The URL can be used to link to this page

Home My WebLink AboutSubsurface Investigation & OWTS Design.pdf June 13, 2014 Project No. 1731 Caleb Edelman edelmancm@yahoo.com Subsurface Investigation and Onsite Wastewater Treatment System Design 2-Bedroom Residence + 1 Future Bedroom TBD Hwy 82 Garfield County, Colorado Caleb, ALL SERVICE septic, LLC completed a subsurface investigation and designed an onsite wastewater treatment system (OWTS) design for the proposed residence. The design dated July 7, 2010 should be discarded and this design, specifying construction of a drywell, must be followed. This design must be submitted to Garfield County Community Development Department prior to June 30, 20144. The property is located outside of Glenwood Springs, in an area where OW TSs and wells are necessary. SITE CONDITIONS The 5.63 acre property is currently undeveloped and a 2-bedroom residence is proposed. A well was drilled to the south of the driveway. This well is greater than 100 -feet from the proposed drywell. Vegetation on the property consists of pinion and juniper trees, sage brush, and grasses. The property is on a hillside with slopes ranging from 20 to 40 percent in the area of the proposed development. The hillside slopes to the west toward Highway 82. SUBSURFACE The subsurface was investigated by HP Geotech with results documented in a report dated May 19, 2010. Four pits were dug at various locations on the property. The material encountered in all pits consisted of gravel with cobbles and boulders, sandy, silty, medium dense, slightly moist, red angular rock. A sample was taken from a depth of approximately 5 to 7.5-feet from Pit 4 and a gradation analysis run. The material consisted of 58% gravel, 28% sand, and 14% silt and clay. The HP Geotech report is enclosed. All Service Septic ran a percolation test on June 30, 2010. The test resulted in an average percolation rate of 20 minutes per inch (MPI). This test was conducted south and down-gradient of the proposed drywell location. Percolation Test and Soil Data Form – Table 1 results are also enclosed. The subsurface was further investigated on June 3, 2014 by digging one 18-foot profile pit. The materials encountered in the profile pit consisted of red, medium dense, slightly moist gravelly, silty sand with some angular cobbles to the maximum depth explored 18.0-feet. No bedrock or groundwater was encountered. 20 MPI will be used to size the OWTS. Using a long term acceptance rate (LTAR) of 1.1 gallons per square foot results in similar sizing requirements. See Sizing Comparison Table below. Page 2 Profile Pit Observed June 3, 2014 DESIGN SPECIFICATIONS The OWTS design is based on 3-bedrooms to allow for the addition of a future bedroom. An average daily wastewater flow of 450 GPD will be used. Sizing Comparison Table Absorption Area LTAR = 1.1 gal/ sq ft/ day 614 square feet Perc Rate = 20 MPI 604 square feet A 1000-gallon, two-compartment septic tank with an H-20 rated lid and effluent filter on the outlet tee must be installed. The effluent pipe from the septic tank to the drywell will run down the driveway. Schedule 40 pipe or better should be placed in a trench bedded with screened rock and a minimum fall of 1%. For greater protection from freezing, we recommend placing Blue Board insulation over the pipe. Effluent will gravity flow to a drywell 12’ x 12’ x 10-feet. Depth of the drywell must be measured below the inlet pipe. Total square footage of the drywell will be 624 square feet. The drywell will consist of clean, graded rock ranging from ½” to 2 ½” in diameter. The rock will extend from the bottom of the well to at least 2” above the inlet pipe. The sidewalls of the drywell will be scarified. A covering of geotextile fabric will be placed over the aggregate before the drywell is covered with soil. The backfill material shall be graded to deflect precipitation and surface drainage. The drywell must be accessible from grade for future monitoring. Page 3 The component manufacturers are typical of applications used by contractors and engineers in this area. Alternatives may be considered or recommended by contacting our office. Construction must be according to Garfield County Sewage Disposal Regulations, the Individual Sewage Disposal (ISDS) Permit provided by Garfield County Building Department, and this design. REVEGETATION REQUIREMENTS An adequate layer of good quality topsoil capable of supporting revegetation shall be placed over the entire disturbed are of the OWTS installation. A mixture of native grass seed that has good soil stabilizing characteristics (but without taproots), provides a maximum transpiration rate, and competes well with successional species. No trees or shrubs, or any vegetation requiring regular irritation shall be plated over the area. Until vegetation is reestablished, erosion and sediment control measures shall be implemented and maintained on site. The owner of the OWTS shall be responsible for maintaining proper vegetation cover. OPERATION INFORMATION AND MAINTENANCE The property owner shall be responsible for the operation and maintenance of each OWTS servicing the property. The property owner is responsible for maintaining service contracts for manufactured units, alternating absorption systems, and any other components needing maintenance. Geo-fabrics or plastics should not be used over the absorption area. No heavy equipment, machinery, or materials should be placed on backfilled absorption area. Livestock should not graze on the absorption area. Plumbing fixtures should be checked to ensure that no additional water is being discharged to OWTS. For example, a running toilet or leaky faucet can discharge hundreds of gallons of water a day and harm an absorption area. The homeowner should pump the septic tank every two years, or as needed gauged by measurement of solids in the tank. Garbage disposal use should be minimized, and non-biodegradable materials should not be placed into the OWTS. Grease should not be placed in household drains. Loading from a water softener should not be discharged into the OWTS. No hazardous wastes should be directed into the OWTS. Mechanical room drains should not discharge into the OWTS. The OWTS is engineered for domestic waste only. ADDITIONAL CONSTRUCTION NOTES If design includes a pump, air release valves and weep holes should be installed to allow pump lines to drain to minimize risk of freezing. Excavation equipment must not drive in excavation of the absorption area due to the potential to compact soil. Extensions should be placed on all septic tank components to allow access to them from existing grade. Backfill over absorption area must be uniform and granular with no material greater than minus 3-inch. INSTALLATION OBSERVATIONS ALL SERVICE septic, LLC must view the OWTS during construction. The OWTS observation should be performed before backfill, after placement of OWTS components. Septic tanks, distribution devices, pumps, dosing siphons, and other plumbing, as applicable, must also be observed. ALL SERVICE septic, LLC should be notified 48 hours in advance to observe the installation. Page 4 LIMITS: The design is based on information submitted. If soil conditions encountered are different from conditions described in report, ALL SERVICE septic, LLC should be notified. All OW TS construction must be according to the county regulations. Requirements not specified in this report must follow applicable county regulations. The installer should have documented and demonstrated knowledge of the requirements and regulations of the county in which they are working. Please call with questions. Sincerely, ALL SERVICE septic, LLC Reviewed By: Carla Ostberg, MPH, REHS N ~ I I I O' 50' 100' Scale: 1" = 100'-0" Hll ~rnti~( ;~1 ll '"'' '""": Elev. al Edge o; i Pavement 942.56 ' Spot Elevation 6043.30' 33 Four Wheel Drive Road Carbondale, CO 81623 970.309.5259 Found, Rebar LS. No. ~ -0,,, 0,- -<> o~ "'~ "'->,- + <} C;. "'-> 0,,, o~...-., ?Q- 0 Spot Elevation 16051.53' ~ ~ ?~ 0 ~- ""°?' <C, ~ Spot Elevation 605827' ~ 0 ~ ~ () 5 ol E!evalio~ \ p 6092.43 \ Sect?:on 20 1/2 height of bwlding whiche ver is greater) 627.94 3-BED-:-- - - - - - - - IRES . Cl • "'.9 vection ~, 246.90' --------~-" Acres -!--/- ,.,_ ~Ji',.. ~ ~- ? '6... :c, *- F!owline Ditch ~ ~ /) :l; Found, Bross Cap LS. No. 7734 :;i Sect?:on 21 Found, Brass Cop ,,,,. .en " ['< ~ Sect?:on 28 BLJlf Lego! Description A Parcel of land situated in Lot !, Section 29, Township 7 South, Range 88 West of the Sixth Principal Meridian, County of Garfield, State of Colorado, being more particularly described as follo ws : Beginning at a found Brass Cap LS. 7 734 in place for the Northeast Comer of Section 29, Township 7 South, Range 88 West, whence a found B.L.M. Aluminum Cap in place for the East ~ corner for said Section 29 bears S00"27'51"W a distance of 2677.86 feet, with all bearings contained herein being relative thereto; Thence S00'27'57 ''w along the east line of said Section 29 a distance of 781. 74 feet to a point on the Northeasterly right-of-way for Colorado State Highway No. 82; thence along the Northeasterly right -of-way line for said Colorado State High way No. 82 the following 5 courses: 1) 28.11 feet along the arc of a curve concave to the Southwest, ha ving a radius of 3065.00 feet and whose chord bears N38 '43'59"W a distance of 28.11 feet. 2) N38 "44'46"W a distance of 310. 40 feel; 3) N39'45'46"W a distance of 360.00 feet; 4) N25 '43'46 "W a distance of 206.20 feel; 5) N52'52'22 "W a distance of 705.26 feet to a point on the North line of said Section 29; Thence S89 '13'51 "E along the North line of said Section 29 a distance of 621.94 feet to the poin t of beginning. County of Garfield State of Colorado DRAWINGS MUST BE USED IN CONJUNCTION WITH DESIGN LETTER DATED 6/13/14 (il SITE PLAN . m _ Found, Rebar & Cap LS. 13933 Edelman Residence TBD Highway 82 Garfield County , Colorado Project Number: 1731 Date: 06/13/14 Designed By : CBO Reviewed By : RHP Drawn By : ANG W1.0 Sheet 1 of 3 N ~ I I I O' 10' 20' Scale : 1" = 20'-0" Hll ~rnti~( ~ 33 Four Wheel Drive Road Carbondale, CO 81623 970 .309 .5259 L \ \ 12' x 12' x 10' DEEP DRYWELL 1 \ WITH 4' DIA PERFORATED 0 P1 0 P3 CONCRETE RINGS 4" DIA SCH 40 OR BETTER SEWER LINE ' MIN SLOPE TO DRYWELL) OP2 3-BEDROOM RESIDENCE 4" DIA SDR-35 SEWER LINE WITH CLEANOUT (2% MIN SLOPE TO TANK) (2'i PROPOSED SITE. PL_~~ Edelman Residence TBD Highway 82 Garfield County , Colorado Project Number: 1731 I DESIGN 3-BEDROOM RESIDENCE (75 GAL/PERSON/DAY x 2 PERSONS/BEDROOM x 3 BEDROOMS) AVERAGE DAILY FLOW= 450 GALLONS DESIGN FLOW = Q = 1.5 x 450 = 675 GALLONS TANK: 675 x 30 HOUR RETENTION TIME = 844 GALLONS USE 1000-GALLON, TWO-COMPARTMENT TANK ABSORPTION AREA: PERCOLATION RA TE = 20 MPI CALCULATED ABSORPTION AREA = Q/5 X SQRT perc rate = 604 SF NO REDUCTIONS I DRYWELL 12' WIDE X 12' LONG X 10' DEEP BELOW THE INLET= 624 SF Date : 06/13/14 Designed By : CBO I W 2. Q Reviewed By : RHP Drawn By : ANG I Sheet 2 of 3 PLAN VIEW DRYWELL DRAIN FIELD SPECIFICATIONS '-+---DISPERSAL GRAVEL SHOULD 12' BE 1/2" TO 2 1/2" ~SIDES OF EXCAVATION " OBSERVATION PIPE WITH PVC CAP CROSS SECTION -----CONCRETE LID BERM OR SWALE NATURAL GRADE INLET FROM SEPTIC TANK EXTENT OF 10' 1' SLOPE FOR DRAINAGE . . . . . . . . . . . . . . . . . . WITH MANHOLE COVER ---GEO-FABRIC DISPERSAL GRAVEL __..-SLOTTED PVC OBS . PIPE TO EXTEND TO BOTTOM OF DRYWELL EXCAVATION--L__, , 1 , 12' --5 FOOT DIAMETER PLACE AN 8-INCH BED OF GRAVEL~ CONCRETE PRIOR TO PLACING CONCRETE RINGS PERFORATED RINGS FOR STABILITY Hll ~rnti~( 33 Four Wheel Drive Road Carbondale, CO 81623 970 .309 .5259 0 DRYWELL DETAILS NOT TO SCA!£ FINISHED GRADE ,----SLIP-ON PVC CAP DO NOT GLUE .. ' I l EFFLUENT LINE -4" SEWER LINE -l I SCHEDULE 40 OR 4" SOR 4" SCHEDULE 35 P.V.C . 40 P.V.C . INSULATED COPPER TRACER WIRE MAY BE INSTALLED TO LOCATE LINE IN FUTURE 0 CLEANOUT DETAIL NOT TO SCALE Septic Tank with the Addition of an Effluent Filter -1000 Gallon, 2-Comp. . Concrete Risers~ Slope Ground Away From Risers Top of tee to come to 1 " from top of tank lid Inlet Tee ."J I ~ • I Edelman Residence TBD Highway 82 Garfield County, Colorado Project Number: 1731 ~ '\J 2" J Liquid Level ®TANK DETAIL NOT TO SCALE Filter Cartridge Handle (field cut to desired height) Tank Adapter (cast or bolted) 1,----Vent Orifice Effluent Discharge ,.......__ __ Modulating Discharge Orifices f-+-+----Vault Inlet Ports Filter Cartridge '----Effluent Filter Date : 06/13/14 Designed By : CBO I W 3. Q Reviewed By: RHP Drawn By: ANG I Sheet 3 of 3 ~tech HEPWORTH -PAWLAK GEOTECHNICAL May 19, 2010 ECOS Attn: Caleb Edelman P.O. Box 11936 Aspen, Colorado 81612 I kpwurth -P.m l.1k G1:n t t:l h n 1c,1 I, Inc . 5Q2L1 Crn111t\ l\1>;1d 154 l ~le m niocl 5prin!!', Cnl,,1 ,1d1) S l 6Q I l'h, 111c·: 9(\).44 5. /l1~~ r:a,: 97L1 .l)4'i ·S4'i4 c m.u l hrt:eo" hpt!e11ted1 c.:11111 Job No . 110 081A Subject: Subsoil Study for Foundation Design, Proposed Residence and ADU, 5.63 Acre Parcel, Near Mushroom Rock, Highway 82, Garfield County, Colorado Dear Mr. Edelman: As requested , Hepworth-Pawlak Geotechnical, Inc. performed a sub so il study for design of foundations at the subject site. The study was conducted in accordance with our agreement for geotechnical engineering services to ECOS dated April 12, 2010 and verball y amended by Caleb Edelman on May 10, 2010 to include the residence site. The data obtained and our recommendations based on the proposed construction and subsurface conditions encountered are presented in this report. Evaluation of potential geologic hazard impacts and possible mitigation are beyond the scope of this study. Proposed Construction : The building plans for the propo sed residence are conceptual. Typical construction in the area consists of 1 and 2 story wood frame structures above a craw lspace o r walkout basement with an attached garage. Basement and garage floors would be slab-on-grade. The ADU wi ll be 1 story wood frame above a walkout basement. Ground floor will be slab-on-grade. The building locations are shown on Figure 1. Cut depths are expected to range between about 3 to 10 feet. Foundation loadings for this type of construction are assumed to be relatively light and typical of the proposed type of construction. Driveway access will be from the existing dirt road near the northwest comer of the property. If bui ld ing conditions or foundation loadings are significantly different from those described above, we should be notified to re-evaluate the recommendations presented in this report. r,uke r 30 3-841 -7 119 • Colorndn Spr i n~~ 719-6 3 3-5 56 2 • Si h e rthn rnc 970-468-1989 -2- Site Conditions: The site was vacant of structures and is accessed by a dirt road from State Highway 82. Vegetation consists ofpiiion and juniper trees, sage brush, grass and weeds. The site is located on a west facing hillside above State Highway 82. The ground surface slopes down at a grade of about 33 percent in the residence building area and 26 percent at the ADU site and varies from 22 percent to 38 percent across the lower part of the property. A debris flow several feet thick was observed to have knocked down a steel post and wire fence northeast of the ADU site. A deep debris flow channel was observed south of the residence site. Maroon Formation bedrock outcrops above the building areas on slopes greater than 45 percent. Boulders up to 8 feet in size were observed on the site. Subsurface Conditions: The subsurface conditions at the site were evaluated by excavating two exploratory pits at the residence site and two exploratory pits at the ADU site. Approximate locations of the pits are shown on Figure I. The logs of the pits are presented on Figure 2. The subsoils encountered, below about 6 to 12 inches of topsoil, consist of silty sandy gravel with cobbles and boulders. Results of swell-consolidation testing performed on relatively undisturbed samples of silty sand with gravel matrix, presented on Figure 3, indicate low compressibility under existing moisture conditions and light loading and low to moderate compression under additional loading after wetting. One of the samples showed a low collapse potential (settlement under constant load) when wetted. Results of a gradation analysis performed on a sample of silty sandy gravel (minus 5 inch fraction) obtained from the site are presented on Figure 4. No free water was observed in the pits at the time of excavation and the soils were slightly moist to moist. Site Development: The development area appears to be impacted by rockfall and debris flow hazards. We recommend that the geologic hazards impacting the site be evaluated to determine the feasibility of construction and, if needed, mitigation plans be developed prior to building on the site. Provided the hazards are low or can be mitigated, construction on the site can be based o the following design recommendations. Foundation Recommendations: Considering the subsoil conditions encountered in the exploratory pits and the nature of the proposed construction, we recommend spread footings placed on the undisturbed natural soil designed for an allowable soil bearing pressure of2,000 psffor support of the proposed residence and ADU. The matrix soils tend to compress after wetting and there could be some post-construction foundation settlement. Footings should be a minimum width of 16 inches for continuous walls and 2 feet for columns. Loose and disturbed soils and fill from site grading encountered at the Job No. 110 OSIA ~tech - 3 - foundation bearing level within the excavation should be removed and the footing bearing level extended down to the undisturbed natural soils. Holes below footing grade from boulder removal should be backfilled with concrete or structural fill such as % inch road base compacted to at least 98% of the standard Proctor density. Exterior footings should be provided with adequate cover above their bearing elevations for frost protection. Placement of footings at least 36 inches below the exterior grade is typically used in this area. Continuous foundation walls should be reinforced top and bottom to span local anomalies such as by assuming an unsupported length of at least 12 feet. Foundation walls acting as retaining structures should be designed to resist a lateral earth pressure based on an equivalent fluid unit weight of at least 50 pcffor the on-site soil as backfill. Floor Slabs: The natural on-site soils, exclusive of topsoil, are suitable to support lightly loaded slab-on-grade construction. To reduce the effects of some differential movement, floor slabs should be separated from all bearing walls and columns with expansion joints which allow unrestrained vertical movement. Floor slab control joints should be used to reduce damage due to shrinkage cracking. The requirements for joint spacing and slab reinforcement should be established by the designer based on experience and the intended slab use. A minimum 4 inch layer of free-draining gravel should be placed beneath basement level slabs to facilitate drainage. This material should consist of minus 2 inch aggregate with less than 50% passing the No. 4 sieve and less than 2% passing the No. 200 sieve. All fill materials for support of floor slabs should be compacted to at least 95% of maximum standard Proctor density at a moisture content near optimum. Required fill can consist of the on-site granular soils devoid of vegetation, topsoil and oversized rock. Underdrain System: Although free water was not encountered during our exploration, it has been our experience in the area that local perched groundwater can develop during times of heavy precipitation or seasonal runoff. Frozen ground during spring runoff can create a perched condition. We recommend below-grade construction, such as retaining walls, crawlspace and basement areas, be protected from wetting and hydrostatic pressure buildup by an underdrain system. The drains should consist of drainpipe placed in the bottom of the wall backfill surrounded above the invert level with free-draining granular material. The drain should be placed at each level of excavation and at least I foot below lowest adjacent finish grade and sloped at a minimum I% to a suitable gravity outlet. Free-draining granular material used in the underdrain system should contain less than 2% passing the No. 200 Job No. 110 081A - 4 - sieve, less than 50% passing the No. 4 sieve and have a maximum size of2 inches. The drain gravel backfill should be at least 1 Yi feet deep. Surface Drainage: The following drainage precautions should be observed during construction and maintained at all times after the residence and ADU have been completed: 1) Inundation of the foundation excavations and underslab areas should be avoided during construction. 2) Exterior backfill should be adjusted to near optimum moisture and compacted to at least 95% of the maximum standard Proctor density in pavement and slab areas and to at least 90% of the maximum standard Proctor density in landscape areas. Free-draining wall backfill should be capped with about 2 feet of the on-site, finer graded soils to reduce surface water infiltration. 3) The ground surface surrounding the exterior of the building should be sloped to drain away from the foundation in all directions. We recommend a minimum slope of12 inches in the first 10 feet in unpaved areas and a minimum slope of3 inches in the first 10 feet in pavement and walkway areas. Swales may be needed uphill to direct surface runoff around the structures. 4) Roof downspouts and drains should discharge well beyond the limits of all backfill. 5) Landscaping which requires regular heavy irrigation should be located at least 10 feet from the building. Consideration should be given to the use ofxeriscape to limit potential wetting of matrix soils below the foundation caused by irrigation. Limitations: This study has been conducted in accordance with generally accepted geotechnical engineering principles and practices in this area at this time. We make no warranty either express or implied. The conclusions and recommendations submitted in this report are based upon the data obtained from the exploratory pits excavated at the locations indicated on Figure 1 and to the depths shown on Figure 2, the proposed type of construction, and our experience in the area. Our services do not include determining the presence, prevention or possibility of mold or other biological contaminants (MOBC) developing in the future. If the client is concerned about MOBC, then a professional in this special field of practice should be consulted. Our findings include interpolation and extrapolation of the subsurface conditions identified at the exploratory pits and variations in the subsurface conditions may not become evident until excavation is performed. If conditions encountered during construction appear different from those described in this Job No. 110 081A ~tech - 5 - report, we should be notified at once so re-evaluation of the recommendations may be made. This report has been prepared for the exclusive use by our client for design purposes. We are not responsible for technical interpretations by others of our information. As the project evolves, we should provide continued consultation and field services during construction to review and monitor the implementation of our recommendations, and to verify that the recommendations have been appropriately interpreted. Significant design changes may require additional analysis or modifications to the recommendations presented herein. We recommend on-site observation of excavations and foundation bearing strata and testing of structural fill by a representative of the geotechnical engineer. If you have any questions or if we may be of further assistance, please let us know. Respectfully Submitted, HEPWORTH -PAWLAK GEOTECHNICAL, INC. Louis Eller Reviewed by: Daniel E. Hardin, P.E LEE/ksw attachments Figure 1 -Location of Exploratory Pits Figure 2-Logs of Exploratory Pits Figure 3 -Swell-Consolidation Test Results Figure 4 -Gradation Test Results Table 1 -Summary of Laboratory Testing cc: Kurtz and Associates -Attn: Brian Kurtz Job No. 110 OSIA ~tech APP ROXIMATE SCA LE 1" =120' 110 08 1A ~ He worth-Pawlak Geotechn lc al o~, B£U LO CATI ON OF EXPLORATORY PIT S Figure 1 '§_ Q) 0 0 5 10 LEGEND: PIT 1 ELEV.= 8138' PIT2 ELEV.= 8126' WC=5.3 00=98 -200=36 PIT3 ELEV.= 8132' WC=3.7 00=103 PIT 4 ELEV.= 8144' +4=58 -200=14 0 5 10 ~ ~ ~ r--: ~-~ TOPSOIL; organic sandy silt and gravel with cobbles and boulders, loose to medium dense, slightly moist. reddish brown. GRAVEL (GM); with cobbles and boulders, sandy, silty, medium dense, slightly moist, red, angular rock. 2" Diameter hand driven liner sample. Disturbed bulk sample. T Practical digging refusal. NOTES: 1. Exploratory pits were excavated on May 10, 2010 with a Cat 303.SC trackhoe. 2. Locations of exploratory pits were measured approximately by pacing from features shown on the site plan provided. 3. Elevations of exploratory pits were obtained by interpolation between contours shown on the site plan provided and checked by hand level. 4. The exploratory pit locations and elevations should be considered accurate only to the degree implied by the method used. 5. The lines between materials shown on the exploratory pit logs represent the approximate boundaries between material types and transitions may be gradual. 6. No free water was encountered in the pits at the time of excavating. Fluctuation in water level may occur with time. 7. Laboratory Testing Results: WC = Water Content (%) DD = Dry Density (pcf) +4 = Percent retained on the No. 4 sieve -200 = Percent passing No. 200 sieve 110081A c~ HEPWORTH•PAWLAK GEOTECHNJCAL LOGS OF EXPLORATORY PITS Figure 2 Moisture Content = 3.2 percent Dry Density = 106 pcf Sample of: Silty Sand with Gravel From: Pit 1 at 6 Feet 0 1 ~ ----Compression '~ ( upon 2 wetting * " c "' 0 ·c;; (/) 3 ~ Q. \ E 0 (_) 4 \ 5 6 0.1 1.0 10 100 APPLIED PRESSURE -ksf . ·- Moisture Content = 3.7 percent Dry Density = 103 pct Sample of: Silty Sand with Gravel From: Pit 3 at 3 Feet 0 * '--.. ~ c 1 0 ·c;; 0 ""' (/) ~ i\ Q. E 2 0 No' movement (_) upon 3 wetting -•" --· 0.1 1.0 10 100 APPLIED PRESSURE -ksf c~£tech - 110081A SWELL-CONSOLIDATION TEST RESULTS Figure 3 Heoworth-Pawlok Geotechntcal 0 w z ~ w a:: I-z w (.) a:: w a_ I HYDROMETER ANALYSIS I SIEVE ANALYSIS I TIME READINGS I 24HR. 7 HR O 45 MIN. 15 MIN. 60MINJ9MIN.4 MIN. 1 MIN. #200 U.S. STANDARD SERIES I CUEAR SQUARE OPENINGS #100 #50 #30 #16 #8 #4 3/8" 3/4" 1 1/2' 3" 5'6' I B" 100 10 90 20 80 30 70 40 60 50 50 60 40 70 30 80 20 90 10 0 100 .001 .002 .005 .009 .019 .037 .074 .150 .300 .600 1.18 2.36 4. 75 9.5 19.0 37.5 76.2 152 203 12.5 127 DIAMETER OF PARTICLES IN MILLIMETERS CLAYTOSILT SAND GRA"El I MEDIUM CCJAASE FlNE 1 COARSE COBBLES GRAVEL 58 % SAND 28 % SILT AND CLAY 14 % LIQUID LIMIT % PLASTICITY INDEX % SAMPLE OF: Silty Sandy Gravel with Cobbles FROM: Pit 4 at 5 to 7 }'2 Feet (!) z iii (/) <( a_ I-z w (.) a:: w a_ 110081A c~~ GRADATION TEST RESULTS Figure 4 HEPWORTH·PAWLAK GEOTECHNICAL SAMPLE LOCATION NATURAL NATURAL MOISTURE DRY PIT DEPTH CONTENT DENSITY (ft) (%) (pcf) 1 6 3.2 106 2 3 5.3 98 3 3 3.7 103 4 5to71h HEPWORTH-PAWLAK GEOTECHNICAL, INC. . TABLE 1 SUMMARY OF LABORATORY TEST RESULTS GRADATION ATTERBERG LIMITS PERCENT GRAVEL SAND PASSING LIQUID PLASTIC NO. 200 LIMIT INDEX (%) (%) SIEVE 1%) (%) 36 58 28 14 Job No. 110 081A UNCONFINED COMPRESSIVE SOIL OR STRENGTH BEDROCK TYPE (PSF) Silty Sand with Gravel Silty Sand with Gravel Silty Sand with Gravel Silty Sandy Gravel with Cobbles GARFIELD COUNTY DEPT. OF ENVIRONMENTAL HEALTH AND NATURAL RES. Percolation Test and Soils Data Form - TABLE 1 - PROJECT 1731 PROFILE PIT Date of Test: 6/30/2010 Per HP Geotech Report attached No Bedrock or Groundwater was Encountered Hole No. Hole Depth (in.) Interval (min.) Measurement at Start of Interval (in.) Measurement at End of Interval (in.) Change (in.)Percolation Rate (min./in.) MPI 1 24 10 2.50 4.00 1.50 10 4.00 5.50 1.50 10 5.50 7.00 1.75 fill 10 1.75 3.00 1.25 10 3.00 3.75 0.75 27 10 3.75 4.75 1.00 2 31 10 1.50 3.50 2.00 10 3.50 4.50 1.00 10 4.50 dry fill 10 3.50 5.00 1.50 10 5.00 5.75 0.75 10 5.75 6.50 0.75 14 3 22 10 3.00 4.50 1.50 10 4.50 5.50 1.00 fill 10 1.50 3.00 1.50 10 3.00 4.25 1.25 10 4.25 5.50 1.25 10 5.50 6.00 0.50 20 AVG = 20 MPI Performed by All Service Septic, LLC