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HomeMy WebLinkAboutVILLAS ON MAIN - FDP240006 - SUBMITTAL DOCUMENTS - ROUND 1 - Geotechnical (Soils) ReportGEOTECHNICAL EXPLORATION F'OR PARCEL NUMBER 97 OI4OOO32, ALTA VISTA SUBDIVISION, CITY OF FORT COLLINS, LARIMER COUNTY, COLORADO F'OR BOB LONG CDS ENGINEERING CORPORATION LOVELAND, COLORADO PROJECT NUMBER 23-2206 DECEMBER 18,2023 December 18,2023 Project No.23-2206 Bob Long P.O. Box 1936 Fort Collins, CO 80522 Dear Bob, Enclosed is the report you requested ofthe geotechnical exploration for the proposed residences to be located on Parcel Number 9701400032, AltaVista Subdivision, City of Fort Collins, Larimer County, Colorado. The site appears to be suitable for the construction of the proposed residences, provided the design criteria and recommendations given in this report are followed. If you have any further questions concerning the information in this report, please contact this office. Respectfully, FOR AND ON BEHALF OF CDS ENGINEERING CORPORATION Marin Shaffe neering Technician 165 2nd Street S.W. . Loveland, CO 80537 .(970) 667-8010 . Fax (970) 667-8024. www.cds-eng.net Kevin F. Becker, Enclosures TABLE OF CONTENTS Letter of Transmittal Table of Contents Scope Site Investigation Site Location and Description Subsurface Conditions Foundation Recommendations Later al Earth Pre s sure s Slab Construction Foundation Drain System Conclusions ATTACHMENTS Location of Test Borings Symbols and Soil Properties Log of Borings Swell-Consolidation Test Results Summary of Test Results Post-Construction Site Preparation and Maintenance Typical Perimeter Drain Details Placement of Compacted Fill Materials Page i ii 1 1 2 2 J 4 5 6 6 Figure No. I Figure No. 2 Figure No. 3 FigureNos.4&5 Table No. I Appendix 1 Appendix 2 Appendix 3 1 SCOPE This report presents the results ofour geotechnical exploration for the proposed residential buildings to be located at the project site. The buildings are anticipated to be of typical wood frame construction. Crawlspace construction is anticipated for these structures. This exploration was conducted to provide recommendations pertaining to the type and depth of foundation system, allowable soil bearing pressures, groundwater conditions, and to identify any complications that may be encountered during or after construction due to subsurface conditions. This report has been prepared for the exclusive use of our client for the project discussed. If the building location or the scope of the project should change, CDS Engineering shall be notified prior to construction to review the report and provide alternate recommendations if deemed necessary. Additional borings may be required to provide the alternate recommendations. Additional fees may apply. SITE INVESTIGATION The field investigation performed on November 27 and November 30, 2023, consisted of drilling, logging, and sampling three (3) test borings across the site. The borings ranged in depth from twelve (12) to twenty (20) feet. The location of the Test Holes is shown on Figure No. l. Boring locations were established by a representative of CDS Engineering Corporation based on a site plan provided by the client. Graphical logs of the borings are shown on Figure No. 3. The descriptions of the soils and/or bedrock strata are based, primarily, on visual and tactual methods which are subject to interpretation. The test borings were advanced using a truck mounted, four (4) inch diameter, continuous flight auger drill rig. Laboratory samples were obtained by driving a two and one-half (2%) inch diameter California-type, split barrel sampler twelve (12) inches (or as shown) into undisturbed soils with a 140-pound hammer falling thirty (30) inches. Bag samples of auger cuttings may have also been collected. 2 Laboratory tests performed were - Swell-Consolidation, Natural Moisture, Natural Dry Densities, and Grain Size Analysis. All tests were conducted in accordance with ASTM standards. A Summary of the Swell-Consolidation Test Results is shown on Figure Nos. 4 and 5. A Summary of Test Results is shown on Table No. 1. SITE LOCATION AND DESCzuPTION The site is located in east Fort Collins, south of Suniga Road, west of Lindenmeier Road, and on the north side of Main Street, Larimer County, Colorado. The site is in a developed urban subdivision with paved roads and utilities, and vegetation consists primarily of weeds. The site is relatively flat. SUBSURFACE CONDITIONS Based on the borings drilled within the proposed building footprint, the subsurface conditions at the site consist of clay underlain by gravel/cobbles. Groundwater levels were recorded after completion of the drilling operations. During our field exploration groundwater was encountered in the test borings at depths ranging from seven (7) to eight (8) feet. The water levels listed above are the stabilized levels of the free groundwater surface at the time of this exploration and may not properly define yearly groundwater levels. The groundwater table should be expected to fluctuate throughout the year depending on seasonal moisture variations. Refer to the Log of Borings, Figure No. 3, for additional details specific to each boring. Although evidence of underground facilities such as, but not limited to, septic tanks/fields, cesspools, cistems, foundations, utilities or mining operations were not observed during our exploration, such features could be encountered during construction. If unexpected fill or underground facilities are encountered, proper remediation should be taken. Alternate recommendations, other than those provided in this report, may be required. 3 FOUNDATION RECOMMENDATIONS The type of foundation best suited for a particular building site is dependent not only on the characteristics of the soil and rock but also depends on the type of structure, depth to groundwater, the proposed depth of excavation, and owner preference. The recommendations that follow are primarily based on the type of soil or bedrock encountered. Based on the conditions observed in the field and laboratory tests, we recommend the foundations be a continuous spread footing and isolated pad foundation. Due to the swell potential of the upper clays at this site, we recommend that all footings be placed a minimum of four (4) feet below grades which existed at the time of our exploration. Or the footings could be supported by a three (3) foot thick structural soil mat. Continuous Spread Footing and Isolated pad Foundation The foundation should be a continuous spread footing and isolated pad foundation designed for a maximum allowable bearing capacity of 1,500 pounds per square foot (dead load plus full live load) and a minimum dead load of 500 pounds per square foot to help counteract the swelling should the subsoils become wetted. The bottom of the footings should be kept a minimum of two (2) feet above the groundwater. The foundation is to bear on the native, undisturbed clays or on a structural soil mat, and not on unapproved fill, topsoil, or frozen ground. The bottom of all foundation components should be kept at least thirty (30) inches (or per local code) below finished grade for frost protection. The open excavation should not be left open for an extended period of time or exposed to adverse weather conditions. Excessive wetting or drying of the excavation should be avoided during construction. Excavations that are inundated with water may soften and require re-compaction, or removal, of the exposed subgrade soils. The completed open excavation should be observed by a representative of CDS Engineering Corporation in order to verifr the subsurface conditions from test-hole data. The compacted soil mat should be comprised of moisture and density controlled, imported materials approved by the engineer prior to delivery or placement. The mat should be at least three (3) feet thick and should extend, at a minimum, the thickness of the soil replacement, beyond the outside edge of the footings. The compacted soil mat could also be constructed 4 under floor slab areas to reduce the amount of potential slab movement. Potential movement can be reduced but will not be completely eliminated. The deeper the soil replacement is conducted, the less risk of movement there will be. The soils that are to be used for the compacted soil mat shall be adequately broken, crushed and the moisture well blended prior to placement. The soils should be placed and compacted, with compacted lifts not exceeding six (6) inches, to the moisture and density specifications described in Appendix 3 of this report. Each twelve (12) inches of the compacted soils should be tested and approved prior to placing the next lifl. The Geotechnical Engineer shall be retained to supervise the placement of fiIl material. It is the contractor's responsibility to contact the engineer a minimum of 24 hours in advance to schedule the testing. The fill shall be evaluated after placement is complete to verify the bearing values assigned above. Allow three to five business days for additional testing prior to placement of concrete. LATERAL EARTH PRESSURES Lateral earth pressures are forces exerted on earth retaining structures and foundation components, by the soil. The pressure exerted is influenced by wetting of the backfill soils, type and compaction of the backfill and the methods used to compact the backfill. For the soils, above the free groundwater surface at this site, we recommend the foundation components be designed using the following equivalent fluid pressures. o Active Pressure :45 pcf o At Rest Pressure : 65 pcf These values assume that the positive drainage will be maintained throughout the life of the structure. It is our opinion that the on-site soils encountered could be used as backfill material against fbundation walls. The soils shall be moisture conditioned and well pulverized so that all fragments are smaller than six (6) inches. Refer to Appendix I lbr additional backfill information. If there is opportunity for the backfill soils to become saturated, we shall be notified to revise the minimum equivalent fluid density. These values do not include a factor of safety or take into account any surcharge loading. 5 SLAB CONSTRUCTION Although crawl space construction is anticipated for this structure, the following may benefit garage slabs and exterior flatwork. Changes in the moisture contents may result in consolidation or swelling of the subsoil, resulting in differential slab movement. The soils encountered and tested at this site exhibit no to high swell potential as moisture contents are increased. According to the Guideline for Slab Pedormance Risk Evaluation and Residential Basement Floor System Recommendations, developed by the Colorado Association of Geotechnical Engineers, slab performance risk at this site would be considered low to moderate. Slabs placed on the native, unaltered soils or bedrock at this site may experience excessive heaving and cracking. We recommend that structural floors be constructed at this site, in place of slabs-on- grade, where these areas may or are to be finished. Areas with slabs placed on the native clays at this site shall be considered non-habitable, and therefore should not be finished for risk of damage caused by slab movement. An altemative which could reduce the risk of potential slab movement would be to remove at least three (3) feet of soil beneath the slab and replace it with a moisture and density-controlled fill approved by the engineer prior to delivery or placement. This method may reduce the risk of potential slab movement, but it will not completely eliminate potential damage. Refer to Appendix 3 of this report for compaction guidelines. This method may also benefit garage slabs and exterior flatwork. If slabs-on-grade for non-habitable areas are chosen and the owner is willing to accept the risks of potential damage from slab movement, slabs should be constructed to be ,,free-floating', and isolated from all structural members of the foundation, utility lines, and partition walls. There should be a minimum two (2) inch void constructed below partition walls located over slabs-on- grade. The void should be increased to four (4) inches for slabs placed on potentially expansive bedrock stratum. Eliminate under-slab plumbing where feasible. Where such plumbing is unavoidable, it should be pressure tested before and after slab construction to minimize leaks which would result in wetting of the subsoil. Failure to allow the slab to float independently could result in functional, structural, architectural, and utility line damage. All slabs should be scored into maximum 225 squate foot areas or maximum dimensions of fifteen (15) feet with a minimum 6 depth of one (1) inch to localize and control any cracking due to heaving. Any slabs less than thirty (30) square feet should be scored at least once in each direction. The minimum slab thickness should be four (4) inches, with four (4) inches of clean, washed gravel under the slab. Slabs should be reinforced with welded wire fabric, or equivalent, to help control cracking and separation. Fiber mesh shall not be considered an equivalent substitute for the welded wire fabric. Areas to be finished shall utilize a structural floor system or a compacted structural mat as described above. FOLINDATION DRAIN SYSTEM A perimeter drain system shall be installed where below grade habitable spaces are constructed. The drain shall be constructed around the entire exterior perimeter of the foundation of any below grade habitable space. Perimeter drains around crawl space areas, shall be installed as required by the current building code or by local jurisdictions. The drain system should contain a four (4) inch diameter perforated drainpipe surrounded by clean, washed rock. There should be a minimum of six (6) inches of gravel over the top of the pipe, for the full width of the trench. The gravel shall be covered with untreated building paper or geotextile fabric to minimize clogging by backfill material. The drain should havl a positive slope to a non-perforated sump pit or to daylight, well away from the foundation. The sump pit should be a minimum of twenty-four Q$ inches in diameter by two (2) feet deep and should be surrounded by at least six (6) inches of clean gravel similar to that provided around the drain. The sump pit shall be capable of positive gravity or mechanical drainage to remove any accumulated water. The drainage system shall discharge aminimum of five (5) feet beyond the backfill zone. The discharge area should be placed so that it does not interfere with adjacent properties. Typical drain details are provided in Appendix 2 of this report. CONCLUSIONS The soils encountered at this site exhibit no to high swell potential as moisture contents are increased. Owners should be cautioned of the risk of damage caused by the introduction of excess water to the soils and/or rock. Due to the expansive soils andlor bedrock located within the test 1 perimeter for this analysis, and recognizing the high probability of construction phase and/or post construction wetting potentials of these soils, it is recommended that the contractor/owner refrain from installing any in-ground or underground water features at this site. In-ground andlor underground water features may consist of, but are not limited to: swimming pools, hot tubs, ponds, on/under-surface streams, fountains, etc. All new and future owners should be directed to those items under "Post-Construction Site Preparation and Maintenance" in Appendix l, included in this report. Our experience has shown that damage to foundations usually results from saturation of the foundation soils. Homeowners must assume responsibility for maintaining positive drainage around the structure and incorporating appropriate landscaping that will not interf-ere with the positive drainage. It is recommended that a copy or summary of this repoft be provided to any new or future owners of this properly. A copy of A Guide to Swelling Soils./br Coloraclo Homebuyers and Homeot4tners, Colorado Geological Survey Special Publication 4-i should also be provided to any new or future owners of the property. The findings and recommendations of this report have been obtained in accordance with accepted prof'essional engineering practices in the field of Geotechnical Engineering. However, standard Geotechnical Engineering practices and related government regulations are subject to change. The recommendations provided in this report are lbr the exclusive use of our client and are not valid for use by others. If the construction takes place approximately three (3) years beyond the date of this report, we should be contacted to review the information with regard to updated governmental requirements or industry standards. Additional fees may apply. There is no other warranty, either expressed or implied. We do not guarantee the performance of the project in any respect, but only that our engineering work and judgments rendered meet the standard of care of our profession. This report applies only to the type of construction anticipated in the area tested. The current technology is not at a stage where a guarantee of "absolutely no damage', can be assured by design and construction practices. N 69'J3'5i" $i JJl.:8 ,,HDPE P!F: r t0r7 MAIN s- PAnC:L S7Cl419CC -r I --_=__i_-l-41 rli:l 1023 LrA,N SI I ul5 L,NJ:NMLILR RD I IPA{,t I q?flr4tc(1r7 I pAnLrL .17c140c315 I Il,lIti ri ITLVLRSL CRO'IIN " ALICN}'E\' SCALE 1"=50' Location of Test Borings EnoineerinoJ l. Juorporolron 165 2nd St. S.W., Lowlond, Colorodo 80537 Tde (970) 667-8010 ) Date: 12118123 Client Bob Long Project: PN 9701400032, Alta Vista Subdivison, Fort Collins, Larimer County, Colorado Project No. 23-2206 Drawn By: MES Figure: 1 UTILITr' AND ORAlI,] AGI' j-. I I NO, 4 REEAR 86 41 Cu(B A\D t;, rtt iserLr) -./SUBBASE 2,CO\CRETE PAII J r.." ' j .i, . ,.' .'.: .} 4 \\\ Itt I Fiil Gravel N/12 CALIFORNIA Sand sitt Silty Clay Clay Weathered Bedrock Siltstone Claystone Sandstone Limestone lgneous & Metamorphic N/12 SPLIT SPOON THIN WALLED (SHELBY) BAG SAMPLE PITCHER SAMPLE Penetration Resistance and strength crassifications are Based The Standard penetration Test Number of Blows Per foot (N)* Relative Density Cohesionless Soils Consistency Cohesive Soils Approximate Cohesion ksf** 0-4 4_10 10-30 30-50 50+ BLOWS PER FOOT - BLOWS OF 140 LB. HAMMER DROPPED 30 IN. TO DRIVE SPLIT SPOON OR CALIFORNIA SAMPLER 12 lN. (ASTM D1586-67) EQUIVALENT TO PPt2 AND eu/2 Very Loose Loose Medium Dense Very Dense Soft Firm stiff Very Stiff Hard < 0.5 0.5-1.0 1.0-2.0 2.0-4.O > 4.0 165 2nd St. S.W., Lowlond, Colorodo 80537 Tde (970) 667-3010En oin eerin o Coiporotiofi SYMBOLS & SOIL PROPERTIES FIGURE NO.2 ooIM>-Ur --{ m-L @ mr- = O FT- TH-1 (11t21) TH.2 (11l30) TH-3 (11t30) osIm>rls=m-I @ mro€ O FT, 15t12 5FT 5FT 1O FT.1O FT. 15 FT.15 FT 20 FT. 25 Fr.25 FT. 30 FT.30 FT 35 FT. m H H CLAY: tr. calc, tr. roots, brown/dk. brown, sl. moist to v. moist, stiff to v. stiff GRAVEL/COBBLES: sand, brovtin/grey, damp, dense to v. dese CLAYSTONE: weathered, dk. grey Borings drilled 11121123 & 11tZ)t2A using a 4" diameter, continuous flight truck mounted drilling rig. + Groundwater.@dri[ing & Cave on 11130123 Al1 roll. ond/or rock contoctc- !ho*.-* bodng logo orc opproxlmotc ond rcprctcnt lub!rurfocc condluonr of ilmcof drllllng. Borlng loga ond lnformotlon prcaartcri on logi'orc aubFct to aircusalon ond llmltofloni oi trra rbort. Boring Log En oin eerino Coiporotioi 165 2nd St. S.W, Lowlond. Colorodo 80557 Tde: (970) 667-8010 Date: 12118t23 Client: Bob Long Project: PN 9701400032, Alta Vista Subdivison, Fort Collins, Larimer County, Colorado Project No. 23-22Oo Drawn By: MES JFigure: 20 FT 35 FT. SWELL / CONSOLIDATION TEST CURVES Client: Bob Long Project: PN 9701400032 Alta Vista Subd., Fort Collins Project No.:23-2206 Boring: Depth, ft: Swell(%):* TH-I 2', Description: Clay, tr. calc, brown, v. moist, stiff 5.2 Water Content: 22.0% Dry Density, pcft --iI3-Approximate Swell Pressure, psf:9000 Pressure, psf I 000100 U U 6 5 4 3 2 I 0 -l -J -4 -6 \ \ \ Boring: Depth, ft: Swell (7o):* TH-2 4.9 100 Pressure, psf 1000 10000 Description: Clay. tr. calc, brown, sl. moist, v. stiff Water Content: 11.3% Dry Density, pcf: JIZ- Approximate Swell pressure, psf: 10000 6 5 4 3 -) a:b, I 5o o E-r -3 -4 -5 -6 I 00000 * negative values indicate consolidation Figure 4 \ \ CDS Engineering Corporation I {-I I t Client: Project: Bob Long SWELL / CONSOLIDATION TEST CURVES PN 9701400032, Alta Subd., Fort Collins Project No.: 23-2206 Boring: TH-3 Depth, t1----T Swell (%):* 2.2 100 Dry Density, pcf: 105.9 Approximate Swell pressure, psf: 5000 Pressure, psf 1000 10000 * negative values indicate consolidation Figure 5 6 5 4 3 riuoI d 90 = -lE>1 -3 -4 -5 -6 CDS Engineering Corporation $o oo a (ooNc{ I (f)N oz oo.6. L(L oFJfo IIIt FAcit/,lJ ZFq ILJel>Ft E fo l5 l6lplol2lol3 l6 | _(,, IE lsl= ldt> lg l(sIo)l0) l1lorlo l6l<lo llloIrld) o o)o.o o oEc =o)c o =o o5o o =@ APPENDIX 1 Backfill When encountering potentially expansive or consolidating soils, measures should be taken to prevent the soil from being wetted during and after construction. Generally, this can be accomplished by ensuring only minimal settlement of the backfill placed around the foundation walls' It should be understood that some backfill settlement is normal and should be anticipated. Areas that do settle should be repaired immediately to prevent ponding around the foundation. Water may need to be added to backfill material to allow proper compaition -- do not puddle or saturate. Backfill should be mechanically compacted to at least 90Yo of Standard proctor. Compaction requirements could be verified with field tests by the Engineer. It is the contractor,s responsibility to contact the engineer for such tests. Surface Drainage The final grade should have a positive slope away from the foundation walls on all sides. At minimum, the slope shall meet the requirements of the governing Building Code. Where site grading allows, we recommend a minimum of six inches 16;'; in the first five feet (5,). Downspouts and sill cocks should discharge into splash blocks that extend beyond the limits of the Uacml. Splash blocks should slope away from the foundation walls. The usl of long downspout extensionsin lieu of splash blocks is advisable. Surface drainage away from t[. fo*aution shall be maintained throughout the lifetime of the structure. Lawn Irrigation Do not install sprinkler systems next to foundation walls, porches, or patio slabs. If sprinkler systems are installed, the sprinkler heads should be placed so that the spray from the heads underfull pressure does not fall within five feet (5') of foundation walls, por.h.r, or patio slabs. Lawn inigation must be carefully controlled. If the future owners desire to plant next to foundation walls, porches, or patio slabs, and are willing to assume the risk of structural damage, etc., then it is advisable to plant only flowers and shrubber! (no lawn) of varieties that require very little moisture. These flowers and shrubs should be hani watered only. Landscaping with a plastic covering around the foundation area is not recommended. Check with your local landscaper for fabrics which allow evaporation when inhibiting plant growth when a plastic landscape covering is desired. Experience shows that the majority of problems with foundations due to water conditions aregenerally due to the owner's negligence of maintaining proper drainage of water from the foundation area. The future owners should be directed to pertlnent informa-tion in this report. REV 7/30/13 EXTERIOR AND/OR INTERIOR PERIMETER DRAIN FOOT!NG FOUNDATION COMPACTED BACKFILL PER SOIL REPORT UNTREATED BUILDING PAPER OR GEOTEXTILE OVER TOP OF GRAVEL CLEAN WASHED ROCK. MINIMUM OF 6" OVER THE TOP OF THE PIPE 4" PERFORATED PIPE, RIGID OR FLEXIBLE. SLOPE TO SUMP PIT OR DAYLIGHT. FDN WALL, ryP. REINFORCEMENT NOT SHOWN OPTIONAL MOISTURE BARRIER. 6.MIL MINIMUM, ATTACH TO FOUNDATION WALL A MINIMUM OF 6" ABOVE votDs oR GRAVEL (WHTCHEVER tS GREATER). CONTINUE BELOW PIPE AND UP SIDE OF TRENCH AS SHOWN. FLOOR BY OTHERS ADDTIONAL LATERALS AS RECOMMENDED DRAIN TRENCH SHALL NOT CUT INTO 1:1 SLOPE AWAY FROM THE EDGE OF THE FooTING EXTERIOR AND/OR DRILLED INTERIOR PERIMETER DRAIN P!ER FOUNDATION COMPACTED BACKFILL PER SOIL REPORT UNTREATED BUILDING PAPER OR GEOTEXTILE OVER TOP OF GRAVEL CLEAN WASHED ROCK. MINIMUM OF 6'OVER THE TOP OF THE PIPE 4'PERFORATED PIPE, RIGID OR FLEXIBLE. SLOPE TO SUMP PIT OR DAYLIGHT. FLOOR BY OTHERS ADDTIONAL LATERALS AS RECOMMENDED FDN WALL, ryP. REINFORCEMENT NOT SHOWN MOISTURE BARRIER. 6-MIL MINIMUM, ATTACH TO FOUNDATION WALL A MINIMUM OF 6'ABOVE votDS oR GRAVEL (WHTCHEVER tS GREATER). CONTINUE BELOW PIPE AND UP SIDE OF TRENCH AS SHOWN. 165 2nd St. S.lY., Lowlond. Colorodo 80537 Tols: (970) 667-8010En oineerin o Coiporotiofi TYPICAL PERIMETER DRAIN RECOMMENDATIONS SITE CONDITIONS MAY WARRANT REVISIONS TO TYPICAL DETAILS Scale: N.T.S.APPENDIX 2 10'ro 12' APPENDIX 3 Moisture-Densitlz Determination Representative samples of the materials to be used for fill shall be furnished by the contractor atleast seventy two (72) hours prior to compaction testing. Samples with higher moisture contentswill require extra time for test results due to the required drying for samplJpreparation. Tests todetermine the optimum moisture and density of thl given material will be made using methodsconforming to the most recent procedures of ASTM D698 (standard proctor) or other approvedmethods' whichever may apply. copies of the Proctor curves will be furnished to the contractor.These test results shall be the basis of control for the field moisture/density tests. Materials The soils used for compacted fill shall be selected or approved by the Engineer. The material shallbe free of vegetation, topsoil or any other deleterious materials. The material should be relativelyimpervious and non-swelling for the depth specified in the soils report with no material greaterthan six (6) inches in diameter. Site Preparation All timber, logs, trees, brush and rubbish shall be removed from the area and disposed in a mannerapproved by the local goveming agency. All vegetation and a substantial amount of topsoil shallbe removed from the surface upon which the fill is to be placed. where applicable, the surfaceshall then be scarified to a depth of at least six (6) inches, moistened or driedas necessary to allowfor uniform compaction by the equipment being used. The scarified surface shall be compactedto not less than 95%o of maximum dry density based on ASTM D69g, or to such other density asmay be determined appropriate for the materials and conditions and acceptable to the Engineer.Fill shall not be placed on frozen or muddy ground. Moisture The fill material, while being compacted should contain, as nearly as practical (typically +l- 2%o),the optimum amount of moisture as determined by the Standard proctor Test ASTM D6gg, orother approved method. The moisture shall be uniform throughout the fill material. The effortrequired for optimum compaction will be minimized by keeping soils near optimum moisturecontents' Freezing temperatures andlor inclement weather conditions may impede moisturecontrol and compaction operations. Placement of Fill The Geotechnical Engineer shall be retained to supervise the placement of fill material. The fillmaterial shall be placed in uniform layers and be compacted to not less than 95o/o of maximum drydensity based on ASTM D698, or to such other densiiy as may be determined appropriate for thematerials and conditions and acceptable to the Engineer. Prior to compacting, each layer shallhave a maximum loose layer height of twelve (12) inches (or as dictated by the compactionequipment andlot soil conditions) with the surface relatively level. Test areas are recommended to determine the optimum layer thickness. Thinner lifts may be necessary in order to achieve therequired compaction. Compacted layer thickness shall not exceed six (6) inches. Each twelve(12) inches of compacted fill shall be approved by the Engineer prior to placing succeeding lifts. Fill shall be compacted with machinery appropriate for the type of earthen material being installed.Granular materials shall be compacted with vibratory type machinery. clay and silt material shallbe compacted with a sheepsfoot or other segmented pad type compaction equipment. ,,Wheel rolling" is not considered an appropriate method to achieve the ,..o*rrr"rrded compactionspecifications' "Wheel rolling" is not recommended for extensive areas or depths and cannot berelied upon to give uniform results. Moisture and Density Testing It is the contractor's responsibility to contact the Engineer with a minimum of 24-hours notice toschedule compaction testing. The density and moisture content of each layer of compacted fillwill be determined by the Engineer, or qualified technician, in accordance with ASTM D693g(nuclear method), or other approved method. If the tests show inadequate density, that layer, orportion thereof, shall be reworked until the required conditions are obtained. Additional layersshall not be placed until each underlying lift has been approved. The results of all density testswill be furnished to both the owner and the contractor uv irr. Engineer.