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HomeMy WebLinkAboutTract 29053, 32974S. E. Medall & Associates, Inc. C Consultants in the Earth Sciences 3030Soute Bundy Drive, Los Angeles. California 90066. 21313W4079- 2168Sout11 Hathaway Street, Santa Ana, Cali tornia92705. 7141546-6602 17231 East Railroad Street, City of Industry. California 91748. 2131964-2313 SOIL ENGINEERING AND GEOLOGIC REVIEW OF TENTATIVE TRACT 29053 AND TRACT 32974, DIAMOND BAR, COUNTY OF LOS ANGELES, CALIFORNIA FOR WEATHERFIELD HOMES W.Q. 605 October 4, 1976 A I S. E. Medall & Associates, Inc. Consultants in the Earth Sciences 3030 South Bundy Drive, Los Angeles. California 90066. 2131390.4079 2168SouIh Hat hawayy St rest, Santa Ana, California 92705. 7141546.6602 17231 East Railroad Street, City of industry. California 91748. 2131964.2313 October 4, 1976 W.O. 605 Weatherfield Homes 2130 East 4th Street Suite 110 Santa Ana, California 92705 Attention: Mr. Glen Brengle Subject: Soil Engineering and Geologic Review of Tentative Tract 29053 and Tract 32974, Diamond Bar, County of Los Angeles, California. Gentlemen: As requested, we have conducted an additional soil engineering and geologic analysis of the above referenced tracts. The purpose of this investigation was to re-evaluate the soil and geologic conditions with respect to the questions raised by the Los Angeles County Geology and Soils Sections in regards to the previous reports on the property. Revised preliminary grading plans have been made by VTN Consolidated, Inc., for the first unit of this tentative tract which will be Tract 32974. Scope of Services The scope of our investigation consisted of a review of all the previous soil and geologic information for the tentative tract, a review and comment upon all the review letters by the County, and Weatherfield Homes Page Two October 4, 1976 W.O. 605 additional subsurface exploration as requested in these review letters. All of the previous investigations and review letters are .listed in the Appendix of this report. All of.the geologic data for the first unit, Tract 32974, of Tentative Tract 29053 has been plotted on the preliminary grading plans. For the remainder of the tentative tract the geologic and soil information from the previous investigations and from our additional investigation have been plotted on the approved Tentative Map. Both maps along with additional geologic cross sections, stability analyses, and the logs of our borings and trenches are included in the Appendix. our additional borings and exploratory trenches were placed in order to obtain additional subsurface information regarding landslide depth and limits and to confirm the presence or absence of questionable landslides. Discussion Utilizing data from the previous investigation and our investigation we have constructed additional cross sections in the vicinity of the landslide at the extreme north-eastern edge of the property below Lots 72 through 75 0£ the first unit. The depth and lateral extent of this landslide have been defined by exploratory drill holes and 0 S. E. Medall & Associates, Inc. weatherfield Homes October 4, 1976 Page Three W.O. 605 test pits which were excavated in our field investigation. This slide is depicted on the preliminary grading plans and is considered a separate landslide from the Diamond Bar landslide which is located in the Equestrian Area to the northeast. The thickness in relation to the existing and proposed grades is depicted in Cross Section A -A. This proposed fill slope to be placed upon the landslide below Lots 72 through 75 would create an unstable condition. Therefore, a buttress in conjunction with placing fill in the canyon at the toe, will stabilize this area. Geologic Cross Section B-B was constructed through the highest cut slope, and the fill slope above Diamond Bar Boulevard where fill would be placed over a dip slope condition. Both slopes in Section B-B would be unstable as designed without remedial grading measures. Geologic Cross Section E-E was constructed across the property in order to depict the overall geologic conditions from the ridgetop to Diamond Bar Boulevard as requested. 1 A questionable landslide was previously mapped in the vicinity of Lots 118 through 123 and 131 through 135 of the first unit. A boring was placed on Lot 135 to determine the presence or absence of this questionable slide. The boring indicated that there was no landslide debris present. The basis for calling this a possible S. E. Medall & Associates, Inc. Weatherfield Homes Page Four October 4, 1976 W.O. 605 slide was apparently topographic. Down -hole logging of the hole re- vealed a 2 foot thick concretionary bed at a depth of approximately 27 feet which we consider to be the cause of the change in topography similar to that type expected in a landslide. The depth and limits of a questionable landslide below Lots 11-16 of the Tentative Tract (not within the first unit) were defined by additional subsurface exploration. Stability analyses of this slide were not conducted because the grading plans for this area are being revised. Remedial measures required in the first unit (Tract 32974) are tabulated in Table I. The question was raised regarding the stability of the entrance road with respect to the Diamond Bar Landslide. All evidence of the previous investigation indicates a direction of movement for this slide toward Diamond Bar Boulevard and not toward the subject tract. It is our opinion that the entrance road to the project is no more jepardized by its presence than Diamond Bar Boulevard and that the probability of renewed movement is to The only remedial grading recommended would be to remove the slide debris present between the entrance road and the tract boundary and replace it as compacted fill. Buttress Cut Stability As is the case with most buttress cuts; gross stability during con- struction is very low. The backslope angle shown on the stability analyses are the maximum angle required to obtain stability in the S. E. Medall & Associates, Inc. Weatherfield Homes Page Five TABLE I BUTTRESSES Location Cut slope rear lots 29-37 Cut slope rear lots 47-52 Cut slope rear lots 86-102 Cut slope east lot 82 & 117 Cut slope between lots 81 & 82 Cut slope between lots 84 & 85 Cut slope between lots 85 & 86 Cut slope between lots 86 & 87 Cut slope rear lots 130-136 Cut slope rear lots 154-158 October 4, 1976 W.O. 605 Geologic Condition Daylighted bedding Daylighted bedding Daylighted bedding Daylighted bedding Daylighted bedding Daylighted bedding Daylighted bedding Daylighted bedding Daylighted bedding Daylighted bedding FILL KEYS Location Fill slope below lots 1-5 Fill slope below lots 6-13 Fill slope below lots 14-21 Fill slope below lots 22-27 Fill slope rear lots 37-46 Fill slope rear lots 72-75 Geologic Condition Dip Slope Dip Slope Dip Slope Dip Slope Dip Slope Landslide & Dip Slope 3' below bottom of slide, refer to section A -A. Key 140' x 3'-/ 30' x 3' ? , 30' x 3' / 15' x 3' 15' x 3' 15' x 3' 15' x 3' 15' x 3' 35' x 3'/ 30' x 3' Key 190' x 3' 60' x 3' V/ 40' x 3' 35' x 3'" 20' x 3'-// J 125' x 3'* S. E. Medall & Associates, Inc. Weatherfield Homes Page Six October 4, 1976 W.O. 605 completed buttress. Flatter angles may be necessary in order to actually construct the buttress. The actual backslope angle is left to the discretion of the contractor as long as the maximum slope recommended is not exceeded. Laboratory Testing The previous investigations have established the general physical characteristics of the on -site materials, therefore, only limited testing was conducted during an investigation. Moisture -density determinations were made for each undisturbed sample obtained in our exploration. These were compacted with those of the previous investigations and found to be similar. The results are shown on the boring logs. Samples of the typical site materials were tested to determine their shear strength as compacted fill. Direct shear tests were run on samples which were remolded to 90 percent relative compaction at 80 percent of the optimum moisture content. The samples were allowed to saturate and then sheared at different vertical loads. The shear stress was applied at a constant rate of strain of approximately 0.05 inches per minute. The values obtained for and c based on yield strength were used in our buttress designs. The results are shown on Plate C-1. Method of Stability Analysis The typical slope requiring support by a compacted fill buttress is a slope composed of layered or bedded rock in which shearing strength or IS. E. Medall & Associates, Inc. Weatherfield Homes Page Seven October 4, 1976 W.O. 605 resistance to sliding along bedding planes is much lower than the strength of the rock or the strength of compacted fill composed of remolded rock material. This directional weakness is due in part 1 to a tendency of the rock to separate rather readily along the i bedding 'planes and in part to the presence of thin films or layers of especially weak material on or between beds in the rock. Where the surface slope in the dip direction is steeper than the dip angle, down -dip sliding along the inclined bedding planes exposed in the slope is likely to occur. Such a slope is illustrated on Figure 1. CK = 011any Figure 1. .Typical slope in adversely dipping bedded rock. Down - dip sliding may occur along any exposed bedding plane. All that is necessary is that the down -dip component of the gravity force (Fs) acting on the material that rests upon any given bedding plane exceeds the available strength of the material or the resistance to sliding Rs) along that plane. The resistance to sliding has two parts, one S. E. Medall & Associates, Inc. Weatherfield Homes Page Eight October 4, 1976 W.O. 605 of which is a function of the component at the gravity force that acts normal to the bedding plane (Fn). These are shown on Figure 2. FS= WSina IW Y RS= lc+F tanQ M Figure 2. Resolution of forces tending to cause or to oppose sliding. The parameters c and that appear in;the above equation define the strength of the material that is present along the bedding plane under consideration. Since it is not possible to determine with certainty the values of these parameters for each and every bedding plane along which sliding might tend to occur, it is common practice to assume the worst, that the lowest values obtained are characteristic of each and every bedding plane. This assumption is generally conservative. Furthermore, it is common practice to use effective stress calculations and data obtained by prolonged shear testing of saturated samples to establish the values of these parameters. This approach to the 1 S. E. Medall & Associates, Inc. Weatherfield Homes Page Nine October 4, 1976 W.O. 605 determination of stability is also conservative. A compacted fill buttress is a mass of compacted fill that is placed against a potentially unstable slope for the purpose of preventing slope failure or improving the stability of the slope. The fill is generally wedge-shaped in section, its variable width being designed to provide resistance to sliding or shearing where necessary. A typical buttress is shown in Section on Figure 3. face of l7Vi'i'r f.55 1 ComPacfed 0 bedded hoc /C aoe Figure 3. Typical configuration of compacted fill buttress. With a compacted fill buttress in place as shown on Figure 3, the surface along which a bedding plane slide might tend to occur would necessarily curve through the compacted fill or through the bedrock crossing bedding planes) as shown on Figure 4 which follows. The stabilizing capacity of the buttress fill derives from this fact. The strength of fill and the strength of the rock in any other S. E. Medall & Associates, Inc. Weatherfield Homes Page Ten October 4, 1976 W.O. 605 direction are both much greater than the assumed resistance to sliding along any bedding plane. Figure 4. Potential paths of slide surface. Buttress design is a "cut -and -try" procedure in which a trial section is drawn and then relative stability is determined by calculation. The buttress width is increased in successive trials until the calculations indicate.that an adequate factor of safety can be provided by construction of the buttress section tried. In order to shorten the design procedure, several simplifying assumptions are commonly made. 1 The method of analysis used to evaluate the stability of recommended compacted fill buttresses was developed for use in Los Angeles County S. E. Medall & Associates, Inc. Weatherfield Homes Page Eleven October 4, 1976 W.O. 605 in 1962 and has subsequently been used for the design of hundreds of existing buttress fills in southern California. Essentially, it is a simple sliding block method of analysis similar to the standard 1 method that has been incorporated into the Los Angeles City Building Code (Section 91-3010). However, there are significant differences. The geometry of the potential slide mass selected for analysis is established by: 1. Assuming that the most critical potential slide surface can be approximated by two planar surfaces, one of which is horizontal through the toe of the buttress fill slope and the other of which is parallel to the bedding plane dip,. -intersecting the horizontal base plane a distance back from the toe of the buttress slope and distance.equal to 1/2 the height of the slope. See Figure 5. 2. Determining a critical depth (dc) at which the resistance to sliding (Rs) is equal to the component of the gravity force that tends to cause sliding (Fs) and assuming that the potential slide terminates at that point. dr- I Figure 5. Geometry of most critical potential slide maps for analysis. S. E. Medall & Assoclates, Inc. Weatherfield Homes Page 1 - References October 4, 1976 W.O. 605 1 Previous Investigation of the subject property and adjacent properties. Engineering and Geological Report of Landslide, Diamond Bar, Los Angeles County, California, Geologic Supplement No. 2, by Richard Merriam, dated October 16, 1961. 2. Preliminary Geologic Report on the Equestrian Estates, Diamond Bar, Los Angeles County, California, by James E. Slosson and Associates, dated July, 1963. 3. Addendumi,to Preliminary Geologic Report on The Equestrian Estates, Diamond Bar, Los Angeles County, California, by James E. Slosson and Associates, dated.September 27, 1963. 4-. Second Addendum to the Geologic Report on the Equestrian Estates, Diamond Bar, Los Angeles County, California, by James E. Slosson and Associates, dated April 18, 1964. 5. Addendum to the Geologic Report, Equestrian Center, Diamond Bar, Los Angeles County, California, by James E. Slosson and Associates, dated May 15, 1964. 6. Third Addendum to the Geologic Report for the Equestrian Estates, Diamond Bar, Los Angeles County, California, by James E. Slosson, dated November 1, 1965. 7. Fourth Addendum to the Geologic Report for the Equestrian Estates, Diamond Bar, Los Angeles County, California, by James E. Slosson and Associates, dated January 6, 1966. 8. .Geologic Report on landslides adjacent to Lots 29 through 36, Tract 30298, Equestrian Estates, Diamond Bar, Los Angeles County, California, by F. Beach Leighton and Associates, dated September 9, 1971. 9. Engineering Geologic Report, 256 acre parcel, Diamond Bar, Los Angeles County, California, by John D. Merrill, dated December 1, 1971. 10. Preliminary Foundation Soils Investigation and Geologic Investigation, Tentative Tract 29053, Diamond Bar, Los Angeles County, California, by H.V. Lawmaster and Company, dated August 28, 1972. 11. -Supplemental Engineering Report, Tentative Tract 29053, Diamond Bar, Los Angeles County, California, by John D. Merrill, dated August 29, 1972. S. E. Medal[ & Associates, Inc. Weatherfield Homes October 4, 1976 Page Twelve W.O. 605 By reference to Figure 3, it can be recognized that the higher a hypothetical slide mass is, the greater its mass and the gravity force acting upon it will be. Accordingly, the selection for analysis of deeper potential slide paths (See Figure 4) will result in the calculation of increasingly large sliding forces. However, if the potential slide plane departs from a planar surface, the available resistance to sliding increases due to mobilization of resistance to deformation and shearing within the potential slide mass. This resistance is generally ignored in the simplified sliding -block type of analysis that is commonly used for buttress design because it is very difficult to evaluate. However, it is a real resistance that becomes increasingly significant with increasing depth and curvature of potential slide surfaces. More rigorous analysis of stability in which this added resistance has been evaluated has shown that the most critical potential slide surface is a curving surface that is approximated rather closely by the assumption illustrated by Figure 5. This is the basis for the assumption. Using this assumption but neglecting to calculate the added resistance is still conservative. ISUMMARY This reportwas prepared to aid the project designers, reviewing agencies, grading contractors, owners and other concerned parties in 1 S. E. Medall & Associates, Inc. Weatherfield Homes Page Thirteen October 4, 1976 W.O. 605 completing their responsibilities toward the successful completion of this project. The findings and recommendations in this report were prepared in accordance with generally accepted professional engineering principles and practices. we make no other warranty, neither expressed nor implied. The findings and recommendations are based on the', results of the field and laboratory investigation, combined with interpolation of soil conditions between test pit locations and data from the previous investigation. If conditions encountered during construction appear to be different from those presented in this report, this office should be notified. The opportunity to work with you on this project is appreciated. Should you have any questions, please contact this office at your convenience. Respectfully submitted, S.E. MEDALL & ASSOCIATES, INC. ARTEDI B. CORTEZ R.C.E. 26009 ABC:SEM:db SHELDON E. MEDALL C.E.G. 51 Enclosures: Preliminary Grading Plan Tentative Map Boring Logs Trench Logs Direct Shear Test Results References, Geologic Cross Sections Stability Analyses Standard Grading Specifications c: (2) Addressee; (4) VTN, Consolidated, ATTN: Mr. Jack Staley iS. E. Medall & Associates, Inc. Weatherfield Homes October 4, 1976 Page.2 - References W.O. 605 12. Addendum Geologic Report, Tentative Tract 29053, Diamond Bar, Los Angeles County, California, by John D. Merrill, dated October 10, 1972. 13. Addendum Geologic Report No. 2, Tentative Tract 29053, Diamond Bar, Los Angeles County, California, by John D. Merrill, dated January 10, 1973. 14. Preliminary Geology and Soils Engineering Report, Tract 32320, Diamond Bar, Los Angeles County, California, by Lockwood Singh and Associates, dated May 3, 1974. 15. Geologic Report on reported landslide area above Diamond Bar Boulevard between station 65 + 00 and 75 + 00, Diamond Bar, Los Angeles County, California, by Richard Merriam, undated. o Los Angeles County Review Sheets 1. Los Angeles County Soil Engineering Section Review of Preliminary Soil Investigation.by H.V. Lawmaster, dated August 28, 1972, Review Letter dated September 28, 1972. 2. Los Angeles County Soil Engineering Section Review of report by H.V. Lawmaster, dated August 28, 1972, Review Sheet dated December.28, 1973. 3. Los Angeles County Soil Engineering Section Review of Preliminary Soil Investigation by H.V. Lawmaster, dated August 28, 1972, Review Letter dated September 28,•1972. 4. Los Angeles County Review Sheet, Geology Section for Reports by John D. Merrill, dated January 10, 1973,,August 29, 1972 and December 1, 1971. 5. Los Angeles County Geologic Review Sheet for Report by Lockwood Singh, dated May 3, 1974, Review Sheet dated August 22, 1974. 6. Los Angeles County Soil Engineering Section Review Sheet of Lockwood Singh, report dated May 3, 1974. Review Sheet dated August 22, 1974. S. E. Medall & Associates, Inc. 1 1 Weatherfield Homes 1 1 Sample Depth 1 0 - 25 1 25 - 50 1 1 1 1 1 1 1 1 1 S. E. Medall & Associates, Inc. September 15, 1976 W. 0. 605 ENERGY FOR VARIOUS DEPTHS Drive Energy 1350 foot-pounds 650 foot-pounds PLATE A S. E Medall & Associates, Inc. BORING LOG Project Weatherfield Homes 1 Boring No. 1 Location Diamond Bar WO- 605 Drill Date 8 18 76 Surface Elev. 990 Logged by DRE & BLT Driving Weight W a 3 W WW Z a W c J i a oQ UNIT (soil, fill, alluvium, siltstone, etc.) MATERIAL DESCRIPTION (%sand, silt, clay; caBr, consolidation etc.) ATTITUDE MEASUREMENTS: B-Bedding _F-Fault J-Joint RS-Rupture Surface Contact J m H o_ H~ Qy W o J am C-CORE 8- BAG H w 0 Y ccC- p m ri Nr3zE 0 TOPSOIL - clayey sand, black to dark brown, porous, hard. SC B PUENTE FORMATION - interbedded siltstone 40%, shale 40%, and sandstone 20%, well bedded, laminations 1/16" to 1/2", oc- casional clay seams on laminations, slightly fractured, occasional 1' to 1-1/2' sandstone beds. Well indurated- and moderately cemented. B @ 3' N74W', 12NE B @ 5' N60E, 9NW B @ 7' EW, 15N B @ 9' N80W, 18NE B @ 14' N76W, 16NE-- B @ 17' N70W, 12NE B @ 21' N85E, 12NW B @ 27' N65E, 14NW B @ 32' N85W, 13NE — B @ 44' EW, 16NE 19-1/2''to 21' sandstone interbed, moder- ately cemented. 25' to 26' sandstone interbed, moder- ately cemented. 33 19 15 100 C C C C 102.1 109.1 105.2 99.2 16. 15. 18. 18. 5 10 15 20 25 30 Sheet I of 2 A-1 Proieet Weatherfield Homes Boring No. 1 Location Surface Elev. 990 1. 1 1 1 1 t 1 1 S. IE Medall & Associates, Inc. BORING LOG Logged by DRE & &LT W,O Fn5 Drill Date 8 18 76 Driving Weight F 3 W xf n', C o a Q 0 UNIT (soil, fill, alluvium, siltstone, etc.) MATERIAL DESCRIPTION (%sand, silt, clay; Cobr, consolidation, etc.) ATTITUDE MEASUREMENTS: B-Bedding .._ .. F-Foust J- Joint RS-Rupfure Surface C- Contort H6 M o T ia jWas C-CORE B•BAG r Uo' r o W° r i arW 20 30 Minor fault @ 35' N15E, 78N offset 6", down on north open fractures 1/4" to 1/2". 75 50 C C 87.0 115.5 19. 13.7 35 40 45 50 End of boring at 50 feet. No water; no caving. Sheet 2 of 2 A-1 S. E Medall & Associates, Inc. BORING LOG Weatherfield HomesProject ' Boring No. 2 Location Diamond Bar WA' 6Q5 Drill Date 8 18 76 Surface Elev. 920 Logged by nur• ,c RTP Driving Weight MW e A W x W G 0 o a Q u UNIT (soil, fill, alluvium, siltstone, etc.) MATERIAL. DESCRIPTION (%sand, silt, clay; color, consolidation, etc.) ATTITUDE MEASUREMENTS: B-Bedding F-Fault J - Joint RS-Rupture Surface C- Contant S - Shear J m o v Ng N W am CCORE a-8AG Zz Wo` W p W° Z- or 20 TOPSOIL - clayey sand, black, porous, hard. SC LANDSLIDE DEBRIS - shale, siltstone and sandstone. Tight, no open voids, no dis- oriented blocks. predominately intact. 50 20 20 C C C 118.3 111.9 115.8 5.9 13. 12. 5 10 15 20 shear zone highly disoriented, fractured, crushed, open voids 1/4"tol/2". S@21 N57W 16NE PUENTE FORMATION - interbedded shale 80%) and sandstone (20%), well bedded, well indurated, moderately to well ce- mented. B @ 22' N30W, 9NE Concretion at 26 feet. 25 End of boring at 26 feet due to hard rock. No water; no caving. 30 Sheet of n-? S. E Medall & Associates, Inc. BORING LOG Project Weatherfield Homes Boring No. 3 Location Diamond Bar W.O 605 Drill Date 8/21/76 Surface Elev. 1025 Logged by DRE & BLT, Driving Weight W a it W 2 W O u p Q 0 UNIT (soil, fill, alluvium, slitstone, etc.) MATERIAL -DESCRIPTION (%sand, sift, cleyi color,- consolidation etc.) ATTITUDE MEASUREMENTS: B-Bedding - - F-Fault ..... J-Joint RS-Rupture Surface C- Contact J m H N a.= p. u 08wgN W 39 z° am C-CORE B•BAG z O p c p W= i- N W a a 0 TOPSOIL - sandy clay, black, porous PUENTE FORMATION - interbedded shale (25%), and sandstone (75%), well bedded, lamina- tions on shale 1/2" to 1" thick, occa- sional clay seams pn laminations, well indurated, moderately to well cemented. l' to 2' thick well cemented sandstone intervals common. --- 3' to 4', very hard sandstone. 7' to 9' very hard sandstone 17' to 19' very hard sandstone B @ 3' N84W, 12S B @•5' N20W, 12S B @ 9' N40W, 9S B @ 11' N32W, 8S S @ 14' N42E, 80N B @ 22' N40W, 15S B @ 27' N20W, 14S (clay seam 1/2" thic 23' to 25' concretionary siltstone, very hard.. 25' to 29' very hard sandstone 31' to 40' very hard sandstone 60 31 19 60 C C C C 95.0 111.3 102.5 113.4 14. 17. 21.80 6.1 5 10 15 20 25 30 Sheet 1 of 2 A-3 S. E Medal[ & Associates, Inc. BORING LOG Project Weatherfield Homes Baring No. 3 Location Diamond Bar W.c) 605 Drill Date 8/21/76 Surface Elev 1025 Logged by DRE & BLT Driving Weight w a 3 j w 0 30 OJ u o cp UNIT (soil, fill, alluvium, siltstone, etc.) MATERIAL DESCRIPTION (%sand, silt, clay; ator, cnnsalidation, etc.) ATTITUDE MEASUREMENTS: B-Bedding F-Fault J-Joint RS-Rupture Surface C• Contact End of boring at 40 feet. No water; no caving. N a " Jo w cO w; 2-1 am CCORE B-84G z wa a Y o C i-i vow zo 35 40 Sheet tot 2 A-3 S. E Medall & Associates, Inc. BORING LOG Project Weatherfield Homes Boring No. 4 Location Diamond Bar W.O_ EU-_Drill Date 8 22 76 Surface Elev. 740 Logged by DRE & BT,T Driving Weight 1 Sheet.1 of 2 W Ha 3 Z w c 0 u 2o Q u UNIT (sail, fill, alluvium, siltstone, etc.) MATERIAL DESCRIPTION (%sand, silt, clay; color, consolidation, etc.) ATTITUDE MEASUREMENTS: B-Bedding F-Fault J - Joint RS-Rupture Surface C- Contact m a,"' G o yg. 3WozJ im C-CORE B'gQG uUjG] c wo rz 0 ao TOPSOIL - silty clay, dark brown, porous, hard. CL LANDSLIDE, DEBRIS' -;shale, siltstone and sandstone, inclusions of soil at 7 feet, disoriented blocks of siltstone and sand- stone common. -- Random slickensides at 15 feet. Very soft and punkie at 18 feet. RS @ 26 feet plastic clay with numerous slickensides, 6" thick, dip at 65 degrees. 5 10 15 20 25 30 A-4 Inc. BORING LOG Project Weatherfield Homes Boring No. 4 Location Diamond Bar W.Q.' 605 Drill Date 8 22 76 Surface Elev. 740 Logged by DRE s RLT Driving Weight Sheet 2 of 2 ccW e 3 W Z n', O u o Q 0 UNIT (soil, fill, alluvium, siltstone, etc.) MATERIAL DESCRIPTION (%Sand, silt, clay; color, consolidation etc.) ATTITUDE MEASUREMENTS: B-Bedding F-Fault J-Joint RS-Rupture Surface C- Contort J m v) D o u N~ N W0 am C-CCAE B-BAG 0 G Cr o W= Mz N W o. 2Z 30 1 RS @ 42 N75E, 60S 35 40 45 shear zone highly disturbed, 46-1/2 to 47 clay highly plastic, slickensides RS N65E 26N PUENTE FORMATION - interbedded siltstone 50%), and sandstone (50%),. well bedded, clay seams common, laminations.1/4" to 1/2", well indurated, moderately cemegted, slightly fractured B @ 50 N25W, 25N. 50 55 End of boring at 55 feet. No water; no caving. A-4 S. E Medall & Associates, Inc. LOG OF EXPLORATORY TRENCH i Trench No, 1 Work Order 605 Date 9/3/76 Job Description Landslide Investigation Surface Elev. Drilling Co. Kay's Backhoe Rig & Diameter Used 24" bucket Trench Location Logged By RS Bearing Length 20.0' Depth 8.0' a Depth, Ft. Description and Remarks class color, moisture tightnessetc. 3eologic Structure From To Strike & Di 0 1.5 TOPSOIL: SILTY CLAY - dark brown dry -damp, loose and orous to stiff with roots 1. 5 8 1 SLIDE DEBRIS: PUENTE FORMATION - interbedded jointed @ 5' N60'W 25oNE siltstone shale 75% and fine sandstone brown to @ 6' N65?W 230NE tan to graV and olive green @ 7' N750W 20ONE @ 6.0' 2" olive green clay layer, gouge material very softplastic, 1/2" voids between siltstone and shale beds above and below. S. E. Medall & Associates, Inc. LOG OF EXPLORATORY TRENCH Trench No. 2 Work Order 605 Date 9/3/76 Job Description T,andalidP Tnvecti2ation Surface Elev. Drilling Co. Kav's Backhoe Rig & Diameter Used 24" bucket Trench Location Logged By RS Bearing_ Length 15.0' Depth 5.0' Depth, Ft. Description and Remarks class color, moisture tightness, etc. ologic Structure From To Strike & Di 0 3.0 TOPSOIL: brown siltv clay (CL) dry -damp, stiff, desiccation cracks on the surface. 2-1/2 - 1" wide and 1-1.5' deep 3 5.0 BEDROCK: tan to buff shale, with iron oxide stains, @ 4' N400W, 50NE ti ht hard S. E. Medall & Associates, Inc. LOG OF EXPLORATORY TRENCH Trench No. 3 Work Order 605 Date 9/3/76 Job Description Landslide Investigation Surface Elev. Drilling Co. Kay s Backhoe Rig & Diameter Used bucket Trench Location Logged By RS Bearing Length 20.0' Depth 8.0' Depth, Ft. Description and Remarks class color, moisture tightness, etc. 7eologic Structure From To Strike & Di 0 6.0 TOPSOIL: dark brown silty clay, damp, stiff with caliche streaks @ 5.0' and below 6.0 8.0 1 Light brown clayey silt (75%) with fine sand (25%) and caliche streaks, damp, stiff to very stiff A S. E. Medall & Associates, Inc. LOG OF EXPLORATORY TRENCH Trench No. 4 Work Order 605 Date 9/3/76 Job Description Landslide Investigation Surface Elev. Drilling Co. Kay's Backhoe Rig & Diameter Used 24" bucket Trench Location Logged By RS Bearing I Length 30.0' Depth 6-10.0' Depth, Ft. Description and Remarks class color, moisture tightness, etc. olo is Structure From To Strike & Di 0 9.0 ALLUVIUM: SILTY CLAY - CL - dark brown dr -dam stiff to very stiff, desiccation cracks to 2.0'. Tree roots to 3.0' caliche laver @ 3.0' and below l S. E Medall & Associates, Inc. LOG OF EXPLORATORY TRENCH I Trench No. 4 A Work Order 605 Date 9/3/76 Job Description Landslide Investigation Surface Elev. Drilling Co. Kay's Backhoe Rig & Diameter Used 24" bucket Trench Location Logged By RS Bearing N800E Length 30.0' Depth 10.0' Depth, Ft. Description and Remarks class color, moisture tightness, etc.) ologic Structure From To Strike & Di 0 3.5 SOIL: CLAYEY SILT - (ML) - brown, dry, loose, abundant , tree roots to 4.0' 3.5 10.01 SLIDE DEBRIS: well interbedded, jointed brown to N620W 100 tE purplish gray siltstone, sandstone and shale. @ 5.0'(B) N650W, 150N East end) 0 0 "11 S. E Medall & Associates, Inc. LOG OF EXPLORATORY TRENCH 1 Trench No. 5 ' Work Order 605 Date 9/3/76 Job Description Landslide Investigation Surface Elev. Drilling Co. Kay's Backhoe Rig & Diameter Used 2 bucket Trench Location Logged By RS Bearing N750W Length 40.0' Depth 11.0' Depth, Ft. Description and Remarks class color, moisture tightness, etc. ologic Structure From To Strike & Di 4.0 SOIL: SILTY CLAY - dark brown dry. loose to medium stiff, roots to 4.5' 4.0 11.0 1 SLIDE DEBRIS: well interbeddedjointed, brown to purplish gray sandstone brown siltstone and shale @ 5.0' and below - disturbed and disoriented blocks @ 6.0' N-S, 45oE of sandstone and siltstone 1/4" to 1/2" gaps between @ 8.0' N300W, 35ONE joints and blocks of sandstone and siltstone. @ 9.0' N50E, 100NE S. Ir Medall & Associates, Inc. LOG OF EXPLORATORY TRENCH Trench No. 6 Work Order 605 Date 9/7/76 Job Description landslide Investigation Surface Elev. Drilling Co.3`s u i o Rig & Diameter Used 24" bucket Trench Location Logged By RS Bearing N800E Length 25.0' Depth 9.0' i De th Ft, Description and Remarks class color, moisture tightness, etc. olo is Structure From To Strike & Di SOIL: SILTY CLAY - brown very loose 2 9.0 SLIDE DEBRIS: PUENTE FORMATION - interbedded @ 2.0' N50W 350SW ointed siltstone sandstone and shale• brown buff and @ 4.0' N-S 500W ur lish ra to ra @ 6.0' N150E 450W 7.0' broken and disturbed sandstone and siltstone @ 7.0' N120W 650N 1 4" Raps, very soft zone 1.0' wide clay seam with slicks on siltstone blocks. S. E Medall & Associates, Inc. LOG OF EXPLORATORY TRENCH Trench No. 7 Date 9/7/76WorkOrder605 Job Description Lands Ilide nvestigation Surface Elev. Drilling Co.Kay's Backhoe Rig & Diameter Used 24" bucket Trench Location Logged By RS Bearing N750W Length 20.0' Depth 11.0' Depth, Ft. Description and Remarks class color, moisture tightness, etc. 3eologic Structure From To Strike & Di LLUVIUM: SILTY CLAY TOPSOIL - stiff, dark brown, moist with caliche stringers. 7.0 11.0 Landslide debris interbedded siltstone, sandstone and shales broken up and disoriented color purplish gray to brown sandstone, buff to brown siltstone and dark gray to reddish brown shales; 1/2" wide gaps between some shale blocks, abundant olive green clay coating on rA 7 ny K o 0MV surfaces of siltstones 0' N50E 450SE 0' N100E 350SE S. E Medall & Associates, Inc. LOG OF EXPLORATORY TRENCH Trench No, 8 Work Order 605 Date 9/7/76 Job Description Landslide Investigation Surface Elev. Drilling Co. Kay's Backhoe Rig & Diameter Used 24" bucket Trench Location Logged By RS Bearing N350E Length 20.0' Depth 8.0' Depth, Ft. Description and Remarks class color, moisture tightness, etc. ologic Structure From To Strike & Di 0 3.0 COLLUVIUM: SILTY CLAY - dark brown dry-damp,stiff. 3.0 6.0 COLLUVIUM: Silty clay with abundant caliche streaks and occasional rounded yellowish sandstone block 6.0 8.0 SILTY CLAY - tan to buff, with caliche abundant in - holes rootlet holes Tree roots 3.0' smaller roots to TD. S. E Medall & Associates, Inc. LOG OF EXPLORATORY TRENCH Trench No. 9 ' Work Order 605 Date 9/7/76 Job Description Landslide Investigation Surface Elev. Drilling Co. Kay's Backhoe Rig & Diameter Used 24" bucket Trench Location Logged By RS 1 {I Bearing N400E Length 30.0' Depth 13.0' Depth, Ft. Description and Remarks class color, moisture tightness, etc. 3eologic Structure From To Strike & Di 0 2.5 TOPSOIL: dark brown to silty clay 2.5 ]7.0 SLIDE DEBRIS: weathered bedrock with abundant clay coatings or fragments of siltstone and sandstone. Color mostly brown to light olive brown, abundant accumulation of caliche and clay many roots to 1/2" diameter. 7.0 13.0 Bedrock interbedded siltstone and sandstone, light brown to purplish gray sandstone to olive green to @ 8.0'. N400W, 300NE brown siltstone. Caliche streaks throughout with 0 @ 13+0' N25 W, 350NE abundant clay material 20%, 40% siltstone and 40% sandstone. S. E. Medall & Associates, Inc. LOG OF EXPLORATORY TRENCH Trench No. 10 ' Work Order 605 Date 9/7/76 Job Description Landslide Investigation Surface Elev. Drilling Co. Kay's Backhoe Rig & Diameter Used 24 bucket Trench Location Logged By RS Bearing N650E ngth 35.0' Depth 10.0' Depth, Ft. Description and Remarks class color, moisture tightness, etc. ologic Structure From To Strike & Dip 0 3.0 COLLUVIUM: silty clay, dark brown stiff, dry to damp. Tree roots to 3.0', top 2.0' expansion cracks 3 10.0 Sandy to silty clay - dark brown to light brown, stiff, damp, some slickenside (random) Pods of sandstone (1" x 1" x 111) S. E Medall & Associates, Inc. LOG OF EXPLORATORY TRENCH Trench No. 11 Work Order 605 Date 9/7/76 lob Description T.andc1ir9e Tnvacrigarion Surface Elev. Drilling Co. Kay's Rackhoe Rig & Diameter Used 24" bucker Irench Location Logged By RS Bearing N550E Length 20.0' Depth 12.0' Depth, Ft. Description and Remarks class color, moisture tightness, etc. olo is Structure From To. Strike & Di 0 3.0 TOPSOIL: SILTY CLAY - dark brown dry to damp, stiff Porous with expansion cracks 3.0 5.0 1 SANDY CLAY - dark brown dry to dame stiff 5.0 11.0 SLIDE DEBRIS: clay with inclusions of topsoil (silt cla br--- very moist stiff, very slick and plastic also includes ods of reddish brown to yellowish brown sandstone 2' to 3' diameter @10.0' N750E 55oNW 1.0 12.0 Broken and ddsoriented fragments of reddish to yellow- ish brown siltstone and sandstone, abundant clay and small rootlets @ 8.0' 4 inch diameter pod of topsoil v porous. S. E. Medall & Associates, lnc Date SEFT. / J /974i Job NEn THEE: Fll' L D kc;'V' E U. Cn Y SHEAR TEST DIAGRAM 3.5 3.0 2.5 2.0 1.5 0 m 1.0 0.5 n W.O. 005 0 . 0.5 1.0 1.5 2.0 2.5 Normal Pressure K S F 8-3 @ 20- 21 FT. Key: REMOLDcD AND SATURATEO O Tests of field moisture content. 0 Tests at saturated molsture content. 3.0 Q = 26° c = 0.75 kSF PLATE C-/ CRITICAL HEIGHT AREA OF ELEMENT , A - .4dx WF/ CHT , W - yA SL/. 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V r-1 4 OQ M M U E Z d" 0 Q O 00ra mM 0\ w JQ W a m r o 2 Q y00 NN r01 rrn1 LL Lc 4 m O Z J • fUf O O O OWZ N M Z N O W« a a M m N0 0.- coI v Nr W iL N U) m. 10 J 1~i co a m m r C 8(Gn N d' O VN N M o am 00 c r, m o r m u z o rn rn Y rr-I 4 I N m m O O O Z m O ONH 01 W O J o ri ra z Q F-' m o m 7 ( N N Ul N V W U- SQ ITo mrn r Uj ra r rn W O N J U oZ 1 1 Fa- O N i m 0 U Ell CD U mC U ui 0 LN ri rN' r rm 7 N o n Ln rrU) o U) W ON W- moko W r1 v) N 1 ri r O Ra M w or In r+ 06CXa JF' moo a U ri CDri r V N r N a a It O fn IL 2+v d N L FGFND A Af ARTIFICIAL FILL 6VATERNARY ALLUVIUM O/s QUATERNARY LANDSLIDE DEBRIS Tmp PUENTE FORMATION CONTACT PLUNGING ANTICLINE ATTITUDE OF BEDDING 5 ATTITUDE OF FAULT PLANE TEST O PIT- _ TEST PIT- MEDALL LOCKWOOD- SINGH BORING - MEDALL BORING - LOCKWOOD - SINGH BORING - LAWMASTER CROSS SECTION W,0. 605 I e ,j 0 0 1 A Z U N v N S + O C C r-i if1 LLpL I I ri N w B Z N o a v r r Qp" U- M 00 o ro c J U' ri N N N in D NZo i J a Uf O Ifl D1 O to K.. 2 U- NI r I rri r N U W ; rl Ln d' M Ch oN p F r m O rn co W Nto 07 N D N to N J W M N M N C comlyV6. V' In 01 C ri Y3 N Ln lD 00 c!1 m D 00 N w 01 O n co rn co N U co rn rn rn Ln W m o n cr U. cng rn w o 3 I I N co to N W O V' M n O O Z 00 n o m r00 I I 0 0 J 0 CDZ m o n I 00 N e--I r-I Ul Q I I f" CON tD lD d' vl 7 d r tD rn ON m YJ N In lD In Ln W 1i M o000000 v vo Q r N ITIn OLn In WU p in tD JQ N M Q F- r w y co GG eh W lyJ W O tD 1 In Nn C mcr 7:to, 4 n MD Ln f r i cn G A0 ri W W OD1 0 O W W U p Cl) N g U) STANDARD GRADING SPECIFICATIONS These specifications present the usual and minimum requirements for grading operations performed by S. E. Medall f, Associates, Inc. No deviation from these specifications will be allowed, except where specifically superseded in the preliminary geology and soils report, or in other written communication signed by the Soils Engineer or Engineering Geologist. I GENERAL A. The Soils Engineer and Engineering Geologist are retained to observe compaction of fills and excavation of slopes on the project. For the purpose of these specifications, observation by the Soils Engineer includes that inspection performed by any person or persons employed by, and respon- sible to, the licensed Civil Engineer signing the soil report. B. All clearing, site preparation or earthwork performed on the project shall be conducted by the Contractor under the observation of the Soils Engineer. C. It is the Contractor's responsibility to prepare the ground surface to receive the fills to the satisfaction of the Soils Engineer and to place, spread, mix, water and compact fill in accordance with the specifications of the Soils Engineer. The Contractor shall also remove all material considered unsatisfactory by the Soils Engineer. D. It is also the Contractor's responsibility to have suit- able and sufficient compaction equipment on the jobsite to handle the amount of fill being placed. If necessary, excavation equipment will be shut down to permit comple- tion of compaction. Sufficient watering apparatus will also be provided by the Contractor, with due considera- tion for the fill material, rate of placement and time of year. E. A final report shall be issued by the Soils Engineer and Engineering Geologist discussing the conformance with these specifications. II SITE PREPARATION A. All vegetation and deleterious material such as rubbish shall be disposed of offsite. This removal must be con- cluded prior to placing fill. S. E. Medall & Associates, Inc. Standard Grading Specifications Page.2. B. The Soils Engineer shall locate all houses, sheds, sewage disposal systems, large trees or structures on the site or on the grading plan to the best of his knowledge prior to preparing the ground surface. C. Soil, alluvium or rock materials determined by the Soils Engineer as being unsuitable for placement in compacted fills shall be removed and wasted from the site. Any material incorporated as a part of a compacted fill must be approved by the Soils Engineer. D. After the ground surface to receive fill has been cleared, it shall be scarified, disced or bladed by the Contractor until it is uniform and free from ruts, hollows, hummocks or other uneven features which may prevent uniform compaction. The scarified ground surface shall then be brought to optimum moisture, mixed as required, and compacted as specified. If the scarified zone is greater than twelve inches in depth, the excess shall be removed and placed inlifts restricted to six inches. Prior to placing fill, the ground surface to receive fill shall be inspected, tested and approved by the Soils Engineer. E. Any underground structures such as cesspools, cisterns, mining shafts, tunnels, septic tanks, wells, pipe lines or others not located prior to grading are to be removed or treated in a manner prescribed by the Soils Engineer. 1. III COMPACTED FILLS A. Any material imported or excavated on the property may be utilized in the fill, provided each material has been determined to be suitable,by the Soils Engineer. Roots, tree branches and other matter missed during clearing shall be removed from the fill as directed by the Soils Engineer. B. Rock fragments less than six inches in diameter may be utilized in the fill, provided. 1. They are not placed in concentrated pockets. 2. There is a sufficient percentage of fine-grained material to surround the rocks. 3. The distribution of the rocks is supervised by the Soils Engineer. S. E. Medall & Associates, Inc. Standard Grading Specifications Page 3 C. Rocks greater than six inches in diameter shall be taken offsite, or placed in accordance with the recom- mendations of the Soils Engineer in areas designated as suitable for rock disposal. Details for rock disposal such as location, moisture control, percentage of rock placed, etc., will be referred to in the "Conclusions and Recommendations" section of the soils report. If rocks greater than six inches in diameter were not anticipated in the preliminary soils and geology report, rock disposal recommendations may not have been made in the "Conclusions and Recommendations" section., In this case, the Contractor shall notify the Soils Engineer if rocks greater than six inches in diameter are encoun- tered. The Soils Engineer will than prepare a rock disposal recommendation or request that such rocks be taken offsite. D. Material that is spongy, subject to decay, or otherwise considered unsuitable shall not be used in the compacted fill. E. Representative samples of materials to be utilized as compacted fill shall be analyzed in the laboratory by the Soils Engineer to determine their physical properties. If any material other than that previously tested is encountered during grading, the appropriate analysis of this material shall be conducted by the Soils Engineer as soon as possible. F. Material used in the compacting process shall be evenly spread, watered, processed and compacted in thin lifts not to exceed six inches in thickness to obtain a uni- formly dense layer. The fill shall be placed and com- pacted on a horizontal plane, unless otherwise approved by the Soils Engineer. G. If the moisture content or relative density varies from that required by the Soils Engineer, the Contractor shall rework the fill until it is approved by the Soils Engineer. H. Each layer shall be compacted to 90 percent of the maximum density in compliance with the testing method specified by the controlling governmental agency. In general, ASTM D-1557-70T will be used, either with a 5-layer or 3-layer curve.) If compaction to a lesser percentage is authorized by the controlling governmental agency because of a specific land use or expansive soil conditions, the area to receive fill compacted to less than 90 percent shall either be delineated on the grading plan or appropriate reference made to the area in the soil report. S. E. Medall & Associates, Inc. Standard Grading Specifications Page 4 I. All fills shall be keyed and benched through all top- soil, colluvium, alluvium or creep material, into sound bedrock or firm material where the slope receiving fill exceeds a ratio of five horizontal to one vertical, in accordance with the recommendations of the Soils Engineer. J. The key for side hill fills shall be a minimum of 15 feet within bedrock or firm materials, unless otherwise specified in the soils report. (See detail on Plate GS-1) K. Drainage terraces and subdrainage devices shall be constructed in compliance with the ordinances of the controlling governmental agency, or with the recommenda- tions of the Soils Engineer and Engineering Geologist. L. The Contractor will be required to obtain a minimum relative compaction of 90 percent out to the finish slope face of fill slopes, buttresses and stabilization fills. This may be achieved by either overbuilding the slope and cutting back to the compacted core, or by direct compaction of the slope face with suitable equip- ment, or by any other procedure which produces the required compaction. The Contractor shall prepare a written detailed descrip- tion of the method or methods he will employ to obtain the required slope compaction. Such documents shall be submitted to the Soils Engineer for review and comments prior to the start of grading. If a method other than overbuilding and cutting back to the compacted core is to be employed, slope tests will be made by the Soils Engineer during construction of the slopes to determine if the required compaction is being achieved. Each day the Contractor will receive a copy of the Soil Engineer's "Daily Field Engineering Report" which will indicate the results of field density tests for that day. Where failing tests occur or other field problems arise, the Contractor will be notified of such conditions by written communication from the Soils Engineer in the form of a conference memorandum, to avoid any misunderstanding arising from oral communication. If the method of achieving the required slope compaction selected by the Contractor fails to produce the neces- sary results, the Contractor shall rework or rebuild such slopes until the required degree of compaction is obtained, at no additional cost to the Owner or Soils Engineer. Standard Grading Specifications Page 5 M. 'All fill slopes should be planted or protected from erosion by methods specified in the soils report. N. Fill -over -cut slopes shall be properly keyed through topsoil, colluvium or creep material into rock or firm materials; and the transition shall be stripped of all soil prior to placing fill. (See detail Plate GS-Z) 1 IV CUT SLOPES A. The Engineering Geologist shall inspect all cut slopes excavated in rock, lithified or formation material at vertical intervals not exceeding ten feet. B. If any conditions not anticipated in the preliminary report such as perched water, seepage, lenticular or confined strata of a potentially adverse nature, unfavorably inclined bedding, joints or fault planes are encountered during grading, these conditions shall be analyzed by the Engineering Geologist and Soils Engineer; and recommendations shall be made to treat these problems. C. Cut slopes that face in the same direction as the prevailing drainage shall be protected from slope wash by a non -erosive interceptor swale placed at the top of the slope. D. Unless otherwise specified in the soils and geological report, no cut slopes shall be excavated higher or steeper than that allowed by the ordinances of con- trolling governmental agencies. E. Drainage terraces shall be constructed in compliance with the ordinances of controlling governmental agencies, or with the recommendations of the Soils Engineer or Engineering Geologist. V GRADING CONTROL A. Inspection of the fill placement shall be provided by the Soils Engineer during the progress of grading. S. In general, density tests should be made at intervals not exceeding two feet of fill height of every 500 cubic yards of fill placed. This criteria will vary depending on soil conditions and the size of the job. In any event, an adequate number of field density tests shall be made to verify that the required compaction is being achieved. S. E. Medall & Associates, Inc. Standard Grading Specifications Page 6 C. Density tests should also be made on the surface mate- rial to receive fill as required by.the Soils Engineer. ._ D. All cleanout, processed ground to receive fill, key excavations, subdrains and rock disposal must be inspected and approved by the Soils Engineer prior to placing any fill. It shall be the Contractor's responsibility to notify the Soils Engineer when such areas are ready for inspection. VI CONSTRUCTION CONSIDERATIONS A. Erosion control measures, ;vhen necessary, shall be provided by the Contractor during grading and prior to the completion and construction of permanent drainage controls. B. Upon completion of grading and termination of observa- tions by the Soils Engineer, no further filling or excavating, including that necessary for footings, foundations, large tree wells, retaining walls, or other features shall be performed without the approval or the Soils Engineer or Engineering Geologist. C. Care shall be taken by the Contractor during final grading to preserve any berms, drainage terraces, interceptor swales, or other devices of a permanent nature on or adjacent to the property. S. E. Medall & Associates, Inc. TYPICAL FILL OVER NATURAL SLOPE TOE SHOWN ON , GRADING PLAN PROJECTED / 4' Typical I l/2'1 Of NATURAL SLOPE / a 10' Typical BEDROCK OR FIRM FORMATION MATERIAL Minimum 15' Minimum NOTE , WHERE NATURAL SLOPE GRADIENT LESS BENCHING IS NOT NECESSARY, STRIPPING DID NOT REMOVE ALL MATERIAL. IS 5:1 OR UNLESS COMPRESSIBLE S. E. Medall & Associates, Inc. DATI !T . lCAtl WO. PLATE G S -I W d O V) D U Cr W O 1 J_ tL J Q U_ a H Z O H a. WzJWd O Na 0 F-z0 Jd IL Q J7 W > O J tit EJF- QulO i`I S. E. M©dall & Associates, Inc. IIA11 Or fCAll WO. PLATE G S - 2