concentrated flows of stormwater runoff off the Fenton property. File: C:TrojectsTentonlGeo-Rpt 5 of 6 5110/ 013 TAHJA ENGINEERING, Inc. PO Box 235, Hoodsport, WA :98548 (360) 877-9512 13. SITE PLAN WITH THE LOCATION OF EXI TING AND PROPOSED DEVELOPMENT ON THE SITE: A site plan is attached as an appendix to this report and is hereby made a part of this report along with the cross section views of the property and the stability analysis printouts. Summary & Conclusions: The proposed Fenton property development can be accomplished according to the owner's plans provided recommendations made in this report are implemented and incorporated into the site's development plans. Please feel free to contact me if there are any questions or concerns regarding this report or my findings. Sincerely, T WA i �p 307a� Cyr S1 ERA ' �SStONAL�1yGti Alan A. Tahja, P.E. Attached: Plan Views & Cross Section Sheets GALENATM Stability Analysis Printouts (2) File:C:TrojectsTentonlGeo-Rpt 6 of 6 51101 013 Rev# Description Date TAHJA ENGINEERING,INC. SXTE PLAN . Alan Tahja,P.E. Mark Fenton Fenton PO Box 235 .301 E Wall-Knee Blvd ST224 233 Mkmt Hoodspork WA 98548 Shelton, WA 98584 1 of4 Mason Co.Prcl No.:42008-14-90042&43 (360)877-9512 360) 401-9229 I z � I � w 03 I 0VO �, = s VO \ " II a I I N rq ri l 06 I w 0 0 '00£ d) u►'I,Cuado d or a! Q d A N s E 00 cn o \ c o C) v N a / o ct Rev# Description Date TAHJA ENGINEERING,INC. SITE PLAN Alan Tahja,P.E. Mark Fenton Fenton PO Box 235 $01 E Wall-Knee Blvd ST224 233 Hoodspork WA 98548 ,Shelton, WA 98584 2 of Mason Co.Prcl No.:42008-14-90042&43 (360)877-9512 (360) 401-9229 ro 0 � dN• I W O O O O z � G v O z z = I o c N SUr = _ _ r' r 099 Zd - - -� — — — o- - - -- -- — r 0 0 I N O bA O 3 I w kr) cd a o o, o cq: / \ o ,��, r — 3 SOF ?d / a1 a � y� > d '00 (I )oun Xuadoid C7 x I Ncn O in �n W N N 1 } 02� Rev# Description Date TAHJA ENGINEERING,INC. SITE PLAN Alan Tahja,P.E. Mark Fenton Fenton PO Box 235 301 E Wall-Knee Blvd ST224 233 , HoodspoA WA 98548 Shelton, WA 98584 3 of4 Mason Co.Prel No.:42008-14-90042&43 (360)877-9512 (360) 401-9229 � I I� p O R� C) mw v, 05 o -o o N sue. p Z" � 4-4 U U cn cn O U \ M Qco�e� \ N \ I \ 09£ M -- --- - - - --- --- --- --- - \ \ Rev# Description Date TAHTA ENGINEERING,INC. S TE PLAN Alan Tahja,P.E. Mark Fenton Fenton PO Box 235 �01 E Wall-Knee Blvd ST224 233 Hoodsport, WA 98548 helton, WA 98584 4 of Mason Co.hr No.:42008-14-90042&43 (360)877-9512 (360) 401-9229 � o Qb o �6Q u o w a U o \ o \ Q � 7� S \ ado J� \` \ p / ado` / z / a O o U C) 1 N M 4,o i cry �iMLALA � �Ww 93 z 0 / � N a" 2 / C7 TAHJA ENGINEERING, Inc. PO Box 235, Hoodsport, WA 98548 (360) 877-9512 Fenton L)ayton Trails Tract 3 X-Section A-A S �ic Stability Analysis GA LENA V....5.02 450 440 azo A. aoo �r�, 0 WA o 380 360 Development Area y /� �754 Sao ' �asr. 0,' GISTS-a 6os Sia �S 10NAL e Homogenous sandy(rave. ,cp, 320 Gravel Pit Phr oatic Surface \ 300 ._.._.. .I ------- .._---._...___-._---- -----. ..,...,,_,.__.._.... .. -"' Anal sis 1 Multiple Stability Analysis 280 Method: 3ishop Simplified Surface: ircular 260 Results critical(m imum) Fao for of Safety: 2.37 240 0 50 100 150 200 250 31 EWted:10 h ay 2013 Processed:10 May 2013 Proiect: Fenton TR3 Static File: CADocumerds and Settings\Owner\MyIDocuments\Galena Files\Models\Fenton TR3.gmf Tahja E gineellingr Inc. Galena 5.02 Analysis results Lice ee: Tahja Engineering, Inc. DATA: Analysis 1 - Static Material Properties (1 material) ------------------- Material: 1 (Mohr-Coulomb Cu increases with depth) - Cohesion Phi PI UnitWeight Ru 50.00 38.0 0 125.00 1.10 Water Properties ---------------- Unit weight of water: 62.40 Unit weight of water/m iium above ground: 62.40 Material Profiles (1 profile) ----------------- Profile: 1 (2 pointsp Material beneath: 1 - 0.00 400.00 300.00 400.00 Slope Surface (4 points) ------------- 0.00 350.00 120.00 340.00 183.00 10.00 290.00 300.00 Phreatic Surface (2 points) --- 0.00 300.00 300.00 300 00 Failure Surface --------------- i Initial circular surface for critical search defined XL,XR,R Intersects: XL: 120.00 YL: 340.00 XR: 183.00 YR: 10.00 Centre: XC: l59. 91 YC: 342.66 Radius: R: 40.00 Variable Restraints ------------------- Parameter descriptor: XL XR R Range of variation: 60.00 60.00 40.00 Trial positions within range: 12 12 12 RESULTS: Analysis 1 - Static Bishop Simplified Method of Analysis - Circular Failur Surface i File:C.IProjectslFenton TR3 X-Soc A-A Analysis Printout 1 of 4 5/10/2013 TAHJA ENGINEERING, Ind. PO Box 235, Hoodsport, WA 548 (360) 877-9512 Critical Failure Circle Search using Multiple Circle generation Technique Factor of Safety for initial failure circle approximation: 3.34 There were: 1083 successful analyses from a total of 1729 trial circles 646 analyses terminated due to unacceptable geometry Critical (minimum) Factor of Safety: 2.37 Circle and Results Summary (Lowest 23 Factor of Safet) circles) --------- ------- Circle X-Centre Y-Centre X-Left Y-Left X-Right Y-Right Radius FoS 1 169.33 376.49 122.73 338.701 169.36 315.49 60.00 2.370 2 180.24 371.30 133.64 333.51 180.27 31 .30 60.00 2.370 3 174.78 373. 90 128.18 336.10 174.82 313. 90 60.00 2.370 4 176.85 371.20 128.18 336.101 180.27 31 .30 60.00 2.374 1 5 171.39 373.80 122.73 338.701 174.82 313. 90 60.00 2.374 6 181.57 369. 60 133.64 333.511 185.73 30 .75 60.00 2.383 7 162. 99 379.08 117.27 340.23i 163. 91 31 ).09 60.00 2.383 8 167.58 372.83 122.73 338.70 169.36 315.49 56.36 2.384 9 178.49 367. 63 133.64 333.51 , 180.27 31 .30 56.36 2.384 10 173.04 370.23 128.18 336.10 174.82 313. 90 56.36 2.384 11 165.18 376.35 117.27 340.23 169.36 315.49 60.00 2.389 12 184.83 369.74 139.09 330.91 185.73 30 ).75 60.00 2.395 13 167.18 379.00 122.73 338.70 : 163. 91 31 ).09 60.00 2.396 14 178.09 373.81 133. 64 333.51 174.82 313. 90 60.00 2.396 15 183.54 371.21 139.09 330. 91 180.27 31 .30 60.00 2.396 16 172. 63 376.40 128.18 336.10 169.36 315.49 60.00 2.396 17 181.84 367.64 139.09 330.91 180.27 31 .30 56.36 2.398 18 170.93 372.84 128.18 336.10 169.36 315.49 56.36 2.398 19 176.39 370.24 133.64 333.51 174 .82 313.90 56.36 2.398 20 165.48 375.43 122.73 338.70 163.91 319.09 56.36 2.398 21 161.32 375.40 117.27 340.23 163.91 31).09 56.36 2.400 22 169.59 370.02 122.73 338.70 174.82 313.90 56.36 2.400 23 175.05 367.42 128.18 336.104 180.27 31 .30 56.36 2.400 I i File:C.•IProjectslFenton TR3 X--Slc A-A Analysis Printout 2 of 4 5/10/2013 TAHJA ENGINEERING, Ine. PO Box 235, Hoodsport, WA 548 (360) 877-9512 Fenton Dayton Trails Tract 3 X-Section A-A Dyn Oic Stability Analysis GA ENA ve a oo s.o2 aso i 440 o�so� 420 400 I 380 360 Geve:opment Area 340 ��� bee94r "°6 No geto,la Sandy gravel �g SI°oe 320 Gravel Pit uric Surface 300 ---------- Pr---------- _.,__________. _-._._ __._.. - A�� ___- Anal si 1 Multiple Stability Analysis 280 Method: 3ishop Simplified Surface: ircular 260 Results Critical(m imum) Fa tor of Safety: 1.72 240 0 50 100 150 200 250 300 Etlired:10 y 2013 Processed'10 May 2713 Proiect Fenton TR3 Dynamic File: C:\Documents and Settings\Owner\fvly,Documents\Galena FilesXModels\Fenton TR3.gmf Tahja Engineering,Inc. Galena 5.02 Analysis Results Lice; ee: Tahja Engineer'ng, Inc. DATA: Analysis 1 - Dynamic Material Properties (I material) ------------------- Material: 1 (Mohr-Coulomb Cu increases with depth) - Cohesion Phi PI UnitWeight Ru 50.00 38.0 0 125.00 1.10 Water Properties ---------------- Unit weight of water: ', 62.40 Unit weight of water/me ium above ground: 62.40 Material Profiles (1 profile) ----------------- Profile: 1 (2 points) Material beneath: 1 - 0.00 400.00 300.0 400.00 Slope Surface (4 points) ------------- 0.00 350.00 Q20.00 340.00 183.00 310.00 290.00 300.00 Phreatic Surface (2 points) --- 0.00 300.00 300.00 300. 0 Failure Surface ----- ---------- Initial circular surface for critical search defined : XL,XR,R Intersects: XL: 120.00 YL: 340.00 XR: 183.00 YR: 310.00 Centre: XC: 159. 91 YC: 342.66 Radius: R: 40.00 Earthquake Force ---------------- Pseudo-static earthquake (seismic) coefficient: 0.15 Variable Restraints ------------------- Parameter descriptor: XL XR R Range of variation: 60.00 60.00 40.00 Trial positions within range: 12 12 12 RESULTS: Analysis 1 Dynamic File:C:IProjectslFenton TR3 X-S4c A-A Analysis Printout 3 of 4 5/10/2013 i i I 1 TAHJA ENGINEERING, IIJU. PO Box 235, Hoodsport, WA 548 (360) 877-9512 Bishop Simplified Method of Analysis - Circular Failu' Surface --------- Critical Failure Circle Search using Multiple Circle Uneration Technique Factor of Safety for initial failure circle approxima' 'on: 2.46 There were: 1083 successful analyses from a total of 1.729 trial circles 646 analyses terminated due to unacceptabla geometry Critical (minimum) Factor of Safety: 1.72 Circle and Results Summary (Lowest 99 Factor of Safetj, circles) --------- ----- Circle X-Centre 'Z-Centre X-Left Y-Left X-Right Y-Right Radius FoS 1 169.33 376.49 122.73 338.70 169.36 315.49 60.00 1.717 2 180.24 371.30 133. 64 333.51 180.27 31 .30 60.00 1.717 3 174.78 373. 90 128.18 336.10 174.82 313. 90 60.00 1.717 4 176.85 371.20 128.18 336.10 180.27 31 .30 60.00 1.720 5 171.39 373.80 122.73 338.70 174.82 313. 90 60.00 1.720 6 162.99 379.08 117.27 340.23 163.91 31 ).09 60.00 1.723 7 181.57 369.60 133. 64 333.51 185.73 30 ).75 60.00 1.726 8 167.58 372.83 122.73 338.70 169.36 315.49 56.36 1.727 9 178.49 367.63 133. 64 333.51 180.27 31 .30 56.36 1.727 10 173.04 370.23 128.18 336.101 174.82 313. 90 56.36 1.727 i 11 165.18 376.35 117.27 340.23 ' 169.36 315.49 60.00 1.729 12 184.83 369.74 139.09 330. 91 185.73 30 ).75 60.00 1.735 13 160.68 381.65 117.27 340.23 158.45 32 . 69 60.00 1.735 14 167.18 379.00 122.73 338.70 163. 91 31).09 60.00 1.735 15 178.09 373.81 133.64 333.51 . 174.82 313.90 60.00 1.735 16 183.54 371.21 139.09 330. 91 180.27 31 .30 60.00 1.735 17 172.63 376.40 128.18 336.10 ' 169.36 315.49 60.00 1.735 18 161.32 375.40 117.27 340.23 163. 91 31 ).09 56.36 1.736 19 181.84 367. 64 139.09 330.91 180.27 31 .30 56.36 1.737 20 170. 93 372.84 128.18 336.10 169.36 315.49 56.36 1.737 21 165.48 375.43 122.73 338.70' 163.91 31).09 56.36 1.737 22 176.39 370.24 133.64 333.51 174.82 313.90 56.36 1.737 23 178.18 369.27 128.18 336.10 185.73 30).75 60.00 1.741 File:C:IProjectslFenton TRi X-SeIc A-A Analysis Printout 4 of 4 5/10/2013 r r r TAHJA ENGINEERING, Inc. PO Box 235, Hoodsport, WA 8548 (360) 877-9512 Fenton Dayton Trails Tract 2 X-Section B-B Sto is Stability Analysis GAILENA Vemtlum 5.02 460 440 ago 400 380 360 Development Area 31)78� 340 5,� � Cl 7 8 4 0NAL 320 Gravel Pic @aa J mogenous Sandy Gravel ea ci¢Surface Anal sis 1 280 Multiple Stability Analysis Method: 3ishop Simplified 260 Surface: ircular I Results 240 critical(m imum) Fa or of Safety: 1.91 0 50 100 150 200 250 300 350 Etlifetl:10 y 2013 Proce d.10 May 2013 Proiect Fenton TR2 Static Eft, C:\Documents and Settings\Owner\My..Documents\Galena Files\Models\Fenton TR2 S.gmf Tahja Engineering,Inc. Galena 5.02 Analysis Results Licensee: Tahja Engineering, Inc. DATA: Analysis 1 - Static Material Properties (I material) ------------------- Material: 1 (Mohr-Coulomb Cu increases with depth) - Cohesion Phi PI UnitWeight Ru 50.00 38.0 0 125.00 1.10 Water Properties ---------------- Unit weight of water: 62.40 Unit weight of water/medium above ground: 52.40 Material Profiles (1 profile) ----------------- Profile: 1 (2 points) Material beneath: 1 - 0.00 400.00 350. )0 400.00 Slope Surface (4 points) ------------- 0.00 300.00 175.00 302.00 238.00 3 D.00 347.00 350.00 Phreatic Surface (2 points) --- 0.00 300.00 350.00 300 00 Failure Surface ----- --------- Initial circular surface for critical search defined XL,XR,R Intersects: XL: ,J73.00 YL: 301.98 XR: 240.00 YR: 340.18 Centre: XC: 198.26 YC: 335.53 Radius: R: 42.00 Variable Restraints -'------------------ Parameter descriptor:' XL XR R Range of variation: 60.00 60.00 45.00 Trial positions within range: 12 12 12 ----------------------------------------------------- ------------------ ------- RESULTS: Analysis 1 Static Bishop Simplified Method of Analysis - Circular Failur Surface i File:C.IProjectslFenton TR2 X-SPc B-B Analysis Printout 1 of 4 5/10/2013 TAHJA ENGINEERING, Inc. PO Box 235, Hoodsport, WA 548 (360) 877-9512 Critical Failure Circle Search using Multiple Circle Ganeration Technique Factor of Safety for initial failure circle approxima 'on: 2.80 There were: 1000 successful analyses from a total of 29 trial circles 729 analyses terminated due to unacceptab geometry Critical (minimum) Factor of Safety: 1.91 Circle and Results Summary (Lowest 23 Factor of Safet circles) --------- ------- Circle X-Centre �-Centre X-Left Y-Left X-Right Y-Right Radius FoS 1 182.35 373.38 186.64 309.02 237.27 33 ).56 64.50 1. 907 2 176.89 370.09 181.18 305.73 231.82 335.27 64.50 1. 907 3 171.44 366.80 175.73 302.44 ' 226.36 33 . 98 64.50 1. 907 4 184.28 376.33 192.09 312.31 237.27 33 ).56 64 .50 1. 909 5 173.37 369.75 181.18 305.73 226.36 33 . 98 64.50 1.909 6 178.83 373.04 186.64 309.021 231.82 335.27 64.50 1.909 7 167. 92 366.46 175.73 302.44 220. 91 32 ). 69 64.50 1. 909 8 175.70 365.89 181.18 305.73 226.36 33 . 98 60.41 1. 919 9 186. 61 372.47 192.09 312.31 237.27 33 .56 60.41 1. 919 10 181.16 369.18 186.64 309.02 231.82 33 .27 60.41 1.919 11 170.25 362.60 175.73 302.44 220. 91 32 ). 69 60.41 1. 919 12 180.53 370.23 181.18 305.73i 237.27 33 ).56 64.50 1.925 13 175.07 366.94 175.73 302.44 231.82 33 .27 64 .50 1. 925 14 179.29 366.11 181.18 305.73 231.82 33 .27 60.41 1. 927 15 184.75 369.40 186.64 309.02 237.27 33 ).56 60.41 1. 927 16 173.84 362.82 175.73 302.W 226.36 33 .98 60.41 1. 927 17 188. 98 368.54 192.09 312.31 237.27 33 ).56 56.32 1.934 18 178.07 361.96 181.18 305.73 226.36 33 .98 56.32 1.934 19 183.53 365.25 186. 64 309.02 231.82 335.27 56.32 1. 934 20 172.62 358.67 175.73 302.44I 220. 91 32 ). 69 56.32 1. 934 21 166.78 362.18 175.73 302.44 215.45 325.40 60.41 1. 936 22 188.60 375.34 197.55 315. 60 237.27 33 .56 60.41 1. 936 23 183.15 372.05 192.09 312.31 231.82 335.27 60.41 1. 936 File:C.•IProjectslFenton TR2 X-See B-B Analysis Printout 2 of 4 5/10/2013 r • r TAHJA ENGINEERING, Inc. PO Box 235, Hoodsport, WA 93548 (360) 877-9512 Fenton Dayton Trails Tract 2 X-Section B-B Dynamic Stability Analysis GAf,ENA Verelun5.02 450 440 420 400 380 360 Development Area 340 6� 320 a°i¢a mogenous sandy Grave; Grave:Pit rnreatn,5 rSce 300 -------.-----......-- ------_.._ -_........._ Anal sis 1 280 Multi le Stability Analysis Method: 3ishop Simplified 260 Surface: ircular Results 240 Critical(m imum) Fa or of Safety: 1.44 0 50 100 150 200 250 300 350 Edited.10 y 2013 Processed-10 May 2013 Proiect: Fenton TR2 Dynamic File: CADocuments and Settings\Cwner\My Documents\Galena Files\IelodelsTenton TR2 D.gmf Tahja Ei gineering,Inc. Galena 5.02 Analysis Results Lice' ee: Tahja Engineer'ng, Inc. DATA: Analysis 1 - Dynamic Material Properties (1 material) ------------------- Material: 1 (Mohr-Coulomb Cu increases with depth) - Cohesion Phi PI UnitWeight Ru 50.00 38.0 0 125.00 1.10 Water Properties ---------------- Unit weight of water: 62.40 Unit weight of water/med m above ground: 62.40 Material Profiles (1 profile) ----------------- Profile: 1 (2 points) Material beneath: 1 - 0.00 400.00 350.00 400.00 Slope Surface (4 points) ------------- 0.00 300.00 175.00 302.00 238.00 340 0 347.00 35 .00 Phreatic Surface (2 points) --- 0.00 300.00 350.00 300.00 Failure Surface ----- ---------- Initial circular surf ace for critical search defined : XL,XR,R Intersects: XL: 173.00 YL: 301.98 XR: 240.00 YR: 340.18 Centre: XC: 198.26 YC: 335.53 Radius: R: 42.00 Earthquake Force ----'------------ Pseudo-static earthquake (seismic) coefficient: 0.15 Variable Restraints ------------------- Parameter descriptor: XL XR R Range of variation: 60.00 60.00 45.00 Trial positions within range: 12 12 12 File:C.IProjectslFenton TR2 X-S�c B-B Analysis Printout 3 of 4 5/10/2013 TAHJA ENGINEERING, Inc. PO Box 235, Hoodsport, WA 98548 (360) 877-9512 RESULTS: Analysis 1 Dynamic Bishop Simplified Method of Analysis - Circular Failu' Surface --------- -- Critical Failure Circle Search using Multiple Circle neration Technique Factor of Safety for initial failure circle approxima ' on: 2.16 There were: 1000 successful analyses from a total of 1729 trial circles 729 analyses terminated due to unacceptable geometry Critical (minimum) Factor of Safety: 1.44 Circle and Results Summary (Lowest 22 Factor of Safety circles) --------- -------- Circle X-Centre Y-Centre X-Left Y-Left X-Right Y-Ri ht Radius FoS 1 182.35 373.38 186.64 309.02 237.27 33).56 64.50 1.438 2 176.89 370.09 181.18 305.73i 231.82 335.27 64.50 1.438 3 171.44 366.80 175.73 302.44 226.36 332. 98 64.50 1.438 4 184.28 376.33 192.09 312.31 237.27 33).56 64 .50 1.438 5 173.37 369.75 181.18 305.73 226.36 33 . 98 64.50 1.438 6 178.83 373.04 186. 64 309.02 231.82 335.27 64 .50 1.438 7 167.92 366.46 175.73 302.44 220.91 32 ).69 64 .50 1.438 8 175.70 365.89 181.18 305.73 226.36 33 .98 60.41 1.446 9 186.61 372.47 192.09 312.31 237.27 33).56 60.41 1.446 10 181.16 369.18 186. 64 309.02 231.82 335.27 60.41 1.446 11 170.25 362.60 175.73 302.44 220. 91 32 ). 69 60.41 1.446 12 180.53 370.23 181.18 305.731 237.27 33).56 64.50 1.453 13 175.07 366. 94 175.73 302.44 231.82 335.27 64.50 1.453 14 179.29 366.11 181.18 305.73 231.82 335.27 60.41 1.454 15 184 .75 369.40 186. 64 309.02 237.27 33).56 60.41 1.454 16 173.84 1 362.82 175.73 302.44 226.36 332. 98 60.41 1.454 17 188. 98 368.54 192.09 312.31 237.27 33).56 56.32 1.459 18 178.07 361.96 181.18 305.73, 226.36 332. 98 56.32 1.459 19 183.53 365.25 186. 64 309.02. 231.82 336.27 56.32 1.459 20 172.62 358.67 175.73 302.44 220. 91 329. 69 56.32 1.459 21 166.78 362.18 175.73 302.44 215.45 326.40 60.41 1.460 22 188. 60 375.34 197.55 315. 60 237.27 339.56 60.41 1.460 File: C:IProjectslFenton TR2 X-S�c B-B Analysis Printout 4 of 4 5/10/2013