Loading...
HomeMy WebLinkAboutLUA 09-033_Talbot Ridge Estates_F.• ···.'6 GEOTECHNICAL ENGINEERING STUDY PROPOSED 33-LOT RESIDENTIAL DEVELOPMENT SW CORNER AT SE 192ND ST. & I02NP AVE. SE KING COUNTY, WASHINGTON G-1992 Prepared for Mr. Cliff Williams Belmont Homes, Inc. P.O. Box 2401 Kirkland, WA 98083-2401 March 17, 2005 GEO GROUP NORTHWEST, INC. 13240 NE 20th Street, Suite 10 Bellevue, Washington 98005 Phone: ( 425) 649-8757 Email: info@geogroupnw.com Exhibit No. _ _,\,_\"----- Item No. L~5Ps>~~"3:: Received \ 0 0 ~ ~~3: King County Hearing Examiner 00~1;;}!@@ KC. D.D.E.S. ,1 ' . ' March 17, 2005 Mr. Cliff Williams Belmont Homes, Inc. P.O. Box 2401 Kirkland, WA 98083-2401 SUBJECT: GEOTECHNICAL ENGINEERING STUDY PROPOSED 33-LOT RESIDENTIAL DEVELOPMENT SW CORNER AT SE 192ND ST. & 102ND A VE. SE KING COUNTY, WASHINGTON Dear Mr. Williams: Geotechnlcal Engineers, Geologists & Environmental Scientists G-1992 Geo Group Northwest, Inc. has completed an investigation of subsurface soils at the above referenced site in King County, Washington. This work was performed in accordance with our proposal to you dated February 28, 2005. Geo Group Northwest, Inc., explored subsurface soil conditions at the site by excavating ten exploratory test pits on March 9, 2005. Soils encountered in the test pits consisted ofloose silty SAND and gravelly silty SAND with some cobbles overlying dense to very dense silty SAND and gravelly silty SAND with some cobbles at depths ranging from two to three feet below ground surface (bgs ). Based on the results of our study, it is our professional opinion that the site is geotechnically suitable for the proposed development. The proposed buildings can be supported on conventional spread footings bearing on the dense native site soils or on compacted structural fill placed on top of the dense native soils: The loose site soils and fills are not suitable to support foundations due to their loose and variable condition. Based on the findings from our soil investigation at the site, we anticipate that the dense soil under the building areas are present between 2 and 3 feet below ground surface (bgs ). Please refer to the text of the report for more specific recommendations regarding the site development. We appreciate this opportunity to have been of service to you on this project. We look forward . to working with you as this project progresses. Should you have any questions regarding this report or need additional consultation, please feel free to call us. 13240 NE 20th Street, Suite 10 Benevue, Washington 98005 Phone 425/649-8757 FAX 425/649-8758 March 17, 2005 Proposed 33-Lot Residential Development, King County, Washington Sincerely, Geo Group Northwest, Inc. William Chang, P.E. Principal Geo Group Northwest, Inc. G-1992 Page ii TABLE OF CONTENTS JOB NO. G-1992 Page 1.0 INTRODUCTION ...................................................... 1 1.1 Project Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Scope of Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2.0 SITE CONDITIONS ......................................... , .......... 2 2.1 Site Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2.2 Geologic Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2.3 Field Investigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.4 Soil Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.5 Groundwater Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3.0 SEISMIC CONSIDERATIONS ........................................... 4 4.0 STEEP SLOPE EVALUATION ........................................... 4 5.0 CONCLUSIONS AND RECOMMENDATIONS ............................. 5 5.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 5.2 Site Preparation and General Earthwork . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 5.2.1 Temporary Excavation and Slopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 5.2.2 Structural Fill ............................ ; . . . . . . . . . . . . . . . . . . 6 5.3 Spread Footing Foundations ......................................... "l 5.4 Permanent Basement and Conventional Retaining Walls ................... 9 5.5 Slab-on-Grade Floors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 5.6 Footing Drains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.7 Pavements ...................................................... 11 6.0 LIMITATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 7.0 ADDITIONAL SERVICES............................................. 12 ILLUSTRATIONS Plate 1 Plate 2 Plate 3 APPENDIXA: -Site Vicinity -Site Plan -Typical Footing Drain Detail TEST PIT LOGS AND SOIL LEGEND Geo Group Northwest, Inc. GEOTECHNICAL ENGINEERING STUDY PROPOSED 33-LOT RESIDENTIAL DEVELOPMENT SW CORNER AT SE 192ND ST. & 102ND A VE. SE KING COUNTY, WASIDNGTON G-1992 1.0 INTRODUCTION 1.1 Project Description The project site is located at the southwestern comer of the intersection at SE 192°• Street and 102°• Avenue SE in King County, Washington. The site is near the city limits for Renton, Washington. The project site consists of a 4.36 acre undeveloped parcel. We have been provided with a Conceptual Site Plan for the proposed development by Core Design which is dated December 17, 2004. According to the site plan the development will consist of33 new residential lots, as shown on Plate 2 · Site Plan. Finish floor elevations for the new buildings were not provided at the time of this study. An access road and cul-de-sac turnaround are planned to be located near the center of the lot, running east and west off of 102°• Avenue SE. We understand that a detention vault is planned for the northwestern comer of the project parcel with excavations on the order of 10 to 12 feet below existing grade. 1.2 Scope of Services The tasks we completed for this study were conducted in general accordance with the scope of work presented in our proposal dated February 28, 2005. The scope of work included the following: 1. Field exploration with ten test pits; 2. Preparation of test pit logs containing subsurface soil and groundwater observations; 3. . Preparation of a written geotechnical report with the following recommendations: o Allowable soil bearing capacity and foundation design criteria; o Slab-on-grade floors and capillary break; Geo Group Northwest, Inc. March 17, 2005 Proposed 33-Lot Residential Development, King County, Washington o Excavations, including temporary cut slope recommendations; o Grading and earthwork; o Drainage recommendations o Seismic design criteria o Earthwork and design recommendations for detention vault construction. G-1992 Page 2 The results of our subsurface investigation and our recommendations regarding the proposed development are summarized in the following report. 2.0 SITE CONDITIONS 2.1 Site Description We have been provided with a Conceptual Site Plan for the proposed development by Core Design which is dated December 17, 2004. We understand that the topography shown on the plan and incorporated into Plate 2 -Site Plan of this report is based upon lidar data and is therefore only an approximate representation of slope conditions. Based upon the site plan the site consists of gentle to steep west-facing slopes. According to the site plan the parcel ranges in elevation from approximately 408 feet at the east property line to 3 26 feet at the west property line. The majority of the site consists of gentle to moderate west-facing slupes. Moderate to steep slopes west-facing slopes with inclinations of36 to 40 percent are located at the northwestern comer of the project parcel. The site is currently undeveloped and highly vegetated by grass, blackberry bushes, fems, and trees. The trees at the site consist of primarily deciduous trees with a few mature evergreens located on the northern margins of the site. 2.2 Geologic Overview According to the Geologic Map of the Renton Quadrangle, King County. Washington, by Mullineaux, dated 1965, the surficial geology in the site vicinity is mapped as Ground Moraine Deposits (Qgt). The ground moraine deposits consist of glacial till soils which are generally described as an over-consolidated mixture of sand, silt and gravel which was deposited during the Pleistocene Fraser Glaciation period about 14,000 years ago. Geo Group Northwest, Inc. March 17, 2005 Proposed 33-Lot Residential Development, King County, Washington G-1992 Page 3 2.3 Field Investigation Geo Group Northwest, Inc., explored subsurface soil conditions at the site by excavating and logging ten exploratory test pits TP-1 through TP-10 on March 9, 2005. The test pits were spaced relatively equidistant across the site, as shown on Plate 2 -Site Plan. The test pits were excavated to \fepths ranging between 5 and 11 feet below ground surface (bgs ). Soil samples at varying depths were collected, classified and returned to our laboratory for moisture testing. The test pits were then backfilled with the excavated site soils and tamped into place by the excavator bucket. 2.4 Soil Conditions Soils encountered in the test pits consisted of loose silty SAND and gravelly silty SAND with some cobbles overlying dense to very dense silty SAND and gravelly silty SAND with some cobbles at depths ranging from two to three feet below ground surface (bgs ). We interpret the dense silty SAND and gravelly silty SAND with some cobble soils to be the ground moraine deposits, glacial till, discussed in the geologic literature. The following table summarizes the depth to dense site soils at each test pit location: Test Pit Number Project Area Depth to dense native soil (ft\ TP-1 Southeast 3 TP-2 Southeast 2.5 TP-3 Southwest 3 TP-4 Southwest 2.5 TP-5 West 2.5 TP-6 Northwest 2.5 .TP-7 Northwest 2 TP-8 Center 2 Geo Group Northwest, Inc. March 17, 2005 Proposed 33-Lot Residential Development, King County, Washington TP-9 Northeast TP-10 Northeast Copies of the Test Pit Logs are presenied in Appendix A: Test Pit Logs. 2.5 Groundwater Conditions < 3 3 G-1992 Page4 No groundwater seepage was encountered in the test pits. It should be noted that groundwater conditions may fluctuate seasonally, depending on rainfall, surface runoff and other factors. 3.0 Seismic Considerations Based upon our subsurface investigation at the site, it is our opinion that the project buildings may be designed using the Class C soil profile from the 2003 International Building Code, Section 1615.1.5. It is our opinion that the soils at the project site are not susceptible to liquefaction, due to the absence of groundwater within the loose soil zone. 4.0 Steep Slope Evaluation Based upon the site plan and our site reconnaissance moderate to steep west-facing slopes are located at the northwestern corner of the project site. Based upon the site plan the slopes have an inclination ranging from 36 to 40 percent from the horizontal. The slopes at the northwestern corner of the site are vegetated primarily by deciduous trees, ferns and bushes. At the time of our site visit the ground was covered with a large amount ofleaves and forest floor detritus. We observed no signs of soil movement at the northwestern comer of the site, such as scarps or slumps. Based upon our site reconnaissance and the soils encountered in out subsurface investigation, the moderate to steep slopes located a the northwestern comer of the site appear to be relatively stable in their present condition. Preliminary plans indicate that a detention vault will be located at the moderate to steep slopes at the northwestern corner of the site. We understand that the detention vault may require excavations of between 10 and 12 feet below ground surface. The primary concern with regard to locating the detention vault in the moderate to steep slope area is that temporary excavation slopes be excavated in accordance with this report. Excavation slopes in the overlying loose Geo Group Northwest, Inc. March 17, 2005 Proposed 33-Lot Residential Development, King County, Washington G-1992 Page 5 soils may be sloped no steeper than I H: IV. Excavations in the underlying dense soils may be sloped no steeper than 1H:2V. If groundwater seepage is encountered Geo Group Northwest, Inc. should be contacted to evaluate the stability of the excavation slopes. It is our opinion that the proposed detention vault may be located on the moderate to steep inclination slopes. Appropriate erosion control measures such as silt fences and plastic sheeting should be implemented during construction to prevent sediment laden runoff from being transported out of the work area. In addition, we recommend that permanent erosion control on.the moderate to steep angle slopes should consist of jute netting and slope stabilizing vegetation. 5.0 CONCLUSIONS AND RECOMMENDATIONS 5.1 General Based upon the results of our study, it is our professional opinion that the site is geotechnically suitable for the proposed development. The proposed buildings and detention vault may be supported on conventional spread footings bearing on the dense native site soils or on compacted structural fill placed on top of the dense native site soils. The overlying loose site soils are not suitable to support foundations. We anticipate that the dense soils are located at depths ranging from 2 to 3 feet below ground surface. Consequently we anticipate that a minimal amount of over-excavation may be required for the foundation at the building locations. 5.2 Site Preparation and General Earthwork The building pad areas should be stripped and cleared of surface vegetation and forest duff soils. Silt fences should be installed around areas disturbed by construction activity to prevent sediment-laden surface runoff from being discharged off-site. Exposed soils that are subject to erosion should be compacted and covered with plastic sheeting. 5.2.1 Temporary Excavation and Slopes Under no circumstances should temporary excavation slopes be greater than the limits specified in local, state and national government safety regulations. Temporary cuts greater than four feet in height should be sloped at an inclination no steeper than lH:l V (Horizontal:Vertical) in the loose site soils. Temporary cuts in the dense site soils may be excavated no steeper than IH:2V provided that no seepage is encountered. If groundwater seepage is encountered during Geo Group Northwest, Inc. r March 17, 2005 Proposed 33-Lot Residential Development, King County, Washington G-1992 Page 6 construction, excavation of cut slopes should be halted and the cut slopes should be re-evaluated by Geo Group Northwest, Inc. Permanent cut and fill slopes at the site should be inclined no steeper than 2H: IV. Surface runoff should not be allowed tci flow uncontrolled over the top of slopes into the excavated area. During wet weather exposed cut slopes should be covered with plastic sheeting during construction to minimize erosion. 5.2.2 Structural Fill All fill material used to achieve design site elevations below the building areas and below non- structurally supported slabs, parking lots, sidewalks, driveways, and patios, should meet the requirements for structural fill. During wet weather conditions, material to be used as structural fill should have the following specifications: I. Be free draining, granular material containing no more than five ( 5) percent fines ( silt and clay-size particles passing the No. 200 mesh sieve); 2. Be free of organic material and other deleterious substances, such as construction debris and garbage; 3. Have a maximum size of three (3) inches in diameter. All fill material should be placed at or near the optimum moisture content. The optimum moisture content is the water content in soil that enables the soil to be compacted to the highest dry density for a given compaction effort. The majority of the surficial site soils will be moisture-sensitive because they consist of silty SAND and gravelly silty SAND soils. The site soils should be suitable for use as structural fill as long as they are placed near their optimum moisture content. If these soils are too wet they will be very difficult to compact because of their silt content. Alternatively, an imported granular fill material may provide more uniformity and be easier to compact to the required structural fill specification. Geo Group Northwest, Inc. r March 17, 2005 Proposed 33-Lot Residential Development, King County, Washington G-1992 Page 7 If the on-site soils are to be used as engineered structural fill, it will be necessary to segregate the topsoil and any other organic-or debris-containing soil, because such soils would be unsuitable for use as structural fill. Excavated on-site material that is stockpiled for later use as structural fill should be protected from rainfall or contamination with unsuitable materials by covering it with plastic sheeting until it is used. · Structural fill should be placed in thin horizontal lifts not exceeding ten inches in loose thickness. Structural fill under building areas (including foundation and slab areas), should be compacted to at least 95 percent of the maximum dry density, as determined by ASTM Test Designation D-1557-91 (Modified Proctor). Structural fill under driveways, parking lots and sidewalks should be compacted to at least 90 percent maximum dry density, as determined by ASTM Test Designation D-1557-91 (Modified Proctor). Fill placed within I2~inches of finish grade should meet the 95% requirement. We recommend that Geo Group Northwest, Inc., be retained to evaluate the suitability of structural fill material and to monitor the compaction work during construction for quality assurance of the earthwork. 5.3 Spread Footing Foundations· The proposed buildings can be supported on conventional spread footings bearing on the dense native site soils or on compacted structural fill placed on top of the dense native site soils. Based on the findings from our soil investigation at the site, we anticipate that the dense soils are present between 2 feet and 3 feet below ground surface. Some over-excavation and placement of structural fill may be required at foundation locations, dependent upon the proposed finish grades. Individual spread footings may be used for supporting columns and strip footings for bearing walls. Our recommended minimum design criteria for foundations bearing on the dense site soils or on compacted structural fill are as follows: -Allowable bearing pressure, Dense native soil Compacted structural fill including all dead and live loads = 2,500 psf = 2,500 psf Geo Group Northwest, Inc. r March 17, 2005 Proposed 33-Lot Residential Development, King County, Washington G-1992 Page 8 -Minimum depth to bottom of perimeter footing below adjacent final exterior grade= 18 inches -Minimum depth to bottom ofinterior footings below top of floor slab = 18 inches -Minimum width of wall footings = 16 inches -Minimum lateral dimension of column footings = 24 inches· -Estimated post-construction settlement= 1/4 inch -Estimated post-construction differential settlement; across building width= 1/4 inch A one-third increase in the above allowable bearing pressures can be used when considering short-term transitory wind or seismic loads. · Lateral loads can also be resisted by friction between the foundation and the supporting compacted fill subgrade or by passive earth pressure acting on the buried portions of the foundations. For the latter, the foundations must l,e poured "neat" against the existing undisturbed soil or be backfilled with a compacted fill meeting the requirements for structural fill. Our recommended parameters are as follows: -Passive Pressure (Lateral Resistance) • 350 pcf equivalent fluid weight for compacted structural fill • 350 pcf equivalent fluid weight for native dense soil. -Coefficient of Friction (Friction Factor) • 0.35 for compacted structural fill • 0.35 for native dense soil We recommend that footing drains be placed around all perimeter footings. More specific details of perimeter foundation drains are provided below in Section 5.6 -Footing Drains. Geo Group Northwest, Inc. March 17, 2005 Proposed 33-Lot Residential Development, King County, Washington 5.4 Permanent Basement and Conventional Retaining Walls G-1992 Page 9 At the time of report preparation finish grades for the proposed residences were undetermined. We understand that a below-grade detention vault will be located at the northwestern comer of the site. We understand that the vault may have conventional retaining walls on the order of 10 to 12 feet in height.. The following design recommendations may be used for permanent basement and conventional retaining walls at the project site. Permanent basement walls restrained horizontally on top are considered unyielding and should be designed for a lateral soil pressure under the at-rest condition; while conventional reinforced concrete walls free to rotate on top should be designed for an active lateral soil pressure. Active Earth Pressure Conventional reinforced concrete walls that are designed to yield an amount equal to 0.002 times the wall height, should be designed to resist the lateral earth pressure imposed by an equivalent fluid with a unit weight of: • 35 pcffor level backfill behind yielding retaining walls • 45 pcf for a 25 percent sloped backfill • 60 pcf for a 50 percent sloped backfill At-Rest Earth Pressure Walls supported horizontally by floor slabs are considered unyielding and should be designed for lateral soil pressure under the at-rest condition. The lateral soil pressure design should have an equivalent fluid pressure of: • 60 pcf for level ground behind permanent unyielding retaining walls • 75 pcf for a 25 percent sloped backfill • I 00 pcf for a 50 percent sloped backfill Geo Group Northwest, Inc. March 17, 2005 Proposed 33-Lot Residential Development, King County, Washington Passive Earth Pressure and Base Friction G-1992 Page 10 The available passive earth pressure that can be mobilized to resist lateral forces may be assumed to be equal to 3 50 pcf equivalent fluid weight in both undisturbed soils and engineered structural backfill. · The base friction that can be generated between concrete and undisturbed native soils or engineered structural backfill may be based on an assumed 0.35 friction coefficient. We recommend that a vertical drain mat, Miradrain 6000 or equivalent, be used to facilitate drainage behind permanent concrete basement and conventional retaining walls. We recommend that the drainage mat be installed on the back side of the wall extending from the finish grade down to a footing drain pipe. The wall footing drain pipe should consist of a 4-inch diameter perforated rigid PVC pipe surrounded by a bed of washed gravel and separated from site soils by filter fabric, Mirafi 140N or equivalent. The drain pipe should be tightlined to discharge. Backfill behind conventional retaining walls should consist of free-draining sand or gravel soils which are compacted in lifts. Backfill in areas adjacent to basement or conventional retaining walls should be compacted with hand held t:quipment or a hoepack. Heavy compacting rnachim:s should not be allowed within a horizontal distance to the wall equivalent to one half the wall height, unless the walls are designed with the added surcharge. 5.5 Slab-on-Grade Floors Loose site soils should be excavated from all slab subgrade areas or compacted to a firm and unyielding condition. Slab-on-grade floors may be constructed on top of medium dense to dense native site soils or on top of compacted structural fill placed on top of the competent site soils. The slab-on-grade floors should not be constructed on top of the loose fills at the site. To avoid moisture build-up on the subgrade, slab-on-grade floors should be placed on a capillary break, which is in tum placed on the prepared subgrade. The capillary break should consist of a minimum of a six ( 6) inch thick layer of free-draining crushed rock or gravel containing no more than five (5) percent finer than the No. 4 sieve. A vapor barrier, such as a 6-mil plastic membrane, is recommended to be placed over the capillary break beneath the slab to reduce Geo Group Northwest, Inc. March 17, 2005 Proposed 33-Lot Residential Development, King County, Washington G-1992 Page 11 water vapor transmission through the slab. Two to four inches of sand may be placed over the barrier membrane for protection during construction. 5.6 Footing Drains We recommend that drains be install~d around the perimeter of the foundation footings. The drains should consist of a four ( 4) inch minimum diameter perforated rigid drain pipe laid at or near the bottom of the footing with a gradient sufficient to generate flow, as schematically illustrated in Plate 3 -Typical Footing Drain Detail. The drain line should be bedded on, surrounded by, and covered with a free-draining rock, pea gravel, or other free-draining granular material. The drain rock and drain line should be completely surrounded by a geotextile filter fabric, Mirafi 140N or equivalent. Once the drains are installed, the excavation should be backfilled with a compacted fill material. The footing drains should be tightlined to discharge into the storm water collection system. Under no circumstances should roof downspout drain lines be connected to the footing drainage system. All roof downspouts must be separately tightlined to discharge into the storm water collection system. We recommend that sufficient cleanouts be installed at strategic locations to allow for periodic maintenance of the footing drains and downspout tightline systems. 5.7 Pavements Based upon the site plan we understand that a new access roadway and cul-de-sac turnaround will be constructed running east-west near the center of the site. The adequacy of pavements is strictly related to the condition of the underlying subgrade. We recommend that all pavement subgrades be compacted by several passes of a large vibratory drum roller prior to placement of the crushed rock base. Before paving, we recommend that the subgrade be proof-rolled under the supervision of the geotechnical engineer to verify that the sub grade is firm and unyielding at the time of paving. The proof-roll may be performed by driving a fully loaded dump truck over the subgrade areas. If loose or yielding soils are encountered it may be necessary to over- excavate and replace with compacted structural fill in some areas. For firm and unyielding native subgrade soils we recommend the following minimum pavement sections for driveways: Class "B" Asphalt Concrete (AC) Crushed Rock Base (3/4-inch minus) 3 inches 6 inches Geo Group Northwest, Inc. March 17, 2005 Proposed 33-Lot Residential Development, King County, Washington Or Concrete Pavement Crushed Rock Base (3/4-inch minus) 6 inches 4 inches G-1992 Page 12 In accordance with the Washington State Department of Transportation Construction Manual, transverse cracks will develop in concrete slabs at about 15 foot intervals along the length of slabs and a slab wider than 15 feet may crack longitudinally. To control cracking of the concrete, contraction joints should be installed. Contraction joints are weakened planes which collect the cracking into a controlled joint, creating a maintainable joint in the slab, and preventing random ragged cracks which spread and require expensive maintenance. We recommend that contraction and construction joints be connected with #5 dowel bars, 30 inches long, 18 inches on center. The contraction joints should be placed at maximum 14 foot intervals. 6.0 LIMITATIONS This report has been prepared for the specific application to this site for the exclusive use of Mr. Cliff Williams of Belmont Homes, Inc. and his authorized representatives. We recommend that this report be iududc<l in ils eutinJty in the project contract documents for use by the cunlracior. Our findings and recommendations stated herein are based on field observations, our experience and judgement. The recommendations are our professional opinion derived in a manner consistent with the level of care and skill ordinarily exercised by other members of the profession currently practicing under similar conditions in this area and within the budget constraint. No warranty is expressed or implied. In the event the soil conditions are found to vary during site excavation, Geo Group Northwest, Inc. should be notified and the above recommendation should be re-evaluated. 7.0 ADDITIONAL SERVICES We recommend that Geo Group Northwest Inc: be retained to perform a general review oftbe final design and specifications of the proposed development to verify that the earthwork and foundation recommendations have been properly interpreted and implemented in the design and in the construction documents. We also recommend that Geo Group Northwest Inc. be retained Geo Group Northwest, Inc. March 17, 2005 Proposed 33-Lot Residential Development, King County, Washington G-1992 Page 13 to provide monitoring and testing services for geotechnically-related work during construction. This is to observe compliance with the design concepts, specifications or recommendations and to allow design changes in the event subsurface conditions differ from those anticipated prior to the start of construction. We anticipate the following construction monitoring inspections may be necessary: I. Site clearing and grubbing; 2. Over-excavation and structural fill placement at building foundation locations; 3. Verification of bearing soil conditions for foundations; 4. Structural fill placement and compaction; 5. Slab-on-grade preparation; 6. Subsurface drainage installation; 7. Proof-rolling of pavement subgrade areas. We appreciate this opportunity to have been of service to you on this project. We look forward to working with you as this project progresses. Should you have any questions regarding this report or need additional consultation, please feel free to call us. Sincerely, Geo Group Northwest, Inc. Adam Gaston Staff Engineer ~:::::.~ Principal Geo Group Northwest, Inc. . I ·1 I VICINITY MAP PROPOSED 33-LOT RESIDENTIAL DEVELOPMENT SW CORNER AT SE 192ND ST. & 102ND A VE. SE . KING COUNTY, WASHINGTON SCALE: NONE DATE: 3/l 1/05 MADE: AG CHKD: WC JOB NO: G-1992 PLATE BACKFILL WITH COMPACTED NATIVE SOIL GEOTEXTILE FILTER FABRIC, MIRAFJ 140N OR EQUIVALENT t 6 II to 12" •:• •'<' •.• .. ' .. :~ '. . . ,• <::·~~~-''. .... ·,,:,, /· FOOTING Jfi: FREE DRAINING BACKFILL CONSISTING OF WASHED ROUND ROCK OR CRUSHED ROCK . -::)-1~·/Y·: ><;:~~~..........,~ MINIMUM 4 INCH DIAMETER PERFORATED PVC PIPE LEVEL OR WITH POSITIVE GRADIENT TO DISCHARGE NOTES: NOT TO SCALE I.} Do not replace rigid PVC pipe with flexible corrugated plastic pipe. 2.) Perforated or slotted PVC pipe should be tight jointed and laid with perforations or slots down, with positive gradient to discharge. 3.) Do not connect roof downspout drains into the footing drain lines. Ill • Group Northwest, Inc. Geotechnlcal Engineers, Geologists, & Environmental Scientists TYPICAL FOOTING DRAIN DETAIL PROPOSED 33-LOT RESIDENTIAL DEVELOPMENT SW CORNER AT SE 192ND ST. & 102ND A VE. SE KING COUNTY, WASHINGTON SCALE NONE DATE 3/11/05 MADE AG CHKD · WC JOB NO. G-1992 PLATE 3 LEGEND OF SOIL CLASSIFICATION AND PENTRATION TEST UNIFIED SOIL CLASSIFICATION SYSTEM (USCSI MAJOR DIVISION GROUP TYPICAL DESCRIPTION LABORATORY CLASSIFICATION CRITERIA SYMBOL CLEAN GW WELL GRADED GRAVELS, GRAVEL-SAND Cu = (060 / 010) greater than 4 GRAVELS MIXTURE, UTILE OR NO FINES DETERMINE Cc" (D302) / (010 • D60) between 1 and 3 PERCENTAGES OF GRAVELS (!Jttle orno GP POORLY GRADED GRAVELS, AND GRAVEL-SANO GRAVEL AND SAND NOT MEETING ABOVE REQUIREMENTS (More Than Half fines) MIXTURES LITTLE OR NO F!NES FROM GRAIN SIZE COARSE-Coarse Gra!ns OISTRIBUTJON GRAINED SOILS Larger Than No. 4 CURVE ATTERBERG LJMJTS BELOW S!eve) DIRTY GM SIL TY GRAVELS, GRAVEL-SAND-SILT MIXTURES "A" LINE. GRAVELS CONTENT or P .I. LESS THAN 4 OF FINES (with some CLAYEY GRAVEi.$, GRAVEL-SANO.CLAY EXCEEDS 12% ATTERBERG LIMITS ABOVE fines) GC MIXTURES COARSE GRAINED "A" LINE. SOJLSARE or P.I. MORE THAN 7 CLASSIFIED AS Cu = (060 / 01 OJ greater than 6 SANDS CLEAN SW WELL GRADED SANOS, GRAVELLY SANOS, FOLLOWS: LIITLE OR NO FINES Cc .. (0302 ) I (010 • 060) between 1 and 3 SANDS (More Than Half (llttleorno POORLY GRADED SANOS, GRAVELLY SANOS, < 5% Fine Grained: More Than Half Coarse Grains SP NOT MEETING ABOVE REQUIREMENTS fines) LlffiE OR NO FINES GW, GP, SW, SP by Weight Larger Smaller Than No. Than No. 200 4 Sieve) ATTERBERG LIMITS BELOW Sieve SM SILTY SANOS, SAND-Sil T MIXTURES > 12% Fino Grained: "A"LINE DIRTY SANDS GM, GC, SM, SC CONTENT OF with P.l. LESS THAN 4 FINES 5to 12% Fine EXCEEDS 12% ATTERBERG LIMITS ABOVE (with SOmll SC CLAYEY SANDS, SAND-CLAY MIXTURES Grained: use dual "A"LINE fines) symbols with P.I. MORE THAN 7 liquid Limit ML INORGANIC SILTS, ROCK FLOUR. SANDY SILTS SILTS <50% OF SLIGHT PLASTICITY 60 (Below A-Line on PLASTICITY CHART J'1 A+lne 1--. v Plasticity Chart, FINE-GRAINED Liquid umt INORGANIC Sil TS, MICACEOUS OR -50 FOR SOil PASSING SOILS Negligible Organic >50% MH OIATOMACEOUS, FINE SANDY OR SIL TY SOil c NO. 40SlEVE I I V ~ 40 CH or OH, INORGANIC CLAYS OF LOW PLASTICITY, Liquid limit CL GRAVELLY, SANDY, OR SILTY CLAYS, CLEAN 0 J / CLAYS <30% .; (Above A-Una on CLAYS ~ 30 Plactlcity Chart, I [/ Negligible Organlc) liquid Limit CH INORGANIC CLAYS OF HIGH PLASTICITY, FAT ~ >50% CLAYS ~ 20 I Clor~l More Than Half ,I by Weight Smaller Liquid Limit ORGANIC SIL TS AND ORGANIC SIL TY CLAYS OF 0. 10 MHoroH-~ Th:;::-: ~lo. 200 " ORGANIC SIL TS <50% OL LOW PLASTiCITY I I I Sieve &CLAYS ~ "' 'Mt (Below A-Line on 40 ' b 60 Plactlclty Chart) Liquid Limit OH ORGANIC CLAYS OF HIGH PLASTICITY 0 10 20 30 70 80 90 10 ll >50% 0 0 LIQUID LJMIT (%) HIGHLY ORGANIC S01LS Pl PEAT AND OTHER HIGHLY ORGANIC SOILS SOIL PARTICLE SIZE GENERAL GUIDANCE OF SOIL ENGINEERING PROPERTIES FROM STANDARD PENETRATION TEST (SPT) U.S. STANDARD SIEVE FRACTION Paaslng Retained SANDY SOILS SILTY & CLAYEY SOILS Sieve Size Sieve Size Unconfined Blow Relallve Friction Blow (mm) (mm) Counts Density Angle Descr1pllon Counts Strength Description SILT/CLA.Y #200 0.075 N % ¢,, degree N qu, tsf = 0-4 0 -15 Very Loose <2 <0.25 Vo,y sofl FINE #40 0.425 #200 0.075 4 -10 15-35 26-30 Loo,e 2-4 0.25 • 0.50 Sofi MEDIUM #10 2 #40 0.425 10 -30 35. 65 26-35 Medium Dense 4-8 0.50 • 1.00 Medium Stiff COARSE #4 4.75 #10 2 30· 50 65-65 35-42 Dense e • 15 1.00 • 2.00 Stiff ->50 65 • 100 38 ·48 Very Dense 15-30 2.00 • 4.00 Very Stiff FINE 19 #4 4.75 > 30 >4.00 "'"' COARSE 76 19 ........... COBBLES 76 mm to 203 mm • Group Northwest, Inc. >203mm BOULDERS Geotechnical Engineers, Geologists, & ROCK Environrrantal Scientists > 76 fTVll FRAGMENTS· 13240 NE 20th street. SUile 12 Bellevue, WA 98005 ROCK >0.76 cubic meter In volume Phone {425) 64s'.-S757 Fax (425) 649-8758 PLATE A1 I ~ TEST PIT NO. TP-1 LOGGED BY AG TEST PIT DATE: 3/9/05 DEPTH SAMPLE Water OTHER TESTS/ ft. uses SOIL DESCRIPTION No. % COMMENTS 4" thickness forest duff ] Probe 6-12" -Sl 20.7 Probe 12" -SM Orangish Brown Silty SAND with some gravel and cobbles, moist, loose -----------------------------------------------------------~ S2 19.9 SM Tan silty SAND with some gravel and cobbles, moist, dense - 5 SM some cementation S3 21.2 -Total depth of test pit= 5 feet bgs -No groundwater seepage - - 10 _ - - - - 15 _ . TEST PIT NO. TlP'-2 LOGGED BY AG TEST PIT DATE: 3/9/05 DEPTH SAMPLE Water OTHER TESTS/ ft. uses SOIL DESCRIPTION No. % COMMENTS 4" thickness forest duff Probe 24" -Orangish Brown silty SAND with some gravel and cobbles, charcoal SM ':J -nieces. moist. loose . Sl 15.6 ----------------------------------------------------------. Probe 3-4" -SM Mottled gravelly silty SAND with occasional cobbles, moist, dense -J S2 15.4 Probe 2-3" 5 -SM/ Gray fine silty SAND to sandy SILT with some gravel and occ. J ML cobbles, very dense S3 14.3 -Total depth of test pit = 6 feet -No groundwater seepage - 10 _ - - - - 15 _ TEST PIT LOGS ~ PROPOSED 33-LOT RESIDENTIAL DEVELOPMENT -Group Northwest, Inc. SW CORNERATSE192ND ST. & 102NDAVE. SE ......... GeotecJ'!nical Engineers, Geologists, & KING COUNTY, WASHINGTON Environmental Scientists · JOB NO. G-1992 I DATE 3/10/05 I PLATE A2 TEST PIT NO. TP-3 LOGGED BY AG TEST PIT DATE: 3/9/05 DEPTH SAMPLE Water OTHER TESTS/ ft. uses SOIL DESCRIPTION No. % COMMENTS SM 12-18" thickness loose forest duff Probe 12-18" ------------------------------------------------------------J SI 18.7 Probe 8-10" -SM Orangish Brown gravelly/cobbly silty SAND, moist, loose -------------------------------------------------------------0 S2 17.6 SM Mottled gravelly/cobbly silty SAND, moist to wet, dense - 5 -SM/ Gray silty SAND to sandy SILT with some gravel, moist to wet, very b ML S3 17 . Total depth oftest pit= 6 feet bgs . No groundwater seepage . 10 _ ·- . . . . 15 _ TEST PIT NO. TP-4 LOGGED BY AG TEST PIT DATE: 3/9/05 DEPTH SAMPLE Water OTHER TESTS/ ft. uses SOIL DESCRIPTION No. 'I, COMMENTS 6" thickness loose forest duff Probe 24" -Orangish Brown fine silly SAND with some gravel, cobbles and SM -boulders, moist, loose ----------------------------------] --------SI 12.1 -SM Tan silty SAND with some gravel, moist, dense Probe 1-3" - 5 some cementation and cobbles ] S2 13 - -Total depth of test .pit = 6 feet . No groundwater seepage - 10 _ . . . - 15 _ TEST PIT LOGS ~ PROPOSED 33-LOT RESIDENTIAL DEVELOPMENT -~ Group Northwest, Inc. SW CORNER AT SE 192ND ST. & 102NDAVE. SE --=-Geotechnical 8lglneers, Geologists, & KING COUNTY, WASHINGTON Envlronrrental Scientists · JOB NO . G-1992 [ DATE 3/10/05 I PLATE A3 . TEST PIT NO. TP-5 LOGGED BY AG TEST PIT DATE: 3/9/05 DEPTH SAMPLE Water OTHER TESTS/ ft. uses SOIL DESCRIPTION No. o/, COMMENTS SM 6-12" thickness loose forest duff Probe 6-18" ----· -----Orangish Brown silty SAND with some gravel and acc. co1iTifes, ----:i SI 16.8 -SM moist, loose ---· -------------------------------------------------------. -Tan to mottled fine silty SAND with some gravel, moist to wet, dense J. S2 12.3 SM Probe 1-3" - 5 - SM Brown gravelly/cobbly silty SAND, moist, very dense -Total depth oftest pit= 6 feet bgs -No groundwater seepage - 10 _ - - - - 15 _ I TEST PIT NO. TP-6 LOGGED BY AG TEST PIT DATE: 3/9/05 DEPTH SAMPLE Water OTHER TESTS/ ft. uses SOIL UESCRIPTION No. o/, COMMENTS 6-12" thickness loose forest duff Probe 24" ---------Orangish Brown fine silty SAND with some gravel and cobbles SM ] Probe 4-10" -moist, loose ___________________________ --------______ _ SI 11.9 ---------SM Tan silty SAND with some gravel and cobbles, moist, dense -some cementation b S2 15.3 5 - - -SM Mottled gravelly/cobbly silty SAND, moist, very dense ] S3 14.3 -SM Brown gravelly silty SAND with occ. cobbles and boulders, moist, -very dense 10 _ u: S4 11.3 -Total depth oftest pit= 11 feet -No groundwater seepage - 15 - TEST PIT LOGS .......... (CCD'@ Group Northwest, Inc. PROPOSED 33-LOT RESIDENTIAL DEVELOPMENT SW CORNER AT SE 192NDST. & 102NDAVE. SE -Geotechnlcal Engineers. Geologists. & KING COUNTY, WASHINGTON Envlronrrental Scientists · JOB NO. G-19921 DATE 3/10/05 I PLATE A4 TEST PIT NO. TP-7 . LOGGED BY AG TEST PIT DATE: 3/9/05 DEPTH SAMPLE Water OTHER TESTS/ ft. uses SOIL DESCRIPTION No. % COMMENTS SM 6" thickness loose forest duff ] Probe 12-18" -Orangish Brown silty SAND with some gravel and cobbles, moist, SI 14.8 Probe 4-10" SM I.ans•-------------------------------------------------------- SM Tan to mottled fine silty SAND with some gravel, moist, dense ] -S2 13.8 - 5 SM Gray gravelly silty SAND with some cobbles, moist, very dense -Total depth oftest pit= 5 feet ligs No groundwater seepage - - - 10 _ .. - - - - 15 _ TEST PIT NO. TP-8 LOGGED BY AG TEST PIT DATE: 3/9/05 DEPTH SAMPLE Water OTHER TESTS/ ft. uses -· ···---···-' SOIL DESCRIPTION No. % COMMENTS SM 6-8" thickness loose forest duff Probe 10-12" -Orangish Brown silty SAND with some gravel, moist, loose ----------------------.---------------------------------------] SI 17.3 -SM Tan silty SAND with some gravel and acc. cobbles, moist, dense Probe <l 11 -SM Gray gravelly fine silty SAND with some cobbles, moist, v. dense 5 S2 14.7 -Total depth of test pit= 5 feet -No groundwater seepage - - 10 _ - - - - 15 _ TEST PIT LOGS ........... • Group Northwest, Inc. PROPOSED 33-LOT RESIDENTIAL DEVELOPMENT SW CORNER AT SE"I92ND ST. & !02NDAVE. SE GeotechnlcaJ Engineers, Geologists, & KING COUNTY, WASHINGTON Environrremal Scientists · JOB NO. G-1992 I DATE 3/10/05 I PLATE A5 TEST PIT NO. TP-9 LOGGED BY AG TEST PIT DATE: 3/9/05 DEPTH SAMPLE Water OTHER TESTS/ ft. uses SOIL DESCRIPTION No. 'I, COMMENTS SM 6 11 thickness loose forest duff Probe 6-12" -Probe 6-16" SM Orangish Brown silty SAND with some gravel, moist, loose - -1------------------------------------------------------------] Sl 12.3 SM Tan silty SAND with some gravel, moist, dense - 5 · SM Gray gravelly silty SAND with some cobbles, moist, very dense ,., S2 13.2 -Total depth oftest pit= 5 feet bgs No groundwater seepage - - - 10 -.. - . . . 15 _ I TEST PIT NO. TP-10 LOGGED BY AG TEST PIT DATE: 3/9/05 DEPTH SAMPLE Water OTHER TESTS/ ft. uses SOiL DESCRIPTION No.· % COMMENTS 4" thickness loose forest duff Probe 2-8" -Probe 8-16" -SM Orangish Brown silty SAND with some gravel and cobbles, moist, J SI 17.4 loose -------------------------------------------------------------SM Tan silty SAND with some gravel, moist to wet, dense ] S2 17.6 - 5 SM/ Gray silty SAND to sandy SILT with some gravel and occ. cobbles -and boulders, moist, v. dense ML S3 14.1 -Total depth oftest pit= 6 feet -No groundwater seepage - 10 _ - - - - 15 _ TEST PIT LOGS· .......... g PROPOSED 33-LOT RESIDENTIAL DEVELOPMENT Group Northwest, Inc. , SW CORNER AT SE 192ND ST. & 102ND A VE. SE Geotechnlcal Engineers, Geologists, & KING COUNTY, WASHINGTON Envlronrrental Scientists · JOB NO. G-1992 I DATE 3/10/05 I PLATE A6 •. ··• · .. 4 t · .... \MUL.T \ i ·. \ \ \ ! : ,J ( ! ' 358_·:. ._!.. •• ... _.-...:= ~p~ ~.-<~~-~- \ I ~ 1 ( . -. . -, i ~ .... r l-, ·1 : / 384 384 r1 (JO 31*> '.l \r . _,'J . / .. ) ,: ir . ·e• ; ~ . I . -·1 •. 8'1 ., ':\' \ '·ti ' ,. ___ _ · 3S2 ·di ·,• ; \ I' i ! . ,, .. . , 1 ·. . ... ' ·1 ' ( .. .,... _i::b_ . . 384 • • 384 t. l \ : 1': '.. '... -i:::t-' ', ~84 \ i I . . ·--.TP~7 l . 11 ~·--·-- • \ '. ' ... ) 11 . . i 3110 ·. ! ?~ j,'?84 ·\ ·,· 3'!12 3S2 rr ;.9,4 ~94 3S4 i t)f,, -~·· \_ 1-:es_.< 3'.l'i-••·~------4 -$TP-9 • (.-->~· ··-.. ~~ 3~· 3eo ! / I 3SO ·, ., ;.:. SE\)92\ND ,ls T 400 ::;~ l•" -·.·;,t; 3o/.::,, 3'96_ .. .9t, ''\ - 400 "lj !/ ~C.,· \ ·.;412 \ ii i ! ' '' ?~ ........ gt;, ·:... '\ \ I i)) i--~__:.~ . •, ' ',. __ _ ..... -·~·'. ( / f /; . . \~f,-,~·-:---'---'-__I j ~ \.~. 1382 ;;s 38& ·t • • ! ,-$ ,·· ~4 t ~5 I= ,. _:::~ • 3?> 3~S ,~ \ . . • • 46c, 4~2 ~410 ! ' ' ', ' :, v; ~j '2 11c1,\ i, i •. ' .' 334 .' ~ i L 1 :. ', \ \ ) . !. :l. te, ·1 (1 . ; ; i ---.f· -( • "/ .-; "1 • (~~$TP-~ • r A ; \ \ ,·, !) ! ( \_ 'l""\ ' . ' . . -,I '\ ·. 314 i, __ _ ~~ . "", TP-10 :!,f \ . . ' TP-8. ·-. ; :"~O ..,!02 :' -.. I . . l . ' +\ I I / ' ' ' ,J .•• . ::J4 ,,_ \ ••. 1 . .,,..-~·· ··./ . ; ,9t ·····-----~-:,,--.....J~------.::.... -3S& - ; ' \ . ;i,e, i 380'. _; 388 3'34 . :_ ·, . \··::-.... A)e, 404 400 .··-- 39b I . I . i. ' · ' ' ·, · & · .. '. 1 '. ';;1& -·-·-. t -L: , . . . y ·~J >.. -. 1·· ···1 .. i 318. . ···l~%' . ' .. . I ~ ' . /I •• --r-:-_..:...:_, _ _:::_ i, ----r--=-..1...:. I' . ... .. ' i4. 402 .J 4C)4 '·\ 402 lf 31-< 38& ?88 3"30 ' \_ \ J ~~o ·364. !3,&2 ·-, i 3-14 t, <: \ ....J-...... ·-3&8 ; 66; { . ..,,;3,C, eo .··---.... \ ·,\ ·.3S2·\.~ .· 1<._ t 3S4 ,4 -$~P-1 . I ~,~ -3~C 3 : *TP-2 -312 \ ~ ·. '16 • *TP-3 -• 3~0 . -\'2-: 0 ... "' .. J . 33& ·' 338 ~--~-: . TP' 7.: .-.,-·~ r•· d , .• i ·, ~ \,\ . ' ' \.,...t ., . .. ····,8 (,, . . s 3 ~~--- 2. i ! . 3<;1 ·.: I \ •, ~,. / 4i2 ,, • 412 .,, 412 "' \ : r 40 ,. ! I l l ; , ;~~--. j ! ~8 \_ - i ll1 .\, : I, (.fj . i uJ > . ! <:[ ! Q z C'l a 402 \.,~ ... 3-46~ \_ . .:>Sb ~ ;;s4-l • 364 -, 3-1:~ 02 ·-330 :3-34 },32 '. ·. 342 :340· • .i -~ ·, ' \ l l j ' LEGEND ~P-1 TEST PIT "IUMBER AND APPROXL'\tA TE LOCATION : ', ' '0 . I 46·[}..· -l ' T Site Plan based upon preliminary plans provided by Belmont Homes, Inc. -SITE PLAN (@@ Group Northwest, Inc. PROPOSED 33-LOT RESIDENTIAL DEVELOPMENT SW CORNER AT SE 192ND ST. & 102ND A VE SE I Geotechn<al Eng;,ee,5. Geologi,ts, & I ' KING COUNTY WASHINGTON -----· -··· Environmental Scientists , I I I SCALE 1"=40' DATE 3/11/05 MADE AG CHIO>. WC JOB NO. G-1992 PLATE 30' 2 I Transportation Planning & Engineering Cliff Williams, P.E. Belmont Homes, Inc. P.O. Box 2401 Kirkland, WA 98083-2401 Re: Talbot Ridge Estates Preliminary Plat King County LUSD File No. L05P0007 Traffic Impact Analysis Addendum Dear Mr. Williams: August 11, 2005 RECEIVED AUG 2 ~ 2005 KING COUNTY LAND USE SERVICES ci z ci -0 a, -z .:::: ,9 E a, = '-' X a, a, w == a: At your request, we have prepared this Traffic Impact Analysis Addendum to provide the information requested in the Traffic/Roads items in the Plat Screening Transmittal from King County dated June 28, 2005. The County's information request was in response to our Traffic Impact Analysis (TIA) report for this project dated March 21, 2005. A copy of the County's Transmittal is attached. Existing Roadway Classification According to the functional street classification lists and maps on their web sites, neither the City of Renton nor the City of Kent currently classifies S. 192"d Street. However, the continuation of S.E. 192"d St. west of 99th Pl. S. is in Renton, and is named S. 55th Street. Renton does not classify S. 55th St. as an arterial street. We have also learned that a property just west of the Talbot Ridge Estates site, south of S. 55th Street, is in the process of being annexed into the City of Renton. Due to the proximity of the existing Renton City limits and this proposed annexation, it is apparent that the Talbot Ridge Estates site is more likely to some day become a part of Renton rather than Kent. As noted in the County's Plat Screening Transmittal, S.E. 192"d St. is an unclassified (i.e. not an arterial) roadway. Since S.E. 192"~ St. is not designated as an arterial in any of the current roadway classification systems for the agencies in the area, no additional right-of way dedication on S.E. 192"d St. is required in order to be consistent with current roadway classification standards. Existing Entering Sight Distance (ESD) An existing ESD deficiency on S.E. 192"d St. to the west of 102"d Ave. S.E. was identified and discussed extensively in the TIA (pages 2 -4 ). Due to the limitations of the available right-of-way and the existing topography, widening or relocation of S. 192"d St. to ~ a, c:: .E "' X w r::,, c:: ·c: . "' a, :c ' > -c:: :::, 0 Ll en c:: ""' mitigate the existing ESD deficiency does not appear to be practical. As requested in the ~ County's Plat Screening Transmittal, attached is a request for a Variance from the Road f Standards for the existing ESD deficiency. K0433205addondum.doc Mirai Associates, Inc. o 11410 NE 122nd Way, Suite 320 o Kirkland, WA 98034-6927 o 425.820.0100ru["4,BW~lf!5C'OPV ~IM~U'@~III I Trans.portation Planning & Engineering Cliff Williams, P.E. Belmont Homes, Inc. August 11 , 2005 Page 2 Eastbound Right Turn Lane As requested in the County's Plat Screening Transmittal, an evaluation was conducted to determine whether the criteria would be met for an eastbound right tum lane on S.E. 192"d St. at the 102"d Ave. S.E. intersection. The criteria used was Figure 910-12 Right-Tum Lane Guidelines of the WSDOT Design Manual. In general, for lower traffic volume conditions, the figure recommends only a right tum radius on the comer of an intersection. For intermediate volume conditions, the figure recommends that a right tum pocket or taper should be considered, and for higher volume conditions the figure recommends that a right tum lane should be considered. A copy ofWSDOT Figure 910-12 is attached. Also attached is a table showing the Eastbound Right Tum Lane Analysis results for the S.E. 192"d St./102"d Ave. S.E. intersection, based on the relevant traffic volumes and WSDOT Figure 910-12. As shown on the first line of the table, for the existing 2005 PM peak hour volume of five vehicles making the eastbound right tum, a radius only is recommended. For the projected 2007 PM peak hour volumes without the Talbot Ridge Estates project (5 right turns), a radius only is recommended. For the projected 2007 PM peak hour volumes with the Talbot Ridge Estates project (19 right turns), a radius only is still recommended. The County's Plat Screening Transmittal mentioned a proposed 18-lot subdivision (A05PM079) of the property near the southerly terminus of 102" Ave. Southeast. Using ITE trip generation rates for Single Family Detached Housing (as discussed on pages 4 and 5 of the TIA), this subdivision would generate 18 vehicle trips during the PM peak hour. Using the same trip distribution as was used for the Talbot Ridge Estates (as shown on Figure 4 of the TIA), eight of these trips would be making the eastbound right tum from S.E. 192"d St. onto 102"d Ave. Southeast. As shown on the attached table showing the Eastbound Right Tum lane Analysis results, for the projected 2007 PM peak hour volumes with both this proposed 18-lot subdivision (A05PM079) and Talbot Ridge Estates, WSDOT Figure 910-12 recommends that a right-tum pocket or taper should be considered. As shown on the attached Figure 910-12, the plotted point for the relevant traffic volume projections (487, 27) is near the lower edge of the "Consider right-tum pocket or taper" area of the graph, just above the "Radius only" line. Therefore, the recommendation from Figure 910-12 is marginal in nature. All of the plotted points on the attached Figure 910-12 are well below the "Consider right-tum lane" area of the graph. An eastbound right tum lane is not warranted on S.E. 192"d St. at the 102"d Ave. S.E. intersection. Southeast 192"d St. climbs the hill from Talbot Rd. S. up to 102"d Ave. Southeast. The road was constructed with a series of horizontal curves and "hairpin" turns winding up the hill. K0433205addendum.doc ~IIMl ~ w@ ~Ill I Trans_por.tation Planning & Engineering Cliff Williams, P.E. Belmont Homes, Inc. August 11, 2005 Page 3 The grade crests at the west edge of the 102"d Ave. S.E. intersection, then the road is relatively level through the intersection and continuing to the east. About midway between the intersection and the first horizontal curve located to the west, the grade on S.E. 192"d St. approaching the intersection eastbound was measured to be approximately 9%. Southeast 192"d St. west of the 102"d Ave. S.E. intersection is well posted with tum and winding road warning signs with 15 MPH advisory speeds for both directions of travel. The eastbound approach to the 102"d Ave. S.E. intersection is also posted with a cross road warning sign with a 20 MPH advisory speed. The existing roadway grade, horizontal turns, and traffic control devices reduce the speeds of eastbound traffic on S.E. 192"d St. approaching the 102"d Ave. S.E. intersection. Also, since S.E. 192"d St. is not an arterial and the surrounding area is residential, higher speeds are not desirable. A right tum pocket or taper would tend to encourage higher speeds for eastbound through traffic and for eastbound right turn traffic. A right tum pocket or taper would also increase roadway crossing distances for pedestrians. Combined with somewhat higher vehicle speeds, this would make those intersection crossings somewhat less safe for pedestrians. The accident report data provided by King County staff for the four-year period from January 1, 2000 to December 31, 2003 showed only one accident at the S.E. 192"d St./102"d Ave S.E. intersection. The accident was a right angle accident that occurred at 8:20 PM at night on 11 /13/03 and resulted in property damage only. The accident data does not indicate a need for a right turn pocket or taper. As noted above, an eastbound right turn lane is not warranted on S.E. 192"d St. at the 102"d Ave. S.E. intersection. Also, for the reasons discussed above, we believe that a right- turn pocket or taper should not be required on S.E. 192"d St. approaching the intersection eastbound. If you have any questions, please contact me at (425) 820-0100 or via e-mail at dave@miraiassociates.com. DHE: Very truly yours, Mirai Transportation Planning & Engineering ):r~}.~ David H. Enger, P.E., P.T.O.E. Senior Associate K0433205addendum.doc ®' · . . Kina Cowttr llepamiont of Devolopmenr andBnvtroommr.lSorv!ces Len:! Uoe Scmcea Division 9000-Avenue 5- Relllnn, Wuhlogton ~0.SS.lll9 .· '. !.' f~~i~\;~;1Wi{~11ttit\C(l)i~~tit;·n~;;Bf!~i~i~it~Iti?:1~\(;~}/~·;'·~:::,J;i;~;:'.i,~:·::r::.·.:.·;: \ ~: .. : .. \ ·.1 '.'. . Please submit ten ( 10) copies of the following unless otherwise noted: IRecreatioi Space: Per KCC 21A.14.180, the proposed plat is required to provide 390 square feet of recreation space per lot Provide a conceptual recreation plan indicating the type of improvements (i.e. sport court, play structure, benches, landscaping, etc.) proposed. For developments of26 to 50 dwelling units, at least two or more of the recreation facilities listed shall be provided in addition to the tot lot or children's play area: a. playground equipment; · . b. sport court; c. sport field; d. tennis court; or e. any other recreation facility proposed by the applicant iind approved by the dh:ector: Please note the following recreation space design requirements. Recreation space shall: o Be of a grade and surface suitable for recreation improvements and have a maximum grade of five percent; o Be located in an area where the topography, soils, hydrology and other phyiiical characteristics are of such quality as lo create a flat, dry, obstacle-free space in a configuration which allows for ·passive and active recreation; o Be cen1rally located with good visibility of the site :from roads and sidewalks; o Have no dimensions less than thirty feet; o Have a street roadway or parking area frontage along ten percent or more of the recreation space perimeter if the required outdoor recreation space excee4s five thousand square feet. Drainage; A drainage adjusunent is required to concentrate and route the post-developed drainage to the northwest comer of the site. The existing drainage appears to sheet flow westerly to 9.9th Place S, then south toward Eden Creek Please provide a Level 1 Offsite Analysis for the existing drainage course. Please revise the Level 1 Analysis and conceptual plan to include an evaluation of how the individual Lot BMP requirements will be met in the 2005 Drainage Manual. · Please correct several references in the Level I Downstream Analysis from "east" to west Provide cross-section views of the west portion of the site, showing the proposed detention vanlt area and the proposed stormwater connection to the SE 192nd Street drainage system. Evaluate the close proximity of the proposed connection to existing property lines and required easements/setbacks. Traffic/Roads: SE 192"d Street is an unclassified (i.e. not an arterial) roadway, that appelll!I to have traffic volwnes considerably above the maximum volumes typically associated with a Neighborhood Collector -and unlikely to change since there are no proposed capacity improvements to paralleling roadways: South 212111 , South 200th, Carr Road, that provide connections between Benson Highway and the Green River Valley. This roadway has had an arterial designation by the City of Kent, and may also have an arterial designation by the City of Renton. Please research the clllTC!lt status of the classification by these two agencies, and the most recent .Ber LF/PlatSCR.Sul> 2/24/ge olo . . available information about which agency will be annexing the area, and identify any additional right-of-way · that would be required to be dedicated to be consi.stent with that agency's designation for the roadway. • . ·· 102nd Avenue SE, south of St! 192nd. Street, appears to have limited potential to be !!Xtended to connect with any other existing public roadways, however there is significant potential for additional subdivision development along this section of the road. It may, thercfore,.result in traffic volumes near the threshold for a neighborhood collector. Therefore, please revise the site plan to show frontage improvements consistent with a neighborhood collector roadway width (18 feet from centerline to curb line) across the entire frontage. The TIA indicates that ESD requirements of the 1993 KCRS, looking west, are not met. Some mitigation is identified, but is noted as being impractical or of limited benefit. Please evaluate whether any physical changes (widening or limited realignment) to SE 19200 Street would mitigate the ESD deficiency. [n addition, the Applicant must apply for-and receive approval for-a Variance to the Road Stsnclards for the BSD deficiency. Please provide an addendum to the TIA to address that also includes ~e additional trip activi] associated with a · proposed 18-lot subdhision (A05PM079) of the property near the southerly terminus of 1-02 A venue SE. . Specifically, please provide an evaluation of whether the criteria for an eastbound right tum lane would be met under llith the proposed plat either (a) by itself, or (b) with the cumulative development of this proposed subdivision with other developable property served by 1021111 Avenue SE. . . Revised Preliminary Plat: Provide 2S copies of a revised pre!iminaty plat, as necessary, as a result of the referenced requests for additional information. Include 2 copies on legal-ske paper. As a result of the review of the information, additional information (studies, revisions, etc.) may be requested at a iater date. Further evaluation of these issues may result in the reconfiguration/reduction in lots . • scr --~ ...... _ -·~ -. -·-. ·-- Condition Existing 2005 PM Peak Hour, Eastbound Right Turn Lane Analysis On S.E. 192nd St. at 102nd Ave. S.E. Talbot Ridge Estates Traffic Impact Analysis Addendum Eastbound Eastbound Eastbound Right Turn Through Right+ Thru Volume Volume Volume 5 452 457 Counted 4:45 -5:45 Thursday, 3/3/05, as shown on TIA Fig. 5 2007 PM Peak Hour Without Project, as shown on TIA Fig. 6 5 460 465 2007 PM Peak Hour With Project, as shown on TIA Fig. 7 19 460 479 2007 PM Peak Hour With Project, 27 460 487 Plus 18-lot plat at south end of 102nd Ave. S.E. K0433205RTibl.xls 8110/2005 Right-Tum Lane Guideline WSDOT Design Manual Figure 910-12 Radius only Radius only Radius only Consider right-turn pocket or taper Mirai Transportation Planning and Engineering 100 G) E :::, 0 > 60 E :z .s::. f 40 ... :::, 0 ::i:: ~ ro ~ 20 0.. 0 ) Consider right-tum t-----t----t---~k:-----t-lane<5l +-----1 0 Consider right-tum pocket or taper•) 100 200 300 400 500 600 Peak Hour Approach Volume (DDHV) <1> 700 I (1) For two-lane highways, use the peak hour QQl:lll (through+ right-turn). I For multilane, high speed highways (posted speed 45 mph or above), use the right-lane peak hour approach volume (through + right-turn). For multilane, low speed highways (posted speed less than 45 mph), there is no traffic volume right-turn lane or taper requjrement. (2) When all three of the following conditions are met, reduce the right-turn DDHV by 20. • The posted speed is 45 mph or less • The right-turn volume is greater than 40 VPH. • The peak hour approach volume IDDHY) is less than 300 VPH. (3) See Figure 910-B. for right-turn corner design. (4) See Figure 910-13. for right-turn pocket or taper design. (5) See Figure 910-1~ for right-turn lane design. (6) For additional guidance, see 910.07(2) in the text. lnt11rs11ct1ons At Grade Psge910-28 Right-Turn Lane Guldellnes<6> Figure 910-12 Engl/sh Version Design IV/snusl IV/sy 2001 I Transportation Planning & Engineering August 11 , 2005 Cliff Williams, P.E. Belmont Homes, Inc. P.O. Box 2401 Kirkland, WA 98083-2401 Re: Talbot Ridge Estates Preliminary Plat King County LUSD File No. L05P0007 Entering Sight Distance Variance Request Dear Mr. Williams: We have prepared this request for a Variance from the Road Standards for the existing Entering Sight Distance (ESD) deficiency on S.E. 192"d St. to the west of 102nd Ave. Southeast. This request was prepared in response to the Traffic/Roads items in the Plat Screening Transmittal from King County dated June 28, 2005. The County's information request was in response to our Traffic Impact Analysis (TIA) report for this project dated March 21, 2005. An existing ESD deficiency on S.E. 192nd St. to the west of 102nd Ave. S.E. was identified and discussed extensively in the TIA (pages 2 -4). We conducted a sight distance review on S.E. 192nd St. for the northbound approach on 102nd Ave. Southeast. The results of the available stopping sight distance (SSD) and entering sight distance (ESD) measurements at this intersection are shown in the following table: Type of Sight Distance To/from the To/from the King County East West Design Criteria Stopping Sight Distance Over 500 Approx. 320 * 250 (ft.) Entering Sight Distance Over800 Approx. 340 490 (ft.) * SSD to 24" high object per current AASHTO standards. Due to crest of grade on the west edge of the intersection, the SSD to a 6" high object is approximately 140 feet. This table also shows the King County Design Criteria for SSD and ESD per Table 2.1 in the King County Road Standards -1993 (KCRS). The KCRS K0433205ESDvsr/ance.cJoc Mira! Associates, Inc. o 11410 NE 122nd Way, Suite 320 o Kirkland, WA 98034-6927 o 425.820.0100. to 425.821.1750 -f ~I !Ml fl rr @ fl Iii I Transportation P18nning & Engineering Cliff Williams, P.E. Belmont Homes, Inc. August 11, 2005 Page2 recommended sight distances are for a design speed of 35 MPH. Per County policy, the design speed is the posted speed limit (25 MPH on S.E. 192"d St.) plus 10 MPH (total of 35 MPH design speed}. Our field review shows that the County's SSD criterion of 250 feet is met both to the east and west along S.E. 192"d St. at the 102nd Ave. S.E. intersection. For the northbound approach to the intersection, the County's ESD criterion of 490 feet is also met to the east. However, to the west of the 102nd Ave. S.E. intersection, the existing available ESD along S.E. 192"d St. was measured to be approximately 340 feet. The sight distance is limited by vertical obstructions on the north side of S.E. 192"d St. on the inside of a horizontal curve in the roadway. The initial obstruction is a line of five Douglas fir tree trunks, ranging in diameter from about 8" to 20". The lower branches have been removed, so increasing the sight distance would require removal of the trees themselves. The trees are located back from the roadway, near the right-of-way line, and appear to be within the County right-of-way. It is estimated that removing these five trees would increase the ESD to approximately 370 feet. Since this is a gain of only about 30 feet of ESD, removal of the trees does not appear to be worthwhile. If the trees were removed, the sight obstructions would then become the private fences located on or near the County road right-of-way line. Additional structures and vegetation located on private single family residential properties north of the fences would also need to be removed in order to further increase the ESD. Removal of these structures and vegetation would require the purchase of additional property or easements from the homeowners on the north side of the road. This would be expensive, time consuming, likely involving legal complications, and ultimately impractical. The existing ESD deficiency on S.E. 192"d St. west of the 102nd Ave. S.E. intersection is mitigated by the existing roadway geometry and the existing traffic control devices installed and maintained by the County. Southeast 192"d St. climbs the hill from Talbot Rd. S. up to 102nd Ave. Southeast. The road was constructed with a series of horizontal curves and "hairpin" turns winding up the hill. The grade crests at the west edge of the 102nd Ave. S.E. intersection, then the road is relatively level through the intersection and continuing to the east. About midway between the intersection and the first horizontal curve located to the west, the grade on S.E. 192"d St. approaching the intersection eastbound was measured to be approximately 9%. K0433205ESDvariance.doc ~!MflIT'@fl!~ I Treneportntion Plenning & Engineering Cliff Williams, P.E. Belmont Homes, Inc. August 11, 2005 Page 3 As noted in the County's Plat Screening Transmittal, S.E. 192nd St. is an unclassified (i.e. not an arterial) roadway. The posted speed limit is 25 MPH. West of the 102°d Ave. S.E. intersection, S.E. 192nd St. is well posted with tum and winding road warning signs with 15 MPH advisory speeds for both directions of travel. The eastbound approach to the 102°d Ave. S.E. intersection is also posted with a cross road warning sign with a 20 MPH advisory speed. The existing roadway grade, horizontal turns, and traffic control devices reduce the speeds of eastbound traffic on S.E. 192"d St. approaching the 102nd Ave. S.E. intersection. The accident report data provided by King County staff for the four-year period from January 1, 2000 to December 31, 2003 showed only one accident at the S.E. 192nd St./102nd Ave S.E. intersection. The accident was a right angle accident that occurred at 8:20 PM at night on 11/13/03 and resulted in property damage only. The direction of travel of the vehicles involved is not apparent from the data provided. However, since the accident occurred at night, and vehicle headlights would have been on, ESD does not appear to be a factor in this accident. Further improvements to increase the ESD west of the intersection do not appear to be worthwhile or practical. Due to the limitations of the available right-of-way and the existing topography, widening or relocation of S. 192"d St. to mitigate the existing ESD deficiency does not appear to be feasible. The current SSD criteria are met. ESD does not appear to be a factor in any traffic accidents at the intersection. For these reasons, we believe that the County should grant a Variance from the Road Standards for the existing Entering Sight Distance (ESD) deficiency on S.E. 192"d St. to the west of 102nd Ave. Southeast. If you have any questions, please contact me at (425) 820-0100 or via e-mail at dave@miraiassociates.com. DHE: Very truly yours, Mirai Transportation Planning & Engineering David H. Enger, P.E., P.T.O.E. Senior Associate K0433205ESDvariance.doc ·~ ~ King County Road Services Division Department of Transportation KSC-TR-0222 201 South Jackson Street Seattle, WA 98104-3856 September 21, 2006 Cliff Williams, P.E. P.O. Box 2401 Kirkland, WA 98116 RE: Road Variance L05V0066-Talbot Ridge Estates-Related File L05P0007 Dear Mr. Williams: Thank you for your application for variances from the King County Road Standards (KCRS). You requested variances from Sections 2.12 and 2.13 of the KCRS concerning the entering sight distance (ESD) onto, and the stopping sight distance (SSD) along SE 192nd Street. A crest vertical curve at the intersection with I 02nd Avenue SE limits sightlines. We reviewed your proposal to reconstruct the vertical alignment of SE 192nd Street to improve the SSD to meet the American Association of State Highway and Transportation Officials' (AASHTO) minimums. A minimum 280 feet of SSD should be provided utilizing a two-foot target. This would require up to five feet of fill on SE 192nd Street, west of the intersection with I 02nd Avenue SE. I approve a variance to utilize AASHTO standards for the SSD with the following conditions: I. The applicant must adjust the driveway approaches to the realigned SE 192nd Street. Letters have been provided permitting the driveway adjustments on the private properties. 2. Clearing must be performed within the right-of-way (ROW) of SE 192nd Street to maximize the ESD for the driveways along the reconstructed road. The proposed 415 feet of ESD to the left (west) on I 02nd Avenue SE, exceeds the minimum AASHTO criteria of390 feet for the 10 over posted design speed of35 mph. Actual approach speeds from the west are reduced by the curvilinear horizontal alignment as evidenced by the measured 32.2 mph 85th percentile eastbound speed on SE 192nd Street. I approve a variance for reduced ESD to the left (west) with the condition that clearing be performed in the ROW to provide a minimum 415 feet. The available ESD to the right exceeds the KCRS minimum of 490 feet. The Department of Development and Environmental Services (ODES) will be determining the cross section for the reconstructed road and reviewing the engineering submittal for compliance with the KCRS. The requested variance for the proposed six percent horizontal curve superelevation on SE 192nd Street was not necessary. Your proposal appears to meet Exhibit No. \3 i\llAII\I FIL~PY Item No. L<::>'S:?O~t') 3 n l':, Received f · ~ ~ · 5:):1: t'I King County Hearing Examiner tliffWilliams, P.E. September 21, 2006 Page 2 superelevation criteria in Table 2.2 of the KCRS if a three percent superelevation is provided for the 360-foot horizontal curve radius. The design details should be coordinated with the reviewing agency, the DDES. This decision applies only to King County Road Standards identified in the variance request. All other design requirements in the KCRS and other regulations, such as surface water management and zoning, must still be satisfied for a land use permit application. The applicant retains the rights and privileges afforded by King County Code and adopted Public Rules pertaining to road variance processing (KCC 14.42, PUT I 0-2). This variance decision is valid for one year from date of letter unless an associated land use permit is pending or submitted within the one year period. In these cases, the variance decision is valid for the duration of the permit processing. A copy of staffs analysis, findings, and conclusions is enclosed. If you have any questions, please call Craig Comfort, Road Variance Engineer, Traffic Engineering Section, at 206-263-6109. Sincerely, c:p~-t1,o A) Dvyy\_~ Paulette Norman, P.E. County Road Engineer PN:CC:kc cc: James Sanders, P.E., Development Engineer, Land Use Services Division (LUSD), Department of Development and Environmental Services (DDES) Pete Dye P.E., Senior Engineer, LUSD, ODES Linda Dougherty, Division Director, Road Services Division (RSD), Department of Transportation (DOT) Matthew Nolan, P.E., County Traffic Engineer, Traffic Engineering Section, RSD, DOT Fatin Kara, P.E., Supervising Engineer, Traffic Engineering Section, RSD, DOT Kris Langley, Senior Engineer, Traffic Engineering Section, RSD, DOT Craig Comfort, P.E., Road Variance Engineer, Traffic Engineering Section, RSD, DOT ® King County Road Services Division Department of Transportation Traffic Engineering Section MS KSC-TR-0222 201 South ,Jackson Street Seattle, WA 98104 September 21, 2006 TO: Variance File FM: Craig Comfort, P.E., Road Variance Engineer, Traffic Engineering Section RE: Road Variance L05V0066 -Talbot Ridge Estates -Related File L05P0007 Applicant's Presentation: l. The Talbot Ridge Estates preliminary plat has 27 lots and fronts SE 192nd Street and I 02nd Avenue SE. Variances are requested for reduced entering sight distance (ESD) looking to the left (west) from 102nd Avenue SE onto SE 192nd Street, and for reduced stopping sight distance (SSD) along SE 192nd Street for the 250 feet of urban frontage improvements. A crest curve along SE 192nd Street at I 02nd Avenue S. limits sight lines. The King County Road Standards (KCRS) minimum ESD for the IO over posted design speed of 35 mph is 620 feet, and the minimum SSD is 250 feet. 2. The measured ESD to the left (west) from 102nd Avenue SE is 340 feet. Sightlines are restricted by trees along the north edge of the right-of-way (ROW) at the inside of a horizontal curve. With clearing in the ROW, ESD can be improved to 415 feet. With the trees removed, fencing and structures along property lines would restrict the sightline. The ESD deficiency is mitigated by speed reductions along the curvilinear road alignment and upgrade in the SE 192nd Street approach to the intersection. West of the site are cautionary 15 mph warning signs in both directions of travel. A speed study determined that the 85th percentile approach speed of eastbound vehicles is 32.2 mph. Accident report data for the last four years showed only one accident at the SE 192nd Street intersection. The ESD does not appear to be a factor in that accident. 3. The SSD over the crest vertical curve to the east of the intersection with 102nd Avenue SE does not meet KCRS. The applicant proposed two alternative designs, one meeting KCRS based upon a six-inch target and one meeting the American Association of State Highway and Transportation Officials' (AASHTO) manual SSD criteria with a two-foot target. A minimum of 317 feet of downgrade adjusted SSD would be provided. The profile based upon the six-inch target would result in reconstruction of I, l 00 feet of SE 192nd Street with fill sections to four feet deep. The profile meeting the AASHTO two-foot target would result in reconstructing 700 feet of SE 192nd Street with fills to five feet in depth. Note that both alternatives propose filling on both sides of the crest curve because the road cannot be lowered due to utility conflicts and the intersection approaches on 102nd Avenue SE. The applicant requests a variance to use the two-foot target profile because of •• 'Variance File September 21, 2006 Page2 extensive construction for the six-inch target profile. Letters have been provided from homeowners along the adjusted roadway that will allow for driveway adjustments for the realigned vertical profile. The applicant provided an analysis showing that the ESD and SSD for the driveways along the road reconstruction are either improved or equivalent to the existing conditions. Staffs Findings and Conclusions: I. Clearing should be performed in right-of-way (ROW) to the extent possible to enhance the ESD. The minimum AASHTO ESD for the 35 mph design speed is 390. Clearing will provide over 400 feet of ESD. 2. The design of the southeast quadrant of the intersection of 102nd Avenue SE and SE 192nd Street will be reviewed by the Department of Development and Environmental Services. The minimum curb return radius and transition paving tapers must be evaluated. 3. The proposed SSD variance with a minimum of 317 feet of SSD is more than the downgrade adjusted AASHTO value of 280 feet (Exhibit 3-2) for a 35 mph design speed. The two-foot target alternative for the revised vertical profile would result in fewer problems with driveway adjustments and result in a lower construction time period. 4. The Department of Transportation's Traffic Engineering Section files shows two accidents at the intersection in the past five years. In addition, two accidents were within 180 feet of the intersection. The proposal to improve the SSD should improve the safety along the road. 5. A variance was also requested on resubmittal for a non-standard superelevation design. This variance request was not necessary because a superelevation design per Table 2.2 of the KCRS can be provided. ~ ~(rJO ~~H--£-o ----, ~ J) ~\) II' IDesigD1l NilaD1lPJJail King County Depnrtment of Development aad EnvlroamentDI Sen1Hs 9000akcsdalc A-=Soutbwest Renton, w""'"-98oss-1219 meD1l~ / S~ll'Dcdlall'ds sftmell'Dftc-IReqllJlesft Project Name: Talbot Ridge Estates DOES Project FU& No.: LOSP0007 DOES EnglneerlPlanner Name: Bruce Whitaker / Trishah Ball Project Address: 19200 102nd Avenue SE WA, 98007 INSTRUCTIONS TO APPUCAl\!T/DESIGI\! ENGINEER: Phone: PE 425-885-7877 City, State, Zip Code: #101, Bellevue, Please be sure to Include all plans (T.I.R, ~ avallabla~ skstches. pholos and maps Iha! may assist In complete n,v1aw and ccnslderatlon of this adjustment n,quest. Failure to provide all psrtlnent lnformatioo may rasult In delayed procesalng or -at your raquest. Please submtt twp cgmpteta G2Pffll o1 this requesl applk:atlon ronn ang applka"'tft rae to the DOES 1-Counter, at 900 Oskesdals Avenue SouthMst, Renton, Washington 98055-1219. For addltlonal Information, phone Randall Panons, P.E .. at (206) 296-7207. RBPD TO SBC'r:t:OJI 1.4 IH CBAPTBR 1 OP TRB SlJRJ'ACB WATBR DBSIGII 1lll!ltmL POR ADJllS'rllBIITS DESCRIPTION OF ADJUSTMENT REQUEST: a Standard JO complex a Experimental a Blanket a Pre-application APPLICABLE VERSION KCSWDM: a 1990 (11195) • C 1998 (9198) llll 2005 • (Note: the term "variance• replaced by 'adjustment") APPLICABLE SECTION(S) OF !ITAl\!DARDS: Core Requirement #1 / JUSTIFICATION PER KcswfuR SECTION 1A.2 a Saa attachments fisted below. AUTHORIZATION SIGNATURES: DETERllllNATION: O Approval O Condlllonsl Approval (see below) 0 Denial 0 DNR/WLRD Approval Signed: Date: ____ (Experimen1al & Blanket wrtances only) ODES Slaff Recommendation Signed: Date: DOES DIRECTOR/DESIGNEE: DDES, Land Uae services Div •• Englneslng -Supcarvlsar: ODES, Bldg. serv. Div., 811& Englneartng a Planning Supervisor: Signed: Signed: Dato: F9'/D8/S1fmil-ADJ. '3oe P96/BltS/SIICHR-8.epy22,doo 11/17/,'J Cle Date: Talbot Ridge Estates -Adjustment Justification An adjustment is requested to Core Requirement #1 -Discharge at the Natural Location, Section 1.2.1 of the 1998 King County Surface Water Design Manual for the Talbot Ridge Estates project. Currently the site's stormwater sheet flows to the west property line to the rear yards of the adjacent lots which front onto 99th Place S. The drainage then flows to the south through an existing storm drain system on 99th Place S. Once to the south end of99'h Place S., the stormwater discharges through an SAO Landslide Hazard Area and then on to an SAO Erosion Hazard area. Drainage complaints 2003-0194 and 1998-0461 have been filed relating to slippage of the landslide hazard area at the south end of 99th Place S. After the stream exits the SAO Erosion Hazard area, it joins with Springbrook Creek, crosses under Talbot Rd. and passes through the Gallagher property, a trout farm with a history of siltation due to neighboring developments. Drainage complaint 1998-0045 has been filed relating to silt entering the trout farm pond. The flow then discharges into an SAO Class 2 wetland. The flow exits the northwest edge wetland and flows north under S. l 92"d St. and continues northwest. This point is approximately 0.6 miles from the project site. We have proposed a discharge location that will connect the discharge from the site into an existing storm drainage that runs west along S. 192nd St. The system crosses under Talbot Rd. S. and continues west until discharging into Springbrook Creek, converging on the discharge location stated above, approximately 0.6 miles from the project site. There are no SAO hazard areas or drainage complaints associated with this drainage route. The proposed discharge of stormwater into the system on S. 192nd St. fulfills all the criteria for granting an adjustment which are: 1. To produce a compensating and comparable result that is in the public interest, AND 2. To meet the objectives of safety, function, appearance, environmental protection and maintainability based on sound engineering judgement. For these reasons we request this adjustment to the discharge location. Page I or I :·-· ,· '.:,..;·-,,~,-, .·_:-:,.·:~·\ .. • ; '.<' .. 1 ·_1801,,1,~s· ' ~N I-' Jll , , , -. • 0 . '"."" -J <l:'i.J ,, ( ) . -., I ",;~ ' (' 'i ;c Lt6'1.11;5°J . ~ r.·' /j-.£ .,~•· J-"'11' C 1 ,. ---· ...=. -· :J · ~ ~~ l •""= ' Ji: -. l!!·f:! I:<"' ... ~ ' ~ \, I ?[>} . ' ,. "' • ~ I . "' -5 ' • I,-' ' , • ~ > ~r (2) I , •• ·-• ----ir~ ; 'g ~ .·1 ~-. . I , JSQt. ' I ,, ::i i" r,;;,, I ' .·, ,j ;,, ,... I til .... .11.!1.Y:.-.:::-:..._.-1a, .f/l r-·. i [q) a " i I) i,;i ', ::; : t~., j .r.. • ! , .L ui •:g /'-t.r110 rJ.J.9A: t · ~., ,:,: ·,"''-'--=~-=--="=J,-··---=::;--·---t>2.IJ4 ___ ; -, -,: · -~·-.:~-OB2• · ~ri:: <ti-'' i.-.~ ... , · ' "' 12 ~ '··-:r· 1---· ______ -_-,_:·--.::'= .. ---··=·=-·~--·=·"·=:cc.:::.-·-· ;r.. .. ,. ·-· ·l h,e~ ..c.·,c,· . ,1 .21 ~ ; .Jl!l!.,, @·:"". ~-···.! ... . . ·--~~-..... -,1·--······· -·-----~ _·-·'"· .-.:. 'ifi r:::.·· __ JI_;. -~a-Rf"),.<i-+' ···; ' · · --···-· -,· _ . ~1;1 i:rr·;;1 '1? !S. , ,. m.• .. , ~ ,·,:·1 i 'I ;,,,_.,---,., .. , -• • .,· f -, . ---... ~/~.·-····•-· ~! , .. . . ,. !£ i, -i ! ,• .,. ' ~ i\ .. _..,5.0h,., --~-,~ -; (':!' ,-['901;\' (•) ·1 '·u'4 N I 2 I ,i ~,r '01: I o,m ff,·"' : "-·'· ji;;1ilr"' : -:· 1 · L,J 4 71 ::.c ·;·tjl • ~ ~ '!I • r~:~ ~!! 60 ~ ., • . A'l!: \... . :s i~' __ ::z • -:' ! (i.·)"t,!ii , ,·"'._, •·+' .. ; 7 :·1•l ·.,a· ,i ••' d 1" '' •· : 1}1:::-=-:::..-=:: ~-::.=;,-...:-:=.:· .::=~=,,,-· --.-· __ ,. ___ . ____ . . .. ····-·-. ~~ :-<_·:, 1;,'F:1} ... it. L.,' ... :,t&_,.J jf....L~-, 1 . ·,.J11 • '"1 ~-· ' ;; , .. ,' .•.. -·-···' 5$1, ····-····---· ---· -·· ·-1! '. •.· •. ;,!J'V"' N' 1;() ~01.. l< ~' 1 !i.2 ,, (~f L ,....:,,\ 526 ------·---··-~j~-~ _ ~--33441'.,. ......... ,.... . .-=~ ~b,: .• t: · :ni1t1 .;:;~; ;,;.,._ J,.,, 6 <c."' •• • r· 6.¥. ~ . tj_ !1~ . ·"·t·"\:. I H·f,7.~,:,. :i, ~ t~-.... ~.:,;, ,.,,,, --~. ~ ~-:-"(m,-·,,.,7i;;.....,;,? 1!,':t:c-11· ,f#!>·!'~-t! ~~~t\u·,~:1 ~~L-*" ' t·· "' I • '' · • I ' <?-,tr•'lt'-'l: ':S ' ,i ... ; ' « · • ,01 • ., • ~silo ! 1:::, . . ! . , ,J '•'-(2) :J,. • / l';''.r·~~ r ~ "i ,If ~ ,::i,, "'; ;--;;;:.· ;c··r..-·r,,",:~ ' •':'.° ' ,-, _ • -.··· · · ?. 68A. ( 3i cf' 0 /Y ~ ~ .. · ·1 •.• rii1 ". ·~15 ~-,;l·' '· ·ll :i" ''·' 1 .·. , 1, 034 ,.... :t. 2 50A-.,...t-, , , · .(: ~ tJ ~ ,... -t ... -; 7 ~ •"" ~=-_... ". i !) ; 0 ,,2~ @· [ . . @\ t . ,~:.?,· ~ -·'. : =\/ i /;;° ·!,:& ~.,, J <. p,, -• ', "'"°':"; !;,; !Os,/ 12r,~',;_,;; .,/_I QiJ\li!i Om1onoe ,/ ,:.:1r···-·· ·-····-··-···--··-"'" ! ;/!9J.;· FJ._i, '=/W" 1'1·r ... o.;;',r,!-sj ·~"' ... ~·,,,.·.m:,kl·.~ rr r-;;,<!0. 1 {S",CfS',f/U~ i_:,.::. 1 ,, ·• __ .. -·-;;·;;;.,;·1 ···-·-'···,;i1 --·-·:·-_··---:?il.~--, -~-J""-iJ.·...,.,,--f. ... _ -~ -mr-----::;:·-; 211 r1\,c, s1·,., r·· D lf'JAf•'A"'--Do•~ 1::,.l pn""PO'~,ro . 2'5Ac' '8 ijf· Tlb5 t...21.,! ,!O ,,.,.,,, il 121.t'.&I• :H j :1 -FV1~, '3Cr1'-, Vt£.. i\Jf FI-U ->~ :: ... ,. 1i.~~ S.~OS; 5!~~ · ·liJ1G ...... .,.,"'!;I' }._,,', Q (!} d·='i :-,j/,;; c.lD" 'V""'° ~ ~-..,. I '··· . "'AAI "f.Q. ,_,.,. V':;. . ,, ,.. 9 19 ,'-e "1· --_, iilliil x'\t 1 ·• ....., "°""'"'°""-"''~ ! ,\ i ,• Y rtRt.V"-_;~ (!i') 'la ). "" ,,,/ ·,, . ~ i ": '.t·, 0 ·;:,C,¥2 -l i ';'~ , ~ ,. __ !".IC (4..,fJ n fl • i1. ..._..,. '& '" " I~ 4 QU ·30• ·• "' • •·.·> ·i''3 / ,..,,.._. S • r.1'-•. p'·' E ~.'>:~ '· / ·'""· I ,.. •.•. 'c .. ~:, •i, ,J::, <~ • i ,,:, V I ._ ; • I • r"· • -~ " ,l'/ """"' ' ~l ' Wo.,=. -· ~ ·al ~ . }c;,,a/'i ... , ;;,,; j \ f"l ~ , . Z ' ,~ • /-.. ,, " ,. ~• ! ·---. ~ ~'let-·-'{;:'~ :nr 0 &J .. &.~ Q :·:! ' .. '_l,.; I' ~ ~0~ ,.,.._ ':-!-.,I \;~ ';:.01 ' : 1J i !5) _· I · _ :=!5'; · I I ! '-t;. 4;'1 -"-~/i ... ?4' ~ ·~.' .,. (,~.~ ~ ~~ ,...._ w• ...-•~.:,I ~--·--· -~---·· -· -·-0-s>o. 4 ~ .• ·, . >, . . · ', ,.J jf 0 o Ir .. , ~,; J. /' -,~ ", . ~. ·,if ·• i. " j , .. ~' • 1, -l <:~ ·'·ro, .•.. ·-·. . . . -tL *"·$-· . ,.,,, oo Q .,. ________ Of)O if .. Jil,-; I ooo • 0 I <1"~ '0.... ~ ... Ill \~ ,,_,, ~ "./t'-,,, •• " ~142' '"' 0!) ' . I· ~, .. :.:--":'.~ :·~ ~~~-~ __ ~.h"A'.~;.~""; :.:; ,-.,.,:_,. ···~--~-~ -l . · -::::-....... .: g-· --......... ' *f "' f'"il / • • 6~:i'':-~ ~'> ~ fl~ :--, '· .._1},• ·, =,:/:;... ...... _.fr53.~S 'J.-1 'i 'T:;,; !"';"! : 's'IZ .;{ : : ·''""~---~"""'~-"·.-=i-··~=---=~S .. ;r·_··..ci, q2·'~·0··-c. · .. ··-···=,-····-~·--_--. !lti~~ q" _A,,,_·.· "9'ji.,J'jii ,2 \ / ~4 ~"' -11 ---~'lo .• .,,. ____ ,,,,_ __ L,.,..._~~.u., ... liL .. -·.'-· ~ T ~J<.. ~ ,-~ -· "".31[,.<:'L"":.----..=:.i-i::::;~-~?'l,J(<C r··~~~ -g 9--..Jl:l' '-'••~ ·--.,.~ • .,..__-,, .--.-~-· -, • ~ ~ .. ' -~l-·1 ~'--~ "·-,., --~ • -.·. "i' r.., c-~ ·• · , c:C --• "t !:9 B t.';•~1-~oc·;;-c.!-e<:'.-t--4';-,,.,,,;ci ._,._. · '· ., , ~...o -,. ' ~ " ,~;;; ··~--· --·· · ' I I 7. .. ,. ,., ,., -""t,{~ I ' -' u -: , ·1,.,'ftc~\ t~A~" ._ "'1 , i ·« . . ~~ ... . -1~;,, .. .. ! ,. ' ·--'"'-... ,I L . :#1'-/I DI: ';.c ~ ,,· ,'~) I , .. . \. ,, . ·. ·, /'-, , . .,.,."'..: ;!;'I.'..,.---· ... -.. ~1 ,:: rJ , ,:' -·til-" \ "'-C •• _ • __ :,,,,, ............ ·-·: , ,,,, __ K '< '.. ··" / "[;: I 1 :.1 ~i. 2 ,.,,, .r', APJE',·)E, 1 23Hi.1 1C:-~ · ~ 11·! <:a·3,3,.-;;;c,: ' 1 '';;' · ,., ,, · · ·, x' ,-/ . ___ ,ID _.,, .,. 1 ,1: -·If?,~ ,.,-·., •'.ls ·,. !·, t, ,·· , •ie: ";;'.I , . -•· , '° , xli. ·,, .. /' _,/. . . / -~ I0.64A,: :~ f.;, I l''Q . ',t,' '. ~ •. .,,, .,, ~ . 1, ,,.: ,~· I• . . ' ·~· ' -~(• ·-· H-"""" '· ,._ ~-r,i ,.·. '. ' ·1 'n :--~·,:,1 '"' ;,. -··/-.. -·--"/ ,,, , Pt.: ! I ·, i" ,in , ,,, 17 '';;; ,, ~ ::,,· ---· • ,/,:-• --ii '. ' ''' " ,,,. ,,//,'/ -'!!.... 0 .,1, 11 , , ;,-, ,,S'<C ~'"~~.,,'\ ... ,ak~""9W 8-~ i'f\ ... ;: . ..:..·0 '-·---<ril~;z.l k ~ • -, ' / ' I'-,.,,J fil I •' ,,t):!_ i;,.,., I ~"<I ~-p,'"':,_.v c'L• '!I, •r:i-·T~,.... ~-,_, ;/,;-· -,-·--•. ..-1 •. . .•-. , •. , ;' , ..._,. , ~/ / ,-1a,, ;, ,i ~ I ' '>i' ~-"", .,;o;. .i:i It ff, , ' "' ' ' '"' · ,-, ".•:J._, X •• ·. 0'·. h. • .,.,... ..--, -,,,;n; i ". -, ' .. f ,,,o•,!;1 .,f.' ..,.,, 'ioo.lc--\ 1,1.,.,l,,..1"'1,....., ,,Sm ,.J I,~ /~. ' · ! ' ll'.i~,j P 1 ' ' _,._•,;;;~'1!//,,1 '" •; , . .,19 r,. \ , r-·~,iij er· ·tmoi. S: 1 I"' « -.... ·, ~-·-' __ f1,,• l 1 ,1 .t.'<' ;;,·:.,rr, c,,t, ·.,11~ i2;@,~ ,t li!t -r.. . .-;..::...·-~=~' ~-·,:i:l !I • ? j .. ~ .• -.%. 'ny-~··s·,.-,.1_15.J~ro e:l'l:'11it. ·"'.~•!Ml ;, '·esr.;I 1 .,,,,,~· ,, ·1 \'\ l,;h'! t! ··. ,S,'3 ;-·<6-tW~i.r ~~-,~.,_,,__._,_.-1 ~---.--J:~; ;l -... . _d.tj t __ ..@fill_ •.• ~ .. -.Ji' pt5 ./ -~·~ 4 'I' .• ---· ....... ' -. ~l ;,l -~ . ., : ,. • --· n · · l' ~ ... 1011:rs "1 ·; 1; ,_' ~ • 1 ,, !!li n I i;:.,..,, -· ,. •••. . -. _ .::i 1 ~ · .. · ......, ,,, .;;ti.::~,....,, " A •.·:, ~ ·t:, ·,-~·:ii ".. ,1 . ,!, tc.~_;.1Jy\."'~-~ r:· Ii:"" .r:~-· -,,~ '··~·, ,,'Ii ,--1f36 !i i· " t2!: "' #\ J :1i;;: • I · ,,~ "~ ·1· -<>!'. l 1 -' -., . l"'"""'·' ·· ~"' i , / ,~ ·· " '"' •"· If "' ' I . ..., ' r\' "' ·, ~ J '·--~ ~: 1, A: ~ ' _,,... ,,'~ J:"'"" ~ l. '°' · I~-,~ 11 · ;,21 ,Jf ::5 i<!f !ti,.• o·•·"I'" "' -.... --· - ..:c"'-1·1' ~ ~ -1._,.:.,.;.r • io.L(\'-j ~""!:-"-'~'~>] !" ... (_t ,~,St ~; ;;: ;~ i' ' • '-'I -~-1"'-1,-" -·r--•-~ :, I l----,..T ~"'£:..-J. ;~,;r ~ i ,•: ''.iS\ , 4 ~ ~ !, tt, ,. 7u-1 112 -_¥f:r.o !~ lii15~ 'f.._, l~«rl · .. o, ~--j ~-J '{ ,. J: .. ''J , ... ~~ i ... _ ------,, .• "· , o -0 •., , c,r.,. ~ iVf.' ~ .i"' \ 7? /11• '· '-°'' · --------·-.. ,..._ .,, •. l'\t N 11'1 ' , DIIAINI\G,E' "'. ; i t ~ "· '-•· ,;l ., ., _,i, '17jlil!\ ' ~ Zit• lf1.>li ·-' .; ' ® ' 'El ''2'\£"'.'~ ·:: ~ :,· ~i~ '<if ,I -' ·-·-..... , .. , c.DI'<-... ,,.,r ~,if, (\ .,, ,S4T'-, . ~.,'\ ~~11!11 ~ 46~ ·-·r· "'"' ~, .... "-··--·-·-;· -. .....!.&~--~,-.;:,.,_,::,-.:c-:~s~ . I ... , ,,.rM I(""~ -_ ... = ,~~~ .... .,,,.,---.. -,9 .. ... • • ;:"\; l;l--~..... . . .. ·-·· r ,,1,"' ........... ~f=;, --,..~~---·-r,~-., ;:!.~----' 7' • ~ rJ l<\.Dil~..._,-,~ Jill"",. 't 11!1 , . --4 ' , 1 .___. I ,.,.,,.P,a::;; ::i I _., I ~.1 .,,So l Cl 'Ul} O oo~r , ~ iii\ t. ~ e J., '!' jl ... '.. •< ~ t, ~~-. s ,a ,'.fr J°ll'r"j;j--,,fil\)' ~; _s ' • ~ f:...:.:::_::._:...,::i i ;n,,, , -. , iR H~O-* • .. • ~ J•I ~ 1 I -~,6 ''Y' \, ~· : :.. •: ' ' ,; : . ,. ' !-7-•• .&-.... "' f--M~=-:.j I . \,; • • (f';:,;;, ·,:tE~ • '{iL " O I ;:;. ·; "' ·.,( ,. • . .; \~ A' '. ,, tJ\.'-t·. ,,._,., ··1., I .• 4 .•. ct. ~-•.• ,.,._-r i.'" .'·1·, ;:, .t~ ··-J:.,··' ~ .-,,..~. ·7;;; ·- -~,~ ··3 ~~~!., -~-· --. · tJD :;-.., ,,_ ~ -~·-"'-"~ ,. ,,r--,,~~ i . ; .;.-1 . ~-:-.. }f::, -~-t'I"~. U, "·, -,·· ' ;:< ·~M""'~ {-~ ,,_,.,,~ l. •·· ~,·,. -~ ·, . , ·. ,,,.,., =. ,.,.. I _.. · · ·· .,... '" ... ' / / ·· -· -· ~, I· !,.,)'.'.'5 ,{yC <i' .:,... . •'•:S' ..• ' :~·> :• . ' ...... .· /.. -' Sf/ .. J ~ f ~~:-.:~-·· .. ~ .·.-. . ··~. -· '.>'-?•", " -~ / ,,..,. l:~ f l:i ) . ')-~ .. ~ '.'" ·, ... :· .... ',... ·.... ~<£:".--~ . " ' . / /~ ./ ·' . / 1 t,q ff ~.•.\i\ '·, '•,. '( C,·~e '. '.,'.IS,,,.:~ _ '\( ./ / ~'. , ·'-· i ':,_ ..... ~ {\ r •I,_ 'it;t.•", ">., '\. ··~'-' •• ' 7-1 • ; t,) t·-. 1;: ~~i' ', '··. "'· ·, ·= .• 'l -e'"' / ~ , / ·' / I J:.;!', ~-',,-.. ,---z,.""" ·... ', ', .... "·/?r .. g II" ll!"l<PPY-')< ! J.','."/' '_:,.·(i"· \ ...... "3/~.;:~........ "'· •.. .._ '· '• ~.:~ ··~ . ~rt,t¥fVJ~Bft6f>e. ..... / I __ f.' __ if / ·-.,~ \ ·,. -~--:.; ,·// •• S ""O k-o o,.,.,a p. ~-,\'. . _...,. · HA-, .ti,,,,~--;_;,, . · · • , .. , t ~.., · "n ·• • l""'i '-"~ -' ~ -...~ c:!-R"6;U •'.st f . .() J-··· ---· '·ii<~:, ·, '•<::l;.q,1;1....;'-11.~9,>,..a~ <-Ke/i "~~'.'> "• / ./, J;Vlff>~~ // .-! ,, i ·~ ,--~lf.:'V f'\\. -.;,,. ,..,....,. ~ , I"\\ 6'~&\\ ~/ -~· -iA·;l"-/.... ,,;j'~.,,.: ~..,,, ·-~,, ,, ........ ·. , ...... ...._ .... _ -..::-..,;~ .-7:.;-;. . ·' -, . o . ., •, ~' ' ' • i~ ~ ,J~i ,.:4,:,. · ~--".--.-:-: • " • "G;;~-"-. ~"f' ", .... ,_ . ".,, _ ~ . , / ~ ;:- .'io·!::: -~ :, , !!. . ' ~ • .... ' . '_, . . / ~ <-d ..a. '·.' tif'.' i.P ~-'~ I ' • ~',: • • .f'\:, 'l.. ~ . , ", "' ""-" : / / ' '>,. . i,.:, .' -/· -, , · .. ,, "' -~ '·-~ •. , ~, ~ ·. / ,sc,,.(, -''"''!ofJ·i . '• ·L ·. "~ ' " .,. ?.".° .,.,7,.., , :. , . ..._ >t • 'P ."" -~ '. , / ·,1:l°' --· . -i /J ! !,y ) '; ·, f,', .,~t/ ,, .. .,, l ' • ~ "' . • • ........ . : '-·-\, •. -· . -• . .,4".-...~ . .... . ~--~ .... A . . -. . . " NORTH SCALE: 1"-200' DOWNSTREAM DRAINAGE ROUTES TALBOT RIDGE CORE PROJECT NO. 04120