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HomeMy WebLinkAboutGEO2012-00032 for BLD2013-00613, 00623 - GEO Geological Review - 8/23/2013 MASON COUNTY DEPARTMENT OF COMMUNITY DEVELOPMENT Planning Division P O Box 279, Shelton, WA 98584 (360)427-9670 Geotechnical Assessment Review Acceptance Letter August 23, 2013 DON LINCOLN PO BOX 788 BLACK DIAMOND WA 98010 Case No.: GE02013-00032 Parcel No.: 322325080029 Proiect Description: GEO ASSESSMENT SUBMITTED FOR BLD2013-00613 & BLD2013-00623 The Geotechnical Assessment for DON LINCOLN has been received and reviewed by the Planning Department. The assessment was prepared by Michael Staten dated 4/1812012. Based on the certification provided by the licensed engineer/geologist, the referenced Geological Assessment was prepared in general accordance with the requirements in the Mason County Resource Ordinance, Landslide Hazard Areas 17.01.100.E.4. Mason County considers the review valid until such time as scope of project, site conditions, and/or regulations change. Should the scope of work, site conditions, and/or regulations change after the original review, then an addendum from the original author of the assessment may be required to address these changes. The assessment would only be re-reviewed if a permit for development were submitted after these changes occur. Mason County does not certify the quality of the work done in this Geological Assessment. Please contact me at (360) 427-9670, ext. 365 if you have questions. Sincerely, r� Allan Borden Land Use Planner Mason County Planning Department Comments: 8/23/2013 Page 1 of 1 GE02013-00032 *D 2C) ► - opo� RECEIVED ZO i3 - oOC9 �3 JUL 2 5 2013 42b W, CEWST LA B N NG,,, Geological Assessment for Lincoln Single Family Residential Property 81 E Haller Ave Parcel No. 32232 50 80029 & 32232 50 80001 Mason County, Washington April 18, 2012 Project#1243 Prepared For: Don Lincoln PO Box 788 Pti� CLYDE sT Black Diamond, Washington 98010 wA�f ���2 Prepared By: Envirotech Engineering 43045 PO Box 984 ��� GIST6R�° 1�,w Belfair, Washington 98528 SS�DNALI- Phone: 360-275-9374 Fax: 360-275-4789 TABLE OF CONTENTS 1.0 INTRODUCTION...........................................................................................................................1 1.1 PROJECT INFORMATION............................................................................................................... 1 1.2 PURPOSE OF INVESTIGATION AND SCOPE OF WORK..................................................................... 1 2.0 SURFACE CONDITIONS..............................................»..............................................................3 2.1 GENERAL OBSERVATIONS............................................................................................................3 2.2 TOPOGRAPHY...............................................................................................................................3 ZZ1 Upslope Geomorphology and Upland Water Bodies..............................................................3 2.3 SURFACE DRAINAGE.....................................................................................................................3 2.4 SLOPE AND EROSION OBSERVATIONS...........................................................................................3 3.0 SUBSURFACE INVESTIGATION.................................................................................................5 3.1 FIELD METHODS,SAMPLING AND FIELD TESTING........................................................................5 3.2 GEOLOGIC CONDITIONS...............................................................................................................5 3.3 SPECIFIC SUBSURFACE CONDITIONS.............................................................................................5 3.3.1 Groundwater......................................................................................................................... 6 4.0 ENGINEERING CONCLUSIONS...............................................................................................».7 4.1 LANDSLIDE HAZARDS...................................................................................................................7 4.1.1 Landslides and Slope Stability Analysis................................................................................ 9 4.L 2 Surface and Subsurface Drainage........................................................................................ 9 4.2 EROSION HAZARDS.......................................................................................................................9 4.3 SEIsMICHAzARDs........................................................................................................................9 4.4 OTHER CONSIDERATIONS........................................................................................................... 10 5.0 CLOSURE..................................................................................................................................... 11 Appendix A-Site Plan Appendix B -Soil Information 1.0 INTRODUCTION Envirotech Engineering (Envirotech) has completed this geological assessment for a residential property located along E Haller Ave., identified as parcel number 32232 50 80029 in Mason County, Washington (Project). As presented herein, this assessment includes information pertaining to the Project in this Introduction Section; observations of the property and surrounding terrain in the Surface Conditions Section; field methods and soils descriptions in the Subsurface Investigation Section; and, assessments for landslides, erosion, seismic hazards, and other considerations in the Conclusions Section. An initial geological/ geotechnical evaluation of the Project was conducted by Envirotech with the property owner on April 10, 2012. It was determined that natural slopes between 15% and 40% were present within 300 feet of the Project. Due to these slope grades, a geological assessment is required pursuant to landslide hazard areas of the Mason County Resource Ordinance(MCRO). During the evaluation and site visit by Envirotech, surface and subsurface conditions were assessed in order to determine if further geotechnical studies are required. After completion of the field work and applicable Project research, Envirotech prepared this geological assessment. 1.1 Project Information Information pertaining to the Project was provided by the property owner, and observations from a field visit by Envirotech. The property is accessed from E Haller Ave., a paved roadway in Union,Washington. The property consists of an existing driveway, with a single family dwelling and on-site septic features on the neighboring parcel (32232-50-80001). The proposed development is expected to consist of a new garage. Approximate site development with relation to existing site features are illustrated in the Site Map in Appendix A. 1.2 Purpose of Investigation and Scope of Work The purpose of this geological assessment was to evaluate the Project in order to confirm that the proposed development is outside of any landslide hazard area and its associated buffers and setbacks as determined in the MCRO. The investigation included characterizing the general Project surface and subsurface conditions,and evaluating the suitability of the soils to support the planned site development. In order to fulfill the purpose of investigation, the geological/ geotechnical program completed for the proposed improvements of the Project include: • Review project information provided by the Project owner's representative; • Conduct a site visit to document the site conditions that may influence the construction and performance of the proposed improvements; • Define general subsurface conditions of the site by observing soils within test pit excavations, review well logs from existing wells near the Project, and evaluate geological maps depicting the site geology for the vicinity of the Project; • Perform soils testing, such as visual classifications,to determine selected index properties of the soils; • Complete an engineering assessment supported by planned site alterations and the surface and subsurface conditions that were identified by the field investigation, soil testing, and applicable Project research; and, Envirotech Engineering Lincoln Geological Assessment Ph. 360-275-9374 page I Parcel 232232 50 80029 Fax: 360-2754789 Mason County,Washington April 18, 2012 • Establish engineering conclusions based on findings and anticipated Project. o a 's rzzrmaw Q0 y2ORO r22NRNf 11V 4,Y T!���� N STEPNlNS Im ,� T7INR7W SSSO aF0 )- lD1LLDY Rp 1'� C S D *+ CP < i EWIW�AOR � 9 .` � I.. � OO zaS T21NR{vV GO}N 0.O G P11NR9W �.P 0 127NR2W CP Sad �T qP mj; O � •`�' �e OD"I-RI 00 0 '3680f: Vicinity Map from Mason County Website Einzrotech Engineering Lincoln Geological Assessment Ph. 360-275-9374 page 2 Parcel 232232 50 80029 Fax:360-275-4789 Mason County, Washington April 18,2012 2.0 SURFACE CONDITIONS Information pertaining to the existing surface conditions for the Project was gathered on April 10, 2012 by Michael Staten,geotechnical engineer with Envirotech. During the site visit, site features were documented that may influence construction or reveal potential geological hazards. This Surface Conditions Section provides information on general observations, vegetation, topography,drainage and slope/erosion conditions for the Project and surrounding areas. 2.1 General Observations The Project is currently developed land as previously mentioned, and surrounded by semi-rural residential development. Vegetation on and near the property consists primarily of 2nd growth firs, cedars, pines, and other trees and shrubbery common to this area of the Pacific Northwest. An aerial photo of the Project and immediate vicinity is provided on the following page. 2.2 Topography The Project is situated within and near moderate terrain. The topographic information provided in this section was extrapolated from a public lidar source, and incorporated observations and field measurements. Where necessary, slope verification included measuring slope lengths and inclinations with a cloth tape and inclinometer. See the Site Map in Appendix A for an illustration of the general slope indicators with respect to the planned development. Descending slopes exceeding 15%are located to the northeast of the development. This slope is approximately 24%with a vertical relief of approximately 50 feet. 2.2.1 Upslope Geomorphology and Upland Water Bodies Ascending slopes exceeding 15%are located near the planned development. This slope is approximately 19%to 24%with a vertical relief of approximately 20 feet. The property is on a moderate sloping hillside of glacial origin. Additional geomorphology that is pertinent to both upslope and downslope areas are provided in the Subsurface Investigation Section of this report. There are no apparent water bodies or wetlands located upslope from the planned development that would significantly influence the Project. 2.3 Surface Drainage The majority of the stormwater runoff originating upslope from the anticipated development is expected to be minimal to moderate. Significant scour, erosion and sediment transport was not apparent near the development. There is a seasonal stream convergence to the east of the project that appears to contain surface runoff from affecting the development. 2.4 Slope and Erosion Observations The existing moderate slopes near the Project do not signal a potential landslide or erosion hazard area. Some indicators that may suggest past slope movements include: Envirotech Engineering Lincoln Geological Assessment Ph. 360-275-9374 page 3 Parcel 232232 50 80029 Fax: 360-275-4789 Mason County, Washington April 18, 2012 • Outwash of sediments near the bottom of the slope, • Fissures, tension cracks or naturally stepped land masses on the face or top of the slope, and parallel to the slope, • Fine, saturated subsurface soils, • Old landslide debris, • Significant bowing or leaning trees,or, • Slope sloughing or calving. The above mentioned indicators, or other signs of significant mass wasting on the property or within the general vicinity of the Project, were not observed or discovered during research. Indications of past landslides, current unstable slopes, deep-seated slope problems, or surficial slope failures were not observed during the site visit. a -�w r, 9)6 M 4 ' f } V� 4 4. 2009 Aerial Photo from Mason County Website Envirotech Engineering Lincoln Geological Assessment Ph. 360-275-9374 page 4 Parcel 232232 50 80029 Fax: 360-275-4789 Mason County, Washington April 18,2012 3.0 SUBSURFACE INVESTIGATION Information on subsurface conditions pertaining to the Project was gathered during research and a site reconnaissance. The site visit was accomplished on April 10, 2012 by Michael Staten, geotechnical engineer with Envirotech. Specific information on field methods, sampling, field testing, subsurface conditions, and results from soil testing are presented in this section of the report. Appendix B has pertinent information on subsurface conditions for the Project, including test pit log(s) representative of the site soils, and water well report(s)originating from the subject property and/or nearby properties. 3.1 Field Methods,Sampling and Field Testing Information on subsurface conditions for the Project was accomplished by observing soils within test pit excavations of up to approximately 4 feet below the natural ground surface. Information on subsurface conditions also included reviewing geological maps within the Project vicinity, and water well reports originating from nearby properties. No soil samples were collected for this Project. Envirotech measured the relative density of the in-situ soils by gauging the resistance of hand tools. Field testing results generally indicated medium dense soils in the upper 24 inches, and very dense soils from 24 inches below the ground surface to the depth of terminus. 3.2 Geologic Conditions In general, soils at the project are composed of materials from glacial advances. The geologic conditions as presented in the "Geologic Map of Washington," compiled by J. Eric Schuster, 2002 indicates Quaternary sediments, Qg. Quaternary sediments are generally unconsolidated deposits,and dominantly deposited from glacial drift, including alluvium deposits. This project is located within the Puget Lowland. Typically, "lower tertiary sedimentary rocks unconformably overlie the Crescent Formation."as revealed in the Geologic Map. Initial sedimentary rocks were formed from shales, sandstones and coal deposits from rivers. During the Quaternary period, the Puget Lowland was covered by numerous ice sheets,with the most recent being the Fraser glacier with a peak of approximately 14,000 years ago. Upon the glacial retreat, the landscape was formed by glacial erosion glacial drift deposits. The"Geologic Map of the Skokomish Valley and Union 7.5-minute Quadrangles, Mason County, Washington" by Michael Polenz, Jessica L. Czajkowski, Gabriel Legorreta Paulin, Trevor A. Conteras, Brendon A. Miller, Maria E. Martin, Timothy J. Walsh, Robert L. Logan, Robert J. Carson, Chris N. Johnson, Rian H. Skov, Shannon A. Mahan, and Cody R. Cohan, June 2010, provides the following caption(s)for the project area: � Na%hw Ir.•dl-mcnt till—C:r.-art;_. ' i;'�I_]II; _.aa:xt:_�;•3 sYr._, rn¢ttrix: n-:7s1;'y��:': _:,cr:a�a. re•_m,fir:�_ar._r�t�. 3.3 Specific Subsurface Conditions The following subsurface conditions are estimated descriptions of the Project subgrade utilizing information from the depth of penetration at all testing, sampling, observed and investigated locations. Soils for this project were described utilizing the Unified Soil Classification System Envirotech Engineering Lincoln Geological Assessment Ph. 360-275-9374 page 5 .Parcel 232232 50 80029 Fax: 360-275-4789 Mason County. Washington April 18, 2012 (USCS). Using the USCS in conjunction with estimated relative densities and other anticipated engineering properties of the soil, susceptibility for potential landslides, erosion and seismic hazards may be assessed. The Project is composed of native soils beneath an organic/ soil mixture of about 2 to 8 inches. Competent bearing soils were encountered at 12 inches below the ground surface. For engineering purposes,these native soils consist of distinguishable layers,as presented below. Soils within the upper 4 feet of natural ground were observed to be moist,brown silty gravel with sand(GM). Soils below the upper 4 feet layer are believed to be very dense gravelly soils(hardpan)to depths of at least 20 feet. This is based on nearby well reports, site geology, and/ or knowledge of the general area. The relative densities of the soil are provided above in Section 3.1. Expanded and specific subsurface descriptions, other than what is provided in this section, are provided in the soil logs located in Appendix B of this report. According to the "Soil Survey of Mason County," by the United States Department of Agriculture, Soil Conservation Service (SCS), the upland site soils are described as Alderwood gravelly sandy loam (Ad), with 5%- 15%slopes, and Alderwood gravelly sandy loam(Ac)with 15%-30%slopes. See the SCS soil profiles in Appendix B of this report. 3.3.1 Groundwater From the water well report(s)and knowledge of the general area,permanent groundwater is over 100 feet directly below the property at the building pad location. Seepage or perched groundwater at shallow depths was not observed on-site, nor indicated on the well reports. Envirotech Engineering Lincoln Geological Assessment Ph. 360-275-9374 page 6 Parcel 232232 50 80029 Fax: 360-275-4789 Mason County; Washington April 18,2012 4.0 ENGINEERING CONCLUSIONS The following sections present engineering assessments and conclusions concerning the Project. These conclusions have been made available based on the planned construction activities as outlined in the Introduction Section of this report; general observations of drainage and topography as summarized in the Surface Conditions Section; and, soil conditions that were identified by the field investigation and soils testing as outlined in the Subsurface Investigation Section. Conclusions for the Project that is provided herein, includes pertinent information for landslide, erosion and seismic hazards. 4.1 Landslide Hazards For the planned development, as provided in the Introduction Section, surface and subsurface conditions as presented in this report, it is Envirotech's opinion that the proposed development is not subjected to or cause adverse impacts to a landslide hazard area or its associated buffer or setback as defined in the MCRO. Landslides are natural geologic processes, and structures near slopes possess an inherent risk of adverse settlement, sliding or structural damage due to these processes. Geotechnical engineering cannot eliminate these risks for any site with sloping grades because gravity is constantly inducing strain on the sloping soil mass. Excessive wet weather and/ or earthquakes will exacerbate these strains. Geotechnical engineering considers excessive wet weather and `design' earthquakes in order to provide an acceptable factor of safety for developing on or near sloping terrain. These factors of safeties are based on engineering standards such as defining engineering properties of the soil,topography,water conditions, seismic acceleration and surcharges. Surface sloughing or other types of surficial slope movements usually do not affect the deep- seated structural capability of the slope. However, excessive and/or repeated surficial slope movements, if not repaired, may represent a threat to the structural integrity of the slope. Maintenance of the slope should be completed if the situation does arise in order to prevent the possibility of further surficial or deep seated slope movements that may be damaging to life or property. According to the Coastal Zone Atlas of Mason County, Washington, the Project is within and near terrain labeled `Stable' and `Intermediate' regarding potential landslide activity. Stable slopes are generally not prone to landslides due to small grades and accommodating geology. Historically, intermediate terrains have no known landslides. A site specific analyses and conclusions concerning the slopes are presented herein. A Stability Map from the Coastal Zone Atlas for the general area of this Project may be found below. Envirotech Engineering Lincoln Geological Assessment Ph 360-275-9374 pagc 7 Parcel 232232 50 80029 Fax: 360-275-4789 Mason County. Washington April 18, 2012 7 Project Map from Washington State Department of Ecology Website According to the Resource Map from the Washington State Department of Natural Resources (DNR), the Project is not within terrain labeled `highly unstable' or `highly erodible' relating to soils. In addition, DNR did not indicate previous landslide activity near the Project. This delineation is primarily dependent upon slopes and convergence. Secondly, lithology and precipitation are modeled within this delineation. In summary, this designation is based on mapping without field observations or knowledge of the specific site geology or soils. A resource map from DNR is provided below: 79498 04080 I, t 0 F / 94 Project +7040e0 c i Map from Washington State Department of Natural Resources Website Envirotech Engineering Lincoln Geological Assessment Ph. 360-275-9374 page 8 Parcel 232232 50 80029 Fax: 360-275-4789 Mason County,Washington April 18,2012 4.1.1 Landslides and Slope Stability Analysis Past landslide activity near the proposed development was not revealed during the Project research. In addition, detrimental landslide activity or potential high landslide indicators were not observed during the site visit as outlined in the Surface Conditions Section of this report. Therefore, a slope stability analysis was not deemed necessary for this Project. Considering the planned construction as summarized in the Introduction Section of this report; surface and subsurface conditions for the Project; and, the slope stability assessment provided herein, it is our opinion that the proposed site alterations will not encourage a landslide hazard. 4.1.2 Surface and Subsurface Drainage This project does not appear to experience significant subsurface drainage or surface runoff. It is our opinion that groundwater or surface drainage is not a limiting factor for this Project. 4.2 Erosion Hazards Based on the USCS description of the Project soils, the surface soils are considered moderately erodible. According to the Resource Map from the Washington State DNR, as provided above, the Project is not within terrain labeled `highly erodible.' This Project is near an erosion hazard area as defined by the MCRO. Erosion hazard areas are those with USDA SCS designations of River Wash (Ra), Coastal Beaches (Cg), Alderwood Gravelly Sandy Loam on slopes 15% or greater (Ac and Ad), Cloquallum Sift Loam on slopes 15% or greater (Cd), Harstine Gravelly Sandy Loam on slopes 15%or greater(Hb), and Kitsap Silt Loam on slopes 15%or greater(Kc). Development will occur away from Ac soils within areas where slopes are less than 15%. Due to this and the absence of other erosion hazards, development should not require a separate engineered erosion control plan. Temporary and/ or permanent erosion control measures are required for any site when land disturbance is involved. Erosion control will mostly depend on the timeliness of construction, moisture content of the soil,and amount of rainfall during construction. Soil erosion typical to the existing conditions and planned disturbance of this Project include wind-borne silts during dry weather, and sediment transport during prolonged wet weather. Sediment transport of disturbed soils could be from stormwater runoff or tracking off-site with construction equipment. Although an engineered erosion control plan is not warranted for this project, Best Management Practices (BMP's) should be employed during and after construction. Ordinary BMP's includes silt fencing,protection of drainage outlets and vegetating denuded areas. Erosion control information and specifications may be found in the applicable "Stormwater Management Manual for Western Washington,"prepared by the Washington State Department of Ecology Water Quality Program. 4.3 Seismic Hazards Soils immediately below the expected foundation depth for this Project are generally Type D, corresponding to the International Building Code (IBC) soil profiles. According to the IBC, the regional seismic zone is 3 for this Project. The estimated peak ground acceleration ranges from Envirotech Engineering Lincoln Geological Assessment Ph. 360-275-9374 pagc 9 Parcel 232232 50 80029 Fax: 360-275-4789 Mason County, Washington April 18, 2012 0.50g to 0.60g. This estimation is based on the United States Geological Survey(USGS)National Seismic Hazard Project in which there is an estimated 2% probability of exceedance within the next 50 years. There are no known faults beneath this Project. The nearest Class `A' or 'B' fault to this property is the Hood Canal fault zone.This fault is a Class `B` and is located less than 5 miles to the north west of the Project, and the Tacoma Fault Zone which is located approximately 10 miles to the east. This information is supported by the USGS Quaternary Fault and Fold Database for the United States. The potential for liquefaction and other earthquake induced hazards are believed to be low for this Project. This is based on subsurface conditions such as soil characteristics and the lack of a permanent and substantial shallow water table. Subgrade characteristics that particularly contribute to problems caused by seismic events include submerged and confined, poorly-graded granular soils. Although gravel- and silt-sized soil particles could be problematic, fine and medium grained sands are typically subjected to these types of seismic hazards. 4.4 Other Considerations Conclusions in this report are based on the type and location of the anticipated development, and existing surface and subsurface conditions. Site development that significantly deviates from the anticipated improvements presented in this report may require geotechnical design recommendations. Envirotech Engineering Lincoln Geological Assessment Ph. 360-275-9374 page 10 Parcel 232232 50 80029 Fax: 360-275-4789 Mason County, Washington April 18,2012 5.0 CLOSURE Based on the project information and site conditions as presented in this report, it is Envirotech's opinion that additional geotechnical studies are not required to further evaluate this Project. Due to the inherent natural variations of the soil stratification and the nature of the geotechnical subsurface exploration, there is always a possibility that soil conditions encountered during construction are different than those described in this report. Therefore, it is recommended that a qualified engineer observes and documents the construction, or Envirotech is promptly notified if project and subsurface conditions found on-site are not as presented in this report so that we can re-evaluate our recommendations. This report presents a geological/geotechnical assessment, and is intended only for the owner,or owners' representative. Furthermore, this report is only valid for the project information and location described herein. The services described in this report were prepared under the responsible charge of Michael Staten, a professional engineer with Envirotech. Michael Staten has appropriate education and experience in the field of geotechnical engineering in order to assess landslide hazards, earthquake hazards,and general soil mechanics. Please contact Michael Staten at 360-275-9374 if you have any questions, continents, or require additional information. Sincerely, Envirotel Engineering Michael Staten, P.E. Geotechnical Engineer Envirotech Engineering Lincoln Geological Assessment Ph. 360-275-9374 page i 1 Parcel 232232 50 80029 Fax: 360-275-4789 Mason County, Washington April 18,2012 APPENDIX A SITE PLAN 6 80 0 SCALE 1 INCH = 40 FEET 80 FT ± x, 0 5 10 20 40 E HALLER AVE 32232 50 80001 L7 z3 w RETAINING xx rY> WALL 100 w a TP143 SINGLE AMILY 4H RESIDENC 0 .D SEPTIC DRAINFIELD m 0 FF �4, PROPOSED GARAGE i i 32232 50 80029 0 0 80 FT ± SP v E' AV E PROJECT/ OWNER/ LOCATION SINGLE FAMILY PROPERTY GEOLOGICAL ASSESSMENT DON LINCOLN 81 E HALLER AVE PARCEL 32232 50 80029 MASON COUNTY WASHINGTON SITE PLAN SHOWS LEGEND ENGINEER, DEVELOPMENT WITHOUT EN BOX-9CH ENGINEERING THE BENEFIT OF A LAND SLOPE INDICATOR REELFFAIR9WASHINGTON 98528 SURVEY. SITE FEATURES 360-275-9374 ARE APPR❑XIMATE, I TPIO TEST PIT SITE PLAN APPENDIX B SOIL INFORMATION TEST PIT LOG TEST PIT NUMBER TP-1 PROJECT: SFR Geological Assessment DATE OF LOG: 04/10/2012 PROJECT NO: 1243 LOGGED BY: MCS CLIENT: Don Lincoln EXCAVATOR: N/A LOCATION: Parcel 32232 50 80029 DRILL RIG: None Mason County, Washington ELEVATION: N/A INITIAL DEPTH OF WATER: N/A FINAL DEPTH OF WATER: N/A SOIL STRATA, STANDARD PENETRATION TEST DEPTH SAMPLERS USCS DESCRIPTION LL PI CURVE AND TEST DATA DEPTH N 10 30 50 p ........................................ GM Brown, moist, medium dense SILTY GRAVEL with SAND. Gravel is course and subrounded. Sand is primarily 1 medium and coarse. Nonpiastic. 2 C Very dense'hardpan.' 3 4 Excavation terminated at approximately 4.0 feet 5 6 7 8 9 10 No Groundwater Encountered ENVIROTECH ENGINEERING This intormation pertains only to this boring and should not be Geotechnical Engineering interpreted as being indicithe of the entire site. Map Unit Description:Alderwood gravelly sandy loam,5 to 15 percent slopes— Mason County,Washington Mason County, Washington Ab—Alderwood gravelly sandy loam, 5 to 15 percent slopes Map Unit Setting Elevation: 50 to 800 feet Mean annual precipitation: 25 to 60 inches Mean annual air temperature:48 to 52 degrees F Frost-free period: 180 to 220 days Map Unit Composition Alderwood and similar soils: 100 percent Description of Alderwood Setting Landform: Moraines Parent material: Basal till with a component of volcanic ash Properties and qualities Slope: 5 to 15 percent Depth to restrictive feature: 24 to 32 inches to dense material Drainage class: Moderately well drained Capacity of the most limiting layer to transmit water(Ksat): Very low to moderately low(0.00 to 0.06 in/hr) Depth to water table:About 18 to 36 inches Frequency of flooding: None Frequency of ponding. None Available water capacity:Very low(about 2.5 inches) Interpretive groups Land capability(nonirrigated):4s Typical profile 0 to 10 inches.Gravelly sandy loam 10 to 28 inches:Very gravelly sandy loam 28 to 60 inches: Gravelly sandy loam Data Source Information Soil Survey Area: Mason County, Washington Survey Area Data: Version 6, Sep 22, 2009 Natural Resources Web Soil Survey 4/16/2012 Conservation Service National Cooperative Soil Survey Page 1 of 1 ` p Original end First Copy with WATER WELL REEPOOT Sal Card q0. 086255 Depa+ d daent Ecology Second Coo'—Owner's Copy STATE OF WASHINGTON Third Copy—O~•m CAPy Water Riots Pemrit tie. 40 a.. 0 (1) OWNER: Name Ed TFM—;nn Address CL (2) LOCATION OF WELL: Comfy Mason SE F %soc_32✓T_22N..RAeLw.M. (2s) STREET ADODRESS OF WELL(or leareat addrean) 431 Orre NnbleS Rd Uninn WA 9R592 3 (3) PROPOSED USE: 11 Domeelm Industrial ❑ Municipal!❑ (10) WELL LOG or ABANDONMENT PROCEDURE DESCRIPTION :3 Irrigation N ❑ Dewater Test WON ❑ Other ❑ Farnrtwh: Doerulbs by cola., ohararter, We of nh *"1 and slrudivis. and she. ejokseas of agoHers asd the kid and eaten of We material IN each etrdew PwnsbaMd. r (4) TYPE OF WORK:O.ahsr's mrfrba of cod wmh at k"con wiry lot each c usage of iMwraatlon. (if awe then am) '— �ypDa -- fa011 TO 0 Abandoned O New well ® Method: Dag ❑ Bored O Deepened ❑ Cable Drlval O — OReconditioned LARotary Jelled ❑ 0 (5) DIMENSIONS: inches. Milled-223—fiew. Dopthofoomptetedwell 225 ft. Sand & gravel E pC (6) CONSTRUC'nON DETAILS: Sand & ravel with some water 1 37 1 42 Coaling InstMled: �_' Dion.tom. -0 —It.to-220—h. womad DWM.from h.to R. Threaded Diem.true A-to—ft. i. Perforatlonm Yeso wlid Cemented sand &-gravel with wa-ter- 0 Type of perforator used �— SIZE of perforations ie.by co- la 00.fore llong from n.to h_ pe"Welionsfrom _fl.to M. Cemented sand & gravel with tfi perteratiean(rem tt.ke a. Screeae: Yu No Mmnteaclwer's Mesa—HOI'Q'-= TyPe stainless model Nogravel i with water Dm. It Sr h �0 v 0 n.to 275 „d CDiam slot size uom n.to—It. 2 Gmel picked: Yes No Size of sra.al s` SGravel placed hone ft.to It- SWINCe steel: Yee Ei No❑ To what depth, 18 ft. O Material rm w in atel RetoDite Z Did any strata contain unranble water? Yu❑ NoEi 4A Type of water? Ueeha of alreta S Nethed of seeing atrate off with W (7) PUMP: Manulsetmersmemo_ i [`t177i Type: Cilh_ i p--3— (B) WATER LEVELS: L�owlecee�� above bun ase legal R. o V Slane level 72 ft.below too of was Date W Arte sari pressure ms,per square inch Dale 1111-- Artesian wetw is e, ---Ne'by 0 Work Waned te. Cam Mfed 19- 4•+ (9) WELL TESTS: Dretrdy�t Ia aa�ytt w■ter lbw is lowed belowr steac k" urea m pa ilm ads?Yea No m yan,w m ate-P�0 97 WELL CONSTRUCTOR CERTIFICATION: View: got.tmia.with It.dasardoawallar�_tie. I cosstrucled and/or accept responalblNty for construction of INe brill, and its complienco with all Washington well construction ssslldirds. 30 Materials w ts Used sad I is(ormslioa reported above are true to my bed — knathdedq.and belief. os CL Recery dote(time taken as zero yttan pwup turned do(water Isy l mpmred all from trot roc a water lewq 0 _ Q 010 w153 I Too wa.t...r nn. w.t.rte I NAM Davis Drillinz �}� t tt (r•ER80N.ants.OR cQIpOaAflOu) RITE on PAurTf t 1 min 130 min RS )— 2 min 1Q5 9 min - 80 Addeass— Belfair WA 98528 Date of Iut 5,[2�/9 0 License Pro. 1884 (slorl.a) Better teat cal.tmirt.with ft.drawdotm affair tis- WE Carflractora nn Aslant gal.imip.with glee ell at e.for tire. Reg(d D 1100A ()at. M_ a=b 'tg-9.2 Arloehan Now g.p.m. Date . Temperatorsof water_ Was a chemical analysis made?Vas® No❑ (USE ADDITIONAL SHEETS IF NECESSARY) ECY060.1-20 110•8n -iws. -01W2 Mason County Review Checklist For a Geological Assessment Instructions: This checklist is intended to assist Staff in the review of a Geological Assessment. The Assessment is reviewed for completeness with respect to the Resource Ordinance. If an item is found to be not applicable, the report should explain the basis for the conclusion. The Assessment is also reviewed for clarity and consistency. If the drawings, discussion, or recommendations are not understandable, they should be clarified. If they do not appear internally consistent or consistent with the application or observations on site, this needs to be corrected or explained. If resolution is not achieved with the author, staff should refer the case to the Planning Manager or Director. Applicant's Name: �) I ,to'ge Permit#: �� l� 006L3 Parcel #'s: Date(s) of the Do�e4(s)tr�ieweoU 1. A discussion of geologic conditions in the general vicinity of the proposed development, with geologic unit designation basedreferenced maps. OK? Comment: 2. (a) A discussion o the ground water conditions at the site, OK? Comment: (b) A discussion of the estimated depth to water OK?(Z Comment: (c) A discussion f the quantity of surface seepage OK? Comment: (d) A discussion of the upslope geomorphology OK? Comment: (e) A discussion o location of upland waterbodies and wetlands. OK? Comment: 3. The approximate d pth to hard or dense competent soil, e.g. glacial till or outwash sand. OK? Comment: 6 4. A discussion of any geomorphic expression of past slope instability (presence of hummocky ground or ground cracks, terraced topography indicative of landslide block movement, bowed or arched trees indicating downslope movem t, etc.). OK? Comment: 5. A discussion of the history of landslide activity in the vicinity, as available in the referenced maps and records. OK?_ Comment: 6. An opinion on whether the proposed development is within the landslide hazard area or its associated buffer or setback and the potential for landslide activity at the site in light of the proposed development. OK? Comment: r 7. A recommendation by the preparer whether a Geotechnical Report should be required to further evaluate site conditions and th�'proposed development of the subject property. OK? Comment: N , �t Page 1 of 2 Form Effective June 2008 8. If the presence of a hazard is determined within 300 feet of the proposed development, then the following are delineated on a geologic map/site map: (a) the area of the proposed development, OK? Comment: (b) the boundaries of the landslide hazard area (top, both sides, and toe), OK? Comment: (c) the associated buffers (top, both sides, and toe) OK? Comment: (d) building or other setbacks (top, both sides, and toe). OK? Comment: 9. A site map drawn to scale showing the property boundaries, scale, north arrow, and the location and nature of existing and propospd development on the site. OK? Comment: Are the Documents signed and stamped? By whom? Sf�,E License#: �n(-f License type: 2 3 FIRST REVIEW If not approved, what is the next action/recommendation for further action? Reviewed by on . Time spent in review: SECOND REVIEW/ UPDATE Reviewed by on . Time spent in second review: THIRD REVIEW/ UPDATE Reviewed by on . Time spent in third review: Disclaimer: Mason County does not certify the quality of the work done in this Geological Assessment Page 2 of 2 Form Effective June 2008 VED ��R RECEI LA i N Jul. 2 5 2013 t►�' `' 'Aft ST Mason County Department of Community Development Submittal Checklist For a Geological Assessment Instructions: 6OQ3Z,,, This checklist must be submitted with a Geological Assessment and completed, signed, and Uw 3 f stamped by the licensed professional(s)who prepared the Geological Assessment 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 ,00n ZIncojh Parcel# 3Z237——50—900S9 Site Address �/ G 86-11&t- f-tyenue �.)Azo o �—F000l (1) A discussion of geologic conditions in the general vicinity of the proposed development, with geologic unit designation based on referenced maps. Located on page(s) S (2) (a)A discussion of the ground water conditions at the site, Located on page(s) 6 (b) A discussion of the estimated depth to water Located on page(s) 6 (c) A discussion of the quantity of surface seepage Located on page(s) 6 (d) A discussion of the upslope geomorphology Located on page(s) 3 (e) A discussion of location of upland waterbodies and wetlands. Located on page(s) _3 (3) The approximate depth tg hard or dense competent soil, e.g. glacial till or outwash sand. Located on page(s) b (4) A discussion of any geomorphic expression of past slope instability (presence of hummocky ground or ground cracks, terraced topography indicative of landslide block movement, bowed or arched trees indicating downslope movement, etc.). Located on page(s) 31 4� (5) A discussion of the history of landslide activity in the vicinity, as available in the referenced maps and records. Located on page(s) `7� 9 (6) An opinion on whether the proposed development is within the landslide hazard area or its associated buffer or setback and the potential for landslide activity at the site in light of the proposed development. Located on page(s) (7) A recommendation by the preparer whether a Geotechnical Report should be required to further evaluate site conditions and the proposed development of the subject property. Page 1 of 2 Form Effective June 2008 1 Located on page(s) (8) If the presence of a hazard is determined within 300 feet of the proposed development, then the following are delineated on a geologic map/site map: (a) the area of the proposed development, Located on Map(s) / (b) the boundaries of the l,',afj�� slide hazard area (top, both sides, and toe), 1U Located on Map(s) 4 (c) the associated buffers p, both sides, and toe) Located on Map(s) 2 (d) building or other set f 41� (top, both sides, and toe). Located on Map(s) (9) A site map drawn to scale showing the property boundaries, scale, north arrow, and the location and nature of existin and proposed development on the site. Located on Map(s) G I, "C404J 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 Geological Assessment, dated r 7� and entitled meets all the requirements of the Mason County Resource Ordinance, Landslide Hazard Section, is complete and true,that the assessment 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) �`rJONALG Disclaimer: Mason County does not certify the quality of the work done in this Geological Assessment. Page 2 of 2 Form Effective June 2008