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CRA19920069.PDF• CX-f- oz - ' IIII�IIII v Critical Areas %Zhecklist CRA19920069 Site Information Project Name: �`a.e Permit umber: �l� 7 Site Location: �-5 �� roperty Tax Account umber. 1 1— 0 a-c( )07 C 03 �r zh S 10 -7a Approximate Site Size (acres or square feet): Have you filled out a Critical Areas Checklist for a project on this site before? " General Site Conditions 1. Has the site been cleared or logged? % _ Date of most recent action: ? Soils / Topography 2. In the Snohomish County Soil Survey, what is the mapped soil type(s)? C---.�.�-r.Y-� 3. Describe the general site topography. Check all thatapply.�. Flat: less than 5 feet elevation change over entire site. Rolling. slopes on site generally less than 15% (a vertical rise of 10 feet over a horizontal distance of 66 feet.) Hilly: slopes present on site of more than 15% and less than 30%. ( a vertical rise of 10 feet of horizontal distance.) Steep: grades of greater than 30% present on site. Comments Hydrology/Vegetation 4. Site contains areas of year-round standing water: 5. Site contains areas of seasonal standing water: L o Approx. Depth: 6. Site is in the floodway 7 - floodplairi /Z-o, of a water course. 7. Site contains a creek or an area where water flows across the grounds surface? ows ��- are year-round? Flows are seasonal? caw--�- _; shrubs ; mixed 8. Site is primarily: forested ; meadow 9. Obvious wetland is present on site: o � 10. Wetland inventory or map indicates wetland present on site: 11. Critical Areas inventory or map indicates any Critical Area on site: w 890-199 City of Edmonds Critical Areas Checklist. The Critical Areas Checklist contained on this form -is to be filled out by any person preparing a Development Permit Application for the City of Edmonds prior to his/her submittal of a developmentpermit to the City. The purpose of the Checklist is to enable City staff to determine whether any potential Critical Areas are or may be present on the subject property. The information needed. to complete the Checklist should be easily available from observations of the site or data available at City Hall (Critical Areas inventories, maps, or soil surveys). An applicant, or his/her representative, must fill out the checklist, sign and date it, and submit it to the City. The City will review the checklist, make a precursory site visit, and make a determination of the subsequent steps necessary to complete a development permit application. nth a signed copy of this form, the applicant should also submit a vicinity map of the parcel with enough detail that City staff can find and identify the subject parcel(s). In addition, the applicant is encouraged to include any other pertinent information or studies in conjunction with this Checklist to assist staff in completing their preliminary assessment of the site. I have completed the attached Critical Area Checklist and attest that the answers provided are factual, to the best of my knowledge (fill out the appropriate column below). Owner / Applicant: Title Street Address Applicant Representative: Name Title Street Address s , G'_� op g- 0.)_ (_ _'. jo City, State, ZIP Phone City, State, ZIP Phone CAignature Date Signature Date 0 0 City of Edmonds Critical Areas Determination Applicant: Debrah & Thomas Falk I Determination #: CA-92-69 Project Name: Permit Number: F7 Site Location: 15910 75th Pl. W Property Tax Acct #: 5131-029-007-0003 Project Description: New Single Family Residence. Waiver Criteria (all criteria must be found to apply): xx There will be no alteration of the Critical Area or its required buffers; •, xx The development proposal will not impact the Critical Area in a manner contrary to the goals, purposes, objectives and requirements of the Critical Areas ordinance; xx The development proposal meets the minimum standards of the Critical Areas ordinance; xx The above findings are based on the following conditions of approval: 1. The applicant must follow the requirements of the Building Official for construction on steep slopes 2. The applicant must follow the requirements of the Engineering Division for erosion control Based on the above findings and conditions, the requirement for a Critical Areas Study associated with this development permit is hereby Waived, as authorized by Chapter 20.15B.150 (B) of the Edmonds Community Develo ment Code. Name Nig -mature Date •, Ft�-c CITY OF EDMONDS 250 - 5TH AVE. N. • EDMONDS, WA 98020 • (206) 771-0220 • FAX (206) 771-0221 COMMUNITY SERVICES DEPARTMENT Public Works • Planning . Parks and Recreation . Engineering May 28, 1992 Deborah and Thomas Falk f16105 N. Meadowdale Rd. Edmonds, Wash. 98026 Re: Critical Areas Checklist Dear Deborah and Thomas Falk: LAURA M. HALL MAYOR More information is needed before a Critical Areas Determination can be completed for the property located at 15910 75th Pl. W. I will need a survey plan including the topography contour lines, the location of the existing drainage water on the site, and a soils report by an Engineer with expertise in the Geotechnic field that describes the existing soils conditions on the site, and makes recommendations about where the best location for driveways and structures is on the site to maintain soil stability. The soils report should make a recommendation about what type of foundations should be provided considering the soil conditions, and how to accommodate runoff from new development and existing water on the site. I will need to have you submit a resume of the Engineer that you choose for the City's approval, and we will then need to draw up a three party contract between you, the City, and the Geotechnic Engineer. I have a copy of the contract available when you submit the resume. Please have the above information prepared and submitted to me for review. No decisions can be made on your project until this information is provided. You may contact me at 771-0220 if you have any questions about this matter. Sincerely, Ed Somers, Associate City Planner • Incorporated August 11, 1890 • Sister Cities International — Hekinan, Japan GtOTECH RECEIVED CONSULTANTS b JUN - 2 1992 a •13256 N.E. 20th St. (Northup Way), Suite 16 COMMUNITY SERVICES Bellevue, WA 98005 (206) 747-5618 (206) 343-7959 February 7, 1990 JN 89482 Bill and Diane Pielow 8716 - 185th Place Southwest Edmonds, Washington 98020 Subject: Geotechnical Engineering Study Meadowdale Lot near 75th Place West and Meadowdale Beach Road Edmonds, Washington Dear Mr. and Mrs. Pielow: We are pleased to present this geotechnical engineering report discussing how to found a single-family residence on your lot in the Meadowdale Area. The purpose of our work was to explore site conditions and provide earthwork and foundation design criteria. The work was authorized by your acceptance of our confirmation proposal dated December 5, 1990. The subsurface conditions of the proposed building site were explored with two test pits and two test borings. We found the site to be underlain by three to five feet of uncontrolled fill soils overlying sands and silty clayey soils. There was a highly fractured zone of silty clayey soils from about seven to about fifteen feet below existing grades. The home can utilize augercast pier foundations extending through the fractured material to the more competent underlying soils. The attached report contains the results of our study and recommendations. If there are any questions, or if we can be of further service, please contact us. Respectfully submitted, GEOTECH CONSULTANTS, INC. Mark K. Dodds, P.E. Senior Engineer • • GEOTECHNICAL ENGINEERING STUDY PIELOW MEADOWDALE LOT NEAR 75TH PLACE WEST AND MEADOWDALE BEACH ROAD EDMONDS, WASHINGTON This report represents the results of our geotechnical engineering study for the Pielow lot in the Meadowdale area of Edmonds, Washington. The property is the third lot northwest of the intersection of 75th Place West and Meadowdale Beach Road. The general location of the site is illustrated on the Vicinity Map, Plate 1. Based on preliminary plans furnished to us, we anticipate that a large single-family residence will be constructed on the site. We anticipate the home will be located on the upper portion of the lot, similar to the home to the north. Development of the property is in the preliminary planning stage, and therefore only conceptual development ideas were available to us. No site plan was provided for this study. SITE CONDITIONS SURFACE The site is located in the Meadowdale Area, south of the existing home at 15908 - 75th Place West, Edmonds, Washington. The site is basically cleared, and there is a gravel driveway down to the flatter portion of the lot. There is an old shed situated on this flat area. The property is rectangular, with approximate dimensions of 80 feet by 180 feet. The lot to the north is developed with a single-family residence. The lot to the south is covered with a growth of small to medium-sized trees and some shrubs. SUBSURFACE The subsurface conditions were explored by excavating two test pits and drilling two borings at the approximate locations shown on the Site Plan, Plate 2. The field exploration program was determined based upon the proposed use, site GEOTECH CONSULTANTS, INC. • Bill & Diane Pielow JN 89482 February 9, 1990 Page 2 • topography, subsurface conditions revealed during excavation and drilling, the scope of work outlined in our proposal, and time and budget constraints. The test pits were excavated on November 17, 1989 with a rubber -tired backhoe owned and operated by Evans Brothers Excavating. The borings were drilled on December 15, 1989, using a truck -mounted hollow stem auger drill owned and operated by Pearson Drilling. Samples were taken at five (5) foot intervals during drilling using a standard penetration sampler. This two-inch outside diameter split spoon sampler is driven into the soil with a one hundred forty (140) pound hammer falling thirty (30) inches. The number of blows required to advance the sampler a given distance is an indication of the soil density or consistency. A Shelby tube (thin -walled) sample was collected from Test Borings 1 and 2 from ten to twelve feet below existing grades. A geotechnical engineer from our staff observed the excavation and drilling process, logged the test pits and test borings, and obtained representative samples of the soils encountered. "Grab" samples of selected subsurface soils were collected from the backhoe bucket and auger cuttings. The Test Boring Logs are attached to this report as Plates 2 and 3. The Test Pit Logs are attached as Plates 4 and 5. Test Pit 1 was placed near the northwest corner of the flatter area. At this location there was five feet of sandy fill overlying silt to clayey silt. This silt layer became heavily fractured below 11.0 feet to the maximum extent of the backhoe reach at 12.5 feet below existing grades. Test Pit 2 was excavated near the southwest corner of the flatter area that happened to be cleared of blackberry brush. Test Pit 2 revealed three feet of sandy fill that had bricks and concrete in it, overlying seven feet of silty, very wet fill with sand lenses that had a lot of wood and railroad ties in it. From 10.0 to 13.5 feet, where Test Pit 2 was terminated, the subsurface consisted of a firm sandy silty soil. Test Boring 1 was placed about ten feet south of Test Pit 1. The surface at this location was underlain with 3.5 feet of loose sandy fill. Below the fill was 4.5 feet of loose to medium -dense gravelly silty sand. From 8.0 to about 9.5 feet a soft to firm wet sandy silt was encountered. At 9.5 feet a fractured to heavily fractured silty clay was encountered, and this fractured layer continued to about 15.0 feet. Below 17.0 feet the clay graded into competent silt which was very stiff to hard. GEOTECH CONSULTANTS, INC. • Bill & Diane Pielow JN 89482 February 9, 1990 Page 3 Test Boring 2 was drilled on the eastern side of the lot, in the middle of the driveway down to the property. At this location three feet of sandy fill underlain in turn by four feet of loose gravelly silty sand was below the driveway surface. From 7.0 feet to about 17.0 feet a plastic silty clay was encountered. This clay was fractured from seven feet to about 12 feet below existing grades. From 17.0 to 34.0 feet a very stiff to hard clayey silt layer was encountered. There were two one -inch -thick fracture zones noted at 33.0 feet. From 34.0 to 39.0 feet, where Test Boring 2 was terminated, a brown medium -dense to dense sand with some silt was encountered. The final logs represent our interpretations of the field logs and laboratory tests. The stratification lines on the logs represent the approximate boundary between soil types. In actuality, the transition may be gradual. The relative densities and moisture descriptions indicated on the test pit and boring logs are interpretative descriptions based on the conditions observed during the excavation. The logs should be reviewed for specific subsurface information at the locations tested. Is GROUNDWATER • Heavy groundwater seepage was observed in the test pits at a depth of three to eight feet below existing grades. The test pits and borings were left open only for a short time period, therefore, the seepage levels on the logs represent the location of transient water seepage and may not be the location of the static groundwater level. It should be noted that groundwater levels vary seasonally with rainfall and other factors. We anticipate that groundwater could be found between the near surface weathered soil and the underlying denser soils and in the fracture zones in the silts and clays. LABORATORY TESTING Samples collected during our field work were reviewed in the office, and selected samples were subjected to laboratory testing. Index tests of the samples included moisture contents, sieves, and Atterberg Limits. One Shelby Tube sample was subjected to a multiple -stage Triaxial Shear Test. The results of the laboratory testing are appended to this report. GEOTECH CONSULTANTS, INC. • Bill & Diane Pielow February 9, 1990 CONCLUSIONS AND RECOMMENDATIONS GENERAL JN 89482 Page 4 The lot is underlain by a heavily fractured zone of silt and clay from about seven to fifteen feet below existing grades. This fractured material has some residual strength, as evidenced by the multiple -stage triaxial shear test. There appears to have been an old ravine running east -west along the southern property boundary. We estimate that there is five to fifteen feet of fill along this boundary. The construction of a single-family residence on the lot appears feasible from a geotechnical engineering perspective. The structure will have to utilize heavily -reinforced deep foundations which extend through the fractured silt/clay layer and any fill soils. We recommend that minimum sixteen -inch - diameter piers be utilized for the residence. The final grades for the lot should be near existing grades, and only minor amounts of filling and/or cutting should be planned. It is also important to adequately design for the control of 30- the surface and subsurface groundwater flows. Control measures must be in place both during and after construction of the home. The Meadowdale area has been identified as an old landslide area. The entire neighborhood is at risk if even a moderate earthquake event occurs in the immediate area. It is our opinion that this lot, if developed in accordance with the recommendations herein, will result in a structure that is as stable as any in the neighborhood. Geotech Consultants Inc. should be given the opportunity to review the plans and specifications as they are developed to verify site specific subsurface requirements are met. FOUNDATIONS The structure should be supported on minimum sixteen -inch - diameter steel -reinforced augercast piers. Augercast piers should be installed with continuous flight hollow -stem auger equipment. This method involves the pumping of concrete through the hollow -stem auger equipment during extraction of the auger. Concrete grout must be pumped continuously through the auger as it is withdrawn. The rate of withdrawal should not exceed nine feet per minute. The grout pressure at the • GEOTECH CONSULTANTS. INC. • Bill & Diane Pielow JN 89482 February 9, 1990 Page 5 • grout pump should be in the range of 150 to 250 psi, depending on the length of feeder hose used. The pump should be equipped with a calibrated stroke counter so that grout volumes may be calculated. For a sixteen (16) inch diameter pier with a minimum of fifteen feet of penetration into the competent native soils below the fracture zone, an allowable capacity of fifteen (15) tons may be assumed. Piers should be placed no closer than three pier diameters, center to center. For wind or seismic loads, the allowable load can be increased by one-third. We can provide design criteria for different pier diameters and embedment lengths if greater capacities are required. Based on our field work, we estimate total pier lengths of thirty to forty feet will be required to assure adequate penetration into the bearing soil. Piers should be reinforced their entire length with steel H beams or large re -bar cages. The piers should be designed to withstand an active pressure of seventy (70) pounds per cubic foot (pcf) acting over the top fifteen (15) feet of the pier. Below this depth, the overturning pressures are resisted by passive pressures acting over two times the pier diameter. The passive pressures can be assumed to be three hundred (300) pcf. . We estimate that total settlement of single piers will be on the order of one-half inch. Most of this settlement should occur during construction as the dead loads are applied. We estimate differential settlements over the structure should be less than one-half inch. Lateral pier capacity is generally governed by deflections at the top of the pier which depend on the pier stiffness with respect to the surrounding soil near the upper portion of the pier, the length of the pier, and the degree of fixity at the pier cap. We can provide lateral capacities of piers once design plans are prepared. Geotech Consultants Inc. personnel should be on -site to observe augercast pier installation. As the completed piers below ground cannot be observed and tested, it is important to have a qualified person on site who can decide when the piers are deep enough and will understand the impacts of contractor variance from the specifications. GEOTECH CONSULTANTS, INC.. • Bill & Diane Pielow February 9, 1990 • SLAB -ON -GRADE FLOORS JN 89482 Page 6 Slab -on -grade floors may be supported on undisturbed competent -- native soils or on structural fill. The slab should also be provided with a minimum of four (4) inches of free draining sand or gravel. In areas where moisture is undesirable, a vapor barrier such as a 6-mil plastic membrane should be placed beneath the slab. PERMANENT RETAINING AND FOUNDATION WALLS Retaining and foundation walls should be designed to resist the lateral earth pressures imposed by the retained soils. We anticipate that only small walls will be used on this site. The following recommendations are for walls of limited height which restrain level backfill: Design Parameter Value Active Earth Pressure* 50 pcf Passive Earth Pressure 250 pcf Soil Unit Weight 120 pcf Where: 1) pcf is pounds per cubic foot. 2) Active and Passive Earth Pressures are computed using equivalent fluid densities. k For restrained walls which cannot deflect at least 0.002 times the wall height, a uniform lateral pressure of one hundred (100) psf should be added to the active equivalent fluid pressure. The values given above are ultimate values. An appropriate safety factor should be applied when designing the walls. We recommend using a minimum factor of safety of 1.5 for overturning and sliding. The resultant force, which can be determined by taking moments about the toe of the wall while neglecting the passive pressure force, should pass through the middle third of the footing. GEOTECH CONSULTANTS, INC. • Bill & Diane Pielow JN 89482 February 9, 1990 Page 7 The above design values also do not include the effects of any hydrostatic pressures behind the walls and assume that no surcharge slopes or loads will be placed above the walls. In addition, construction equipment should not operate within a prism defined by a 1:1 (Horizontal:Vertical) line extending from the back end of the footing to the retained soil behind the structure. If these conditions exist, then those pressures should be added to the above lateral pressures. Also, if sloping backfill is desired behind the walls, then we will need to be given the wall dimensions and slope of -the backfill in order to provide the appropriate design earth pressures. Retaining and foundation walls should be backfilled with compacted free -draining granular soils containing no organics. The wall backfill should contain no more than 5 percent silt or clay and no particles greater than four inches in diameter. The percentage of particles passing the No. 4 sieve should be between 25 and 70 percent. Compaction of backfill behind the retaining wall should utilize methods which will not damage the wall. The purpose of the backfill requirements is to assure that the design criteria for the retaining wall is not exceeded because of a build-up of hydrostatic pressure behind the wall. Where the backfill is to support walks or other slabs, we recommend that the backfill consist of clean sand and gravel as this soil would be easier to compact in the excavation prism than siltier soils. Also, these soils will provide drainage behind the wall. The top foot to eighteen inches of the backfill should consist of a relatively impermeable soil or topsoil, or the surface should be paved. SITE DRAINAGE We recommend the use of footing drains at the base of all footings and earth retaining walls. Roof and surface water drains must be kept separate from the foundation drain system. The footing drains should be surrounded by at least six inches of one -inch -minus washed rock. The rock should be wrapped with non -woven geotextile filter fabric (Mirafi 140N, Supac 4NP, or similar material). At the highest point, the perfor- ated pipe invert should be at least as low as the bottom of the footing and/or crawl space and it should be sloped for drainage. A typical footing drain detail is attached to this report as Plate 6. All drains should discharge to a suitable discharge facility, or be tightlined to the bottom of the slope. GEOTECH CONSULTANTS, INC. • Bill & Diane Pielow JN 89482 February 9, 1990 Page 8 • The excavation and site should be graded so that surface water is directed off the site and away from the tops of slopes. Water should not be allowed to stand in any area where buildings, slabs, or pavements are to be constructed. During construction, loose surfaces should be sealed at night by compacting the surface soils to reduce the infiltration of rain into the soils. The slopes should be covered with plastic. Final site grading in areas adjacent to buildings should be sloped at least two percent away from the building, except where the area adjacent to the building is paved. Groundwater was observed during the excavation of the test pits. Seepage into a foundation excavation is possible, and if encountered, the water should be drained away from the site by use of drainage ditches, perforated pipe or French drains, or by pumping from sumps interconnected by shallow connector trenches at the bottom of the excavation. EXCAVATIONS AND SLOPES In no case should excavation slopes be steeper or greater than the limits specified in local, state, and national government safety regulations. Temporary cuts to a depth of four feet in unsaturated soils may be attempted vertical. For slopes having a height greater than four (4) feet, the cut should have an inclination no steeper than 1.5:1 (Horizontal:Vertical) from the top of the slope to the bottom of the excavation. It should be noted that excavated slopes often cave suddenly and without warning. Utility contractors should be made especially aware of this potential danger. All permanent cut slopes into the native soils should be inclined no steeper than 3:1 (H:V). Fill slopes should also not exceed 3:1 (H:V). Water should not be allowed to flow uncontrolled over the top of any slope. Also, all permanently exposed slopes should be seeded with an appropriate species of vegetation to reduce erosion and improve stability of the surficial layer of soil. SITE PREPARATION AND GENERAL EARTHWORK We recommend that the building and pavement areas be stripped and cleared of all surface vegetation, all organic matter, existing fills, and any other deleterious material. Stripped materials should be removed from the site or, if desired, stockpiled for later use in landscaping. The stripped GEOTECH CONSULTANTS, INC. • Bill & Diane Pielow February 9, 1990 JN 89482 Page 9 materials should not be mixed with any materials to be used as structural fill. Structural fill is defined as any fill placed under buildings, pavements, walkways, or other areas where the underlying soils need to support loads. Geotech Consultants, Inc. should observe site conditions prior to fill placement. The surficial site soils are moisture -sensitive and can become soft when wet and disturbed. We recommend that, if possible, the site preparation and earthwork be performed in the normally dry season of the year when earthwork would generally be less expensive and require less effort. Structural fill under floor slabs should be placed in horizontal lifts and compacted to a density equal to or greater than 95 percent of the maximum dry density in accordance with ASTM Test Designation D-1557-78 (Modified Proctor). The fill materials should be placed at or near the optimum moisture content. Fill under pavements and walks and behind retaining walls should also be placed in horizontal lifts and compacted to 90 percent of the maximum density except for the top twelve (12) inches which should be compacted to 95 percent of maximum density. The allowable thickness of the fill lift will depend on the material type, compaction equipment and the number of passes made to compact the lift. In no case should the lifts exceed eight (8) inches in loose thickness. Ideally, structural fill which is to be placed in wet weather should consist of a granular soil having no more than 5 percent material passing the No. 200 sieve. The percentage of particles passing the 200 sieve should be measured on that portion of the soil passing the three-quarter inch sieve. The on -site soils should not be used as structural fill. These soils are fine-grained and highly sensitive to changes in moisture and to disturbance. LIMITATIONS The analyses, conclusions and recommendations contained in this report are based on site conditions as they existed at the time of our exploration and assume that the soils encountered in the test borings and test pits are representative of the subsurface conditions of the site. If, during construction, subsurface conditions are found which are significantly different from those observed in the borings and GEOTECH CONSULTANTS, INC. GEOTECH CONSULTANTS i !> iuT vi • � sw .� reSrH v� sw PL SW S` x ,k_ , 49TH PL` x�s 3 q U ,dc VICINITY MAP Lot South of 15908-75th PI. West Edmonds, Washington Job No. Dote: N.T.S. Note: 89482 2/90 1 • 0 xe �o`g�o`ec �o�Q0`o4y` cP 0 5 L ' ©�% 31.31 21 7 36.31 31 11 15 35.9 4 21 23.3 5 34 20 BORING 1 Etevotion: -15' * USCS Description Depth Dark brown silty gravelly SAND, wet, loose (Fill) 311 Brown gravelly silty SAND, medium to coarse sand, Z wet, loose to medium dense SM. M L Gray sandy SILT, wet, soft to firm 8' / Gray silty CLAY, fractured, very moist, medium - CH stiff 27.5 6 31 ML' 25 27.7 7 44 30 35 40 " I I I' Gray clayey SILT, moist Very stiff to hard 162-' 29' .Test boring terminated at 29 feet on 12/15/90. No groundwater observed while drilling. *Estimated elevation below road. GEOTECH CONSULTANTS A TEST BORING LOG LOT SOUTH OF 15908 — 75TH PL. W. EDMONDS, WASHINGTON J06 No. Dole: Lopped ey+ + 89482 12 15 89 MKD 2 • "40 2e 's .14 �p g°41 4d uscs 0 5 10 15 • 20 25 30 qb 35 BORING 2 Description E/evolion� -7'. Deplh Dark brown silty gravelly SAND, wet, loose (Fill) GSM 16.0 1 6 Brown gravelly silty SAND, moist, loose 40 Test boring terminated at 39 feet on 12/15/89. No groundwater observed while drilling. GEOTECH CONSULTANTS A TEST BORING LOG LOT SOUTH OF 15908 - 75TH PL. W. EDMONDS, WASHINGTON 3 ' I Job No. Dote Lopped er: PYoff 89482 1 12/15/89 1 MKD 3 ova 0 G°� USCS 0 3 10 15 20 E-1 • TEST PIT 1 Eievotion-15' --20' * Description Brown gravelly silty SAND with occasional cobbles, wet, loose Less silt below 2 feet Gray SILT to clayey silt, wet, firm with pieces of wood and rocks Gray -green silty CLAY, wet, firm to medium stiff Heavily fractured below 11 feet Test pit terminated at 122 feet below existing grade. Moderate to heavy groundwater seepage encountered at 3 feet bduring excavation. Heavy caving 5 to 7 feet. *Estimated elevation below 75th Place West. GEOTECH CONSULTANTS TEST PIT LOG LOT SOUTH OF 15908 — 75TH PL. W. EDMONDS, WASHINGTON ✓ob No. 8949 Dole' Copped By Pio/e 4 1 \ 0\0\ to i 0eQ�r G USCS 0 • 5 TEST PIT 2 E/e OHOO�l 5' Description Brown gravelly silty SAND with roots, concrete, bricks, wood, wet, loose (Fill) Gray sandy clayey SILT with numerous railroad ties, very wet, soft (Fill) Gravelly medium sand layer 42 to 5 feet 10 — — Gray sandy clayey SILT, wet, firm, with some roots ML 15 Test pit terminated at 132 feet below existing grade. Heavy groundwater seepage encountered at 3 to 8 feet during excavation. Heavy caving above 8 feet. 99 GEOTECH CONSULTANTS TEST PIT LOG LOT SOUTH OF 15908 — 75TH PL. W. EDMONDS, WASHINGTON .lob No.: Dale, Lopped By: Rope+ 89482 1 12 15 89 1 MKD 5 Slope bockfill away from foundation. —� BACKF/L L See text for requirements. WASHED ROCK 6 min. ' • o •. NONWOVEN GEOTEXT/LE FILTER FABRIC GEOTECH CONSULTANTS J TIGHTL /NE ROOF DRAIN Do not connect fo looting drain. VAPOR BARB/ER SLAB 4 min. i _r FREE - DRAINING SAND/GRAVEL 4" PERFORATED HARD PVC PIPE Invert at least as low as fooling and/or craw/ space. Slope to drain. Place weepholes downward. FOOTING DRAIN LOT SOUTH OF 15908 - 75TH PL. W. EDMONDS, WASHINGTON ✓00 NO. + Dolt+ Sto/t+ 89482 DEC 1989 N.T.S. :7 0 • 1111111111111111111111111 IIIIIIillllllllllllllllll U Bill & Diane Pielow JN 89482 February 9, 1990 Page 10 test pits, or assumed to exist on the lot, we should be advised at once so that we can review these conditions and reconsider our recommendations where necessary. Unanticipated soil conditions are commonly encountered on construction sites and cannot be fully anticipated by merely taking soil samples in borings or test pits. Such unexpected conditions frequently require that additional expenditures be made to attain a properly constructed project. It is recommended that the owner consider providing a contingency fund to accommodate such potential extra costs and risks. This report has been prepared for specific application to this project and for the exclusive use of Mr. and Mrs. Pielow and their representatives. Our recommendations and conclusions are based on the site materials observed, selective laboratory testing and engineering analyses. The conclusions and recommendations are professional opinions derived in accordance with current standards of practice within the scope of our services and within budget and time constraints. No warranty is expressed or implied. The scope of our services does not include services related to construction safety precautions and our recommendations are not intended to direct the contractor's methods, techniques, sequences or procedures, except as specifically described in our report for consideration in design. We recommend that this report, in its entirety, be included in the project contract documents for the information of the contractor. ADDITIONAL SERVICES It is recommended that Geotech Consultants, Inc. provide a general review of the geotechnical aspects of the final design and specifications to verify that the earthwork and foundation recommendations have been properly interpreted and implemented in the design and project specifications. It is also recommended that Geotech Consultants, Inc. be retained to provide geotechnical consultation, testing, and observation services during construction. This is to confirm that subsurface conditions are consistent with those indicated by our exploration, to evaluate whether earthwork and foundation construction activities comply with the intent of contract plans and specifications, and to provide recommendations for design changes in the event subsurface conditions differ from those anticipated prior to the start of construction. However, our work will not include supervision or direction of the actual work of the contractor, his GEOTECH CONSULTANTS, INC. Bill & Diane Pielow February 9, 1990 JN 89482 Page 11 employees or agents. Also, job and site safety, and dimensional measurements, will be the responsibility of the contractor. The following plates are attached and complete this report: Plate 1 vicinity Map Plates 2 - 3 Test Boring Logs Plates 4 - 5 Test Pit Logs Plate 6 Footing Drain Detail Plate 7 Triaxial Shear Results Respectfully submitted, oF GEOTECH CONSULTANTS, INC. • i Mark K. Dodds, P.E. S, •° %%.4'JSTESenior En ineer 0 aE.•f g ames R. Finley, Jr. P.E. Principal Attachments MKD/JRF:cvb • GEOTECH CONSULTANTS, INC.