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HomeMy WebLinkAboutOWTS Design Report 04.24.2019K -LA Kumar & Associates, Inc. Geotechnical and Materials Engineers and Environmental Scientists 5020 County Road 154 Glenwood Springs, CO 81601 phone: (970) 945-7988 fax: (970) 945-8454 email: kaglenwood@kumarusa.com An Employee Owned Company www.kumarusa.com Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado 001. Asse[rAlP:. 30 �Irdye p �rsoi, •• i u.w8ki,m.rufa.wm 9-201 ONSITE WASTEWATER TREATMENT SYSTEM DESIGN PROPOSED OFFICE BUILDING LOT 9, BIG R COMMERCIAL PARK 28485 HIGHWAY 6 GARFIELD COUNTY, COLORADO PROJECT NO. 19-7-143.02 APRIL 24, 2019 PREPARED FOR: Z CONSTRUCTION ATTN: LARRY ZUGSCHWERDT 0311 HANDY DRIVE CARBONDALE, COLORADO 81623 (icon structionbuilders( email.coni) TABLE OF CONTENTS INTRODUCTION - 1 - PROPOSED CONSTRUCTION - 1 - SITE CONDITIONS - 1 - SUBSURFACE CONDITIONS - 2 - OWTS ANALYSIS - 4 - DESIGN RECOMMENDATIONS - 4 - SOIL TREATMENT AREA - 5 - OWTS COMPONENTS - 6 - OWTS OPERATION AND MAINTENANCE - 9 - OWTS HOUSEHOLD OPERATION - 9 - OWTS MAINTENANCE - 10 - OWTS CONSTRUCTION OBSERVATION - 10 - LIMITATIONS - 11 - FIGURES FIGURE 1 - OWTS SITE PLAN FIGURE 2 - USDA GRADATION TEST RESULTS FIGURE 3 - SOIL TREATMENT AREA CALCULATIONS FIGURE 4 - SOIL TREATMENT AREA PLAN VIEW FIGURE 5 - SOIL TREATMENT ARE CROSS SECTION FIGURE 6 - DISTRIBUTION LINE CLEANOUT DETAIL ATTACHMENTS VALLEY PRECAST 1,000 GALLON, THREE -CHAMBER SEPTIC TANK DETAIL ORENCO PF3005 PUMP PERFORMANCE CURVE Kumar & Associates, Inc. Project No. 19-7-143.02 INTRODUCTION This report provides the results of an onsite wastewater treatment system (OWTS) design for the proposed office building located on Lot 9, Big R Commercial Park, 28485 Highway 6, east of Rifle, Garfield County, Colorado. The purpose of the report is to provide design details for the OWTS in accordance with the 2018 Garfield County Building Department Onsite Wastewater Treatment System Regulations and the Colorado Department of Public Health and Environmental Regulation #43. The services were performed as part of our agreement for professional services to Z Construction dated February 15, 2019. We previously conducted a subsoil study for foundation design for the office building and presented our findings in a report dated March 12, 2019, Project No. 19-7-143. PROPOSED CONSTRUCTION The building will be a single story, wood frame structure, about 28 by 40 feet in plan size, and located in the extreme southern part of the lot as shown on Figure 1. The floor will be structurally supported over crawlspace with a finish elevation slightly above the existing ground surface. The proposed soil treatment area (STA) for the OWTS will be located to the north of the pavement area shown on Figure 1. Water service is provided by a well near the southeast corner of the lot, see Figure 1. If proposed construction is different than that described, we should be contacted to re-evaluate our design recommendations. SITE CONDITIONS The lot is currently used for equipment and materials storage and has undergone some minor grading and concrete and asphalt paving. The minor grading appeared to consist primarily of gravel surfacing. The terrain is relatively flat with a slight slope down to the south at about 1% Kumar & Associates, Inc. Project No. 19-7-143.02 2 grade. There are no nearby surface water features. We are not aware of any nearby water wells in the except for the one on the subject Lot 9. SUBSURFACE CONDITIONS The field exploration for the OWTS was conducted on April 4, 2019. Four profile pits (Profile Pits 1, 2, 3 and 4) were excavated with a backhoe at the approximate locations shown on Figure 1 to evaluate the subsurface conditions at alternate planned soil treatment areas for the OWTS. The pits were logged by a representative of Kumar & Associates. Logs of the profile pits are provided below. Log of Profile Pit 1 Depth USDA Classification 0-1' 0-2' FILL; silty gravel and sand, medium dense, moist, brown. 1'-4' LOAM; moderate blocky structure, medium stiff, moist, brown. 4'-8' LOAM; moderate blocky structure, medium stiff, moist, brown. SANDY LOAM; massive structure, medium stiff, moist, brown • Disturbed bulk samples obtained from 3 to 4 feet and 6 to 7 feet. • Bottom of pit @ 8 feet. • No. free water or redoximorphic 'moire.; observed at time of pit excavation. Log of Profile Pit 2 Depth USDA Classification 0-1' 0-2' FILL; silty gravel and sand, medium dense, moist, brown. FILL; silty gravel and sand, medium dense, moist, brown. 2'-4' 4'-8' LOAM; moderate blocky structure, medium stiff, moist, brown. SANDY LOAM; massive structure, medium stiff, moist, brown 4'-8' Disturbed bulk samples obtained from 6 to 7feet. SANDY LOAM; massive structure, medium stiff, moist, brown • • Bottom of pit @ 8 feet. No free water or redoximorphic. features observed at time ofpit excavation. Log of Profile Pit 3 Depth USDA Classification 0-1' FILL; silty gravel and sand, medium dense, moist, brown. 1'-4' LOAM; moderate blocky structure, medium stiff, moist, brown. 4'-8' SANDY LOAM; massive structure, medium stiff, moist, brown • Disturbed bulk samples obtained from 6 to 7feet. Kumar & Associates, Inc. Project No. 19-7-143.02 3 • Bottom of pit @ 8 feet. • No free water or redoximor phic features observed at time of pit excavation. Log of Profile Pit 4 Depth USDA Classification 0'-4' LOAM; moderate blocky structure, medium stiff, moist, brown. 4'-8' SANDY LOAM; massive structure, medium stiff, moist, brown • Disturbed bulk samples obtained from 2 to 3 feet. • Bottom of pit @ 8 feet. • No free water or redoximor.hic features observed at time o .it excavation. The soils encountered in profile pits consisted of nil to about 2 feet of man -placed granular fill overlying Loam to a depth of about 4 feet underlain by Sandy Loam to the pit depths of 8 feet. Hydrometer and gradation analyses were performed on a disturbed bulk sample of the soils from Profile Pit 4 from 2 to 3 feet depth with the results provided on Figure 2. The tested sample (minus No. 10 size sieve fraction) classified as Loam per the USDA system. Based on the subsurface conditions, the soils have been classified as Soil Type 2A per State regulations. No free water was encountered in the pits nor indications of seasonal high groundwater observed at the time of excavation. In addition to the two profile pits, percolation testing was performed in two shallow holes hand - dug holes in the bottom of backhoe pits adjacent Profile Pits 1 and 4 on April 4, 2019. The percolation rates in the test holes averaged about 20 to 30 minutes per inch (mpi), typical of a Loam to Sandy Loam soil. Percolation test procedures outlined in Colorado Department of Public Health and Environmental Regulation #43 were not utilized and the results were only used for comparison with the soil profile pit evaluations. Based on the subsurface conditions and laboratory testing, the soils at the STA have been classified as Type 2A per State regulations, which equates to a long-term acceptance rate (LTAR) of 0.50 gallons per square foot per day. Kumar & Associates, Inc. Project No. 19-7-143.02 4 OWTS ANALYSIS Based on the site conditions and profile pit evaluations, the evaluated areas should be suitable for a pressure -dosed infiltration disposal system. Due to set -back requirements and the paved storage areas of the site, the STA will need to be located up-slope and to the northeast of the proposed building and existing pavement. The system will consist of chambers in a trench configuration. The STA will be sized for four employees in the proposed office building and an average daily flow of 35 gallons per employee and using an LTAR of 0.50 gallons per square foot per day for the natural soils. The sewage will gravity flow from the office building to the septic tank for primary treatment and then be pressured -dosed on a regular basis to the STA for dispersal and final treatment. The STA will consist of one trench with Infiltrator chambers. Due to the setback distance from the well and the elevation change to the STA, the system needs to be pressure dosed. The pressure - dosing to the STA allows for a reduced field size. A 100 feet minimum setback from the STA and a 50 feet minimum setback from the septic tank are required to the existing well located in the southeast corner of the lot. The set -backs are shown on Figure 1. Based on site measurements, the well appears to be approximately 240 feet from the STA and 55 feet from the septic tank. Also, the STA is about 2 feet higher in elevation than the ground surface at the building site. The location of the STA and septic tank with respect to the well should be confirmed prior to construction to verify adequate set -back. The waterline from the well to the building should have adequate set -back from the OWTS components. DESIGN RECOMMENDATIONS The design recommendations presented below are based on the proposed construction, the site and subsurface conditions encountered and our experience in the area. A layout of the proposed OWTS components is provided on Figure 1. If conditions encountered during construction are different than those that are described in this report, please contact us to re-evaluate our design recommendations. Kumar & Associates, Inc. Project No. 19-7-143.02 5 SOIL TREATMENT AREA • The STA will consist of one trench with 14 Infiltrator Quick 4 Plus Standard chambers placed in the native Loam and Sandy Loam soils. A pressure distribution system will be used to disperse the effluent to the trench on a regular basis. • The STA was sized based on an LTAR of 0.50 gallons per square feet per day. • Each chamber was allowed 12 square feet of area. A 20% reduction in the STA was applied for pressure dosing to a trench and a 30% reduction of the STA size was applied for use of Infiltrator chambers in a trench configuration. The total STA is 168 square feet. Soil treatment area calculations are shown on Figure 3. • Distribution lines, consisting of 1.5 -inch diameter, Schedule 40 piping, with'/8-inch orifice holes drilled at 4 -foot centers near the center of the infiltrators, should be installed along the complete length of the infiltrators, see Figure 4. The distribution lines should be suspended approximately 2 inches from the top surface of the infiltrators by pipe ties. The orifice holes should face up toward the infiltrator surface above. • A %-inch hole should be drilled on the bottom of each end of the distribution pipe to allow for complete drainage of the distribution line following pressure dosing. Install splash plates below drain holes. • The trench should be oriented along ground contours to minimize soil cut and cover. • The base and sidewalls of the trench excavations should be scarified prior to the chamber placement. • A minimum of 12 inches and a maximum of 24 inches of cover soil should be placed over the chambers. • Backfill should be graded to deflect surface water away from the STA and should be sloped at 3 horizontal to 1 vertical or flatter. • Disturbed soil should be re -vegetated as soon as possible with a native grass mix. No trees, shrubs or other plants with deep roots should be planted on or near the STA as this may damage the system piping. • Four -inch diameter inspection ports should be installed vertically into the knockouts provided in the Infiltrator end caps. Install vents at each end of the trench. The inspection port piping should be screwed into the top to the chambers and should not Kumar & Associates, Inc. Project No. 19-7-143.02 - 6 extend down to the ground surface inside the chambers. The inspection ports should extend at least 8 inches above the finished ground surface or be protected in a valve box at finished grade. • A plan view of the STA is presented on Figure 4 and a cross section of the STA is presented on Figure 5. • Cleanouts are required at the end of the distribution line. See Figure 6 for the cleanout detail. OWTS COMPONENTS Recommended OWTS components provided below are based on our design details and our experience with the specific component manufacturers. Equivalent components may be feasible but need to be approved by us prior to construction. Septic Tank • A 1,000 gallon, three -chamber septic tank (1,500 gallons total) can be used for primary treatment and dosing to the STA. The first two chambers of the tank will be utilized for treatment and settling, and the third chamber will contain the dosing pump. A detail of the tank is provided as an attachment to the report. • A submersible effluent pump enclosed in a Biotube Pump Vault will be installed in the third chamber. • The tank must be a minimum of five feet from the office building and from the STA. The tank must be a minimum of 10 feet from any potable water supply lines. The tank must be a minimum of 50 feet from the well. • The tank must be set level. The excavation bottom must be free of large rocks or other objects that could damage the tank during placement. A road base or gravel bedding material may be needed to prevent tank damage during placement and act as a leveling course. • The tank lids must extend to final surface grade and made to be easily located. • Install the tank with 2 feet minimum cover soil for frost protection. Maximum tank soil cover is 4 feet. Kumar & Associates, Inc. Project No. 19-7-143.02 7 Sewer Pipe • The sewer line to the septic tank should not be less than the diameter of the building drains and not less than 4 inches in diameter. • The sewer pipe should have a rating of SDR35 or stronger. • The sewer pipe should be sloped between 2% to 4% to help limit disturbance of solids in the tank and potential sewage bypass of the first chamber of the tank. If a steeper slope is needed, this can be accomplished with vertical step-downs in the sewer line. • A minimum 36 inches of cover soil should be provided over the sewer pipe. Paved areas, patios or other areas without vegetative cover may be more susceptible to frost and we recommend 48 inches of soil cover over the sewer pipe in these areas, and the pipe be insulated on top and sides with 2 -inch -thick blue foam insulation board. If adequate soil cover is not possible, we should be contacted for re-evaluation prior to installation. • The sewer pipe should be double encased with larger diameter Schedule 40 PVC pipe the entire length of the sewer line due to encroachment on the 50 feet setback to the well. The encasing pipe should be sealed at both ends. • The sewer pipe should be bedded in compacted 3/4 inch road base or native soils provided that the native soils contain no angular rocks or rocks larger than 2'/2 inches in diameter to help prevent settlement of the pipe. Sags in the pipe could cause standing effluent to freeze and damage the piping. • Install cleanout pipes within 5 feet of the building foundation, where the sewer pipes bend 90 degrees or more and every 100 feet of sewer pipe. • All 90 -degree bends should be installed using a 90 -degree long -sweep or by using two 45 -degree elbows. • The sewer line location shown on Figure 1 is considered conceptual. We assume that there will be only one sewer line exiting the office building. It is the responsibility of the owner/contractors to locate all sewer line exit locations and connections to the septic tank. We should be notified if there are other sewer lines exiting the building. Effluent Transport Piping • The effluent transport pipe should be 1.5 -inch diameter Schedule 40 piping sloped at a 2% minimum to drain back to the septic tank from the trench. Kumar & Associates, Inc. Project No. 19-7-143.02 8 • The effluent transport pipe should be bedded in compacted % inch road base or native soils provided that the native soils contain no angular rocks or rocks larger than 2Y2 inches in diameter to help prevent settlement of the pipe. Sags could cause standing effluent to freeze and damage to the piping. • A minimum 18 inches of cover soil should be provided over the effluent transport pipe. Paved areas, patios or other areas without vegetative cover may be more susceptible to frost. We recommend 48 inches of soil cover over the effluent pipe and insulation with at least 2 inches of rigid foam insulation in these areas. If adequate cover soil is not possible, we should re-evaluate the condition prior to installation. • The effluent pipe should be double encased with larger diameter Schedule 40 PVC pipe underneath driveway surfaces and be provided with at least 48 inches of soil cover and be insulated on top and sides with 2 -inch -thick foam insulation board. • All 90 -degree bends should be installed using a 90 degree long -sweep or by using two 45 -degree elbows. Effluent Pumping System • An Orenco PF3005, 115 -volt, submersible effluent pump with a 1.25 -inch diameter discharge assembly, or equivalent, will be required for effluent pumping. • The maximum effluent transport distance from the pump discharge to the STA estimated to be 200 feet. • The elevation difference from pump discharge to the STA is estimated to be 4 feet. • The pump should be enclosed in an Orenco Biotube Pump Vault for effluent filtering and protection of the pump from vibration. • An equivalent pump must be capable of operating at 6.5 gallons per minute at 9.9 feet of total dynamic head. A pump performance curve is provided as an attachment to this report. • The floats should be set to provide a dose volume of approximately 102 gallons. The actual dose volume will be about 81 gallons assuming 21 gallons of drainback in the transport line. To achieve the desired dose volume, the upper ("ON") and lower ("OFF") floats should be set approximately 10 inches apart. • The flow differential between the first and last orifices is estimated to be 0.6%. Kumar & Associates, Inc. Project No. 19-7-143.02 9 • The high-water alarm float should be placed approximately 3 inches above the "ON" float in the dose tank. The high-water alarm must be wired on a separate electrical circuit from the pump. • A Y8 inch diameter weep hole should be drilled in the effluent transport line prior to exiting the dose tank so the transport line can drain after each pumping cycle. OWTS OPERATION AND MAINTENANCE The OWTS will require periodic inspection and maintenance to function properly. A properly designed, installed and maintained system can greatly increase its lifespan. The level of maintenance will vary depending on the complexity of the system and water use habits of the residents. We recommend that an OWTS Operation and Maintenance (O&M) Manual be developed. Depending on the complexity of the system, a contract with an OWTS maintenance provider may be prudent. Below are some basic recommendations for the OWTS O&M. OWTS HOUSEHOLD OPERATION • Use of high efficiency water fixtures is recommended to decrease the hydraulic load on the OWTS system. • Fix plumbing leaks immediately as this may cause a hydraulic overload of the soil absorption system. • Do not irrigate the area on top of or directly upgradient of the soil absorption field as this may cause a hydraulic overload. • Do not dispose of household waste down drains as this may clog or damage OWTS components. Examples of household waste includes: dental floss, cotton swabs, coffee grounds, paper towels, feminine products and many other kitchen and bath items. • Use of kitchen garbage disposals is not recommended. If a garbage disposal is utilized, kitchen wastewater should be screened thoroughly. Many kitchen solids are not decomposed in the septic tank and may cause increased tank pumping frequency. • Do not dispose of household chemicals, greases, oils, paints, hot tub water or water softener backwash in household drains. A separate drywell, if feasible, may be necessary Kumar & Associates, Inc. Project No. 19-7-143.02 - 10 - for hot tub water or water softener backwash disposal. • Limit the use of bleach as this may harm useful bacteria in the septic tank and soil absorption system. • Liquid dishwasher and clothes washer detergent is recommended for households served by an OWTS. Clay substances used as fillers in powder detergents may result in clogging of the soils absorption system. • The effluent in septic tanks can freeze during extended periods of non-use in cold weather. We recommend that a tank heater be installed in this system to help prevent freezing. OWTS MAINTENANCE • Inspect the septic tank, pump, pump vault filter and STA at least annually for problems or signs of failure. • The filter should be cleaned annually by spray washing solids into the first chamber of the septic tank. • The septic tank should be pumped and cleaned every 3 to 5 years depending on use. Longer pumping intervals may increase the amount of solids that reach the STA, which may shorten its life span. • Pumping of the septic tank should take place when the level of the sludge and scum layers combined take up 25 to 33% of the capacity of the first chamber of the tank. OWTS CONSTRUCTION OBSERVATION The Garfield County Building Department requires that the designer of the system provide a record drawing and certification of the OWTS construction (As -Built inspection). We should be provided with at least 48-hour notice prior to the installer needing the inspections. Prior to issuance of our certification letter, we require observation of all system components prior to backfill. The number of site visits required for the inspection will depend on the installer's construction schedule. Kumar & Associates, Inc. Project No. 19-7-143.02 -11 - LIMITATIONS We have conducted this design in accordance with generally accepted engineering principles and practices in this area at this time. We make no warranty either expressed or implied. The recommendations provided in this report are based on the site conditions, profile pit evaluations and soil texture analysis, the proposed construction and our experience in the area. 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 report, we should be notified so that 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 our design. It is our opinion that the designed location of the OWTS components does not violate any setback requirements of the current Garfield County Regulations with the exception of the sewer line which has been addresses in the design portion of this report. Below is a table of common minimum horizontal setbacks to OWTS components. Refer to the Garfield County Regulations for a complete list of required setbacks. We recommend the OWTS components be surveyed by a Professional Colorado Land Surveyor. Table 1 - Common Minimum Horizontal Setbacks from OWTS Components Kumar & Associates, Inc. Project No. 19-7-143.02 Wells Water Supply Line Occupied Dwelling Lined Ditch or Lake Lake, Irrigation Ditch, Stream Dry Ditch or Gulch Septic Tank STA 100' 25' 20' 10' 50' 25' 5' Septic Tank 50' 10' 5' 10' 50' 10' G - Building Sewer 50' 5' 0' 10' 50' 10' - Kumar & Associates, Inc. Project No. 19-7-143.02 - 12 - Please contact us for any necessary revisions or discussion after review of this report by Garfield County. If you have any questions, or if we may be of further assistance, please let us know Respectfully Submitted, Kumar & Associates, Inc. /mite - Shane M. Mello, Staff Engineer Reviewed by: David A. Young, P.E. SMM/ljf ��0,04��avee�0 6y 11 Kumar & Associates, Inc. Project No. 19-7-143.02 -TD HIGHWAY 6 25 0 25 50 SCALE -FEET C❑ LHT 9 IL6 +w 3IG R LJ 1MERCIAE 5 PARK �p II r T iu PR❑FILE PIT 3�• PROFILE PIT 4 PAVEMENT --100 FEET SETBACK TO WELL uJ w 50 FEET SETBACK TO WELL w PIT 2■ CONCRETE RAMP PR FILE ' PR FILE PIT 4 ■ PROPOSE 28' x OFFIC S❑IL TREATMENT AREA CONSISTING OF ONE ROW OF 14 INFILTRAT❑R QUICK 4 PLUS STANDARD CHAMBERS ■ -1Y6" DIA SDR -35 EFFLUENT TRANSPORT LINE /PROPOSED VALLEY PRECAST 1,000 GALLON THREE CHAMBER SEPTIC TANK WITH AN ❑RENC❑ PF3005 EFFLUENT PUMP INSTALLED IN THE THIRD CHAMBER 4" DIA SDR -35 SEWER LINE ENCASED BY 6" DIA SCH-40 PIPE 20' WELL ND 'UT�LITY ACCESS ASEMENT WELL CLEANOUT LEGEND • PROFILE PIT - PERC❑LATI❑N TEST HOLE 19-7-143.02 Kumar & Associates OWTS SITE PLAN Fig. 1 HYDROMETER ANALYSIS SIEVE ANALYSIS 24 HRS 7 HRS 45 TIME READINGS IMI 1L+ I '• U.S. STANDARD I•^ SERIES -e- CLEAR - SQUARE OPENINGS _ " " -" too too _MIN ..15.MIN_eQMIy1? _J_ 90 1 — — — 20 80_1_ _ — 70 _ _ _ I 30 6,0 - -- - — _ _ _ _ _ _ —4 40 i 50 — 50 — _ -- .. —-. _J'::. 40— — ..� _ _ 60 jj.... 30 — — 70 80 20 - - 10 90 — — } 0 .001 .002 1 1 1 1-1 1 .006 :009 .019 L 1 1 .037 .045 i I.L. 1.1.1 __ t.—J.—.1 1 d I I 1 I_:IJ_1.•1_L.L_ .108 .250 .500 1.00 2.00 4.75 0 DIAMETER OF PARTICLES IN MILLIMETERS 5 10 1 1 1 1 1 1 I.1.1...L.. 36.1 76.2 127 152 — 100 200 SILT SAND GRAVEL CLAY FINE CO. f V. FINE FINE I MEDIUM CO V CO. FINE MEDIUM I COARSE COBBLES .002 mm .02 .05 .1 .25 .5 1 2 mm 5 20 76 SAMPLE OF: LOAM FROM: PROFILE PIT 4 AT 2 TO 3 FEET ENTIRE SAMPLE GRAIN SIZE SIEVE SIZE % FINER PARTICLE SIZE DISTRIBUTION % (mm) COBBLES 0 127.00 5" 100 GRAVEL 0 76.00 3— " 100 35 i 38.10 1-1 J2" 100 _SAND SILT 43 i 19.05 3/4" 100 CLAY 22 T 9.50 3/8" 100 4.75 #4 100 2.00 10 100 1.00 #18 100 PORTION OF SAMPLE 0.50 #35 100 PASSING #10 SIEVE 0.25 #60 97 0.106 #140 84 PARTICLE SIZE DISTRIBUTION % 0.045 #325 65 SAND 35 SILT 43 GRAINSIZE (mm) TIME PASSED (min) % FINER TOTAL PERCENT PASSING CLAY SAMPLE RETAINED OF MATERIAL 3/4" SIEVE: 22 ON #10 SIEVE: RETAINED ON #10 N/A 0% SIEVE 0.037 1 59 0.019 — 4 46 0.00919 36 0.005 60 30 _ 0.002 435 22 0.001 1545 18 NOTE: Hydrometer Analysis was performed on a These test results apply only to the bulk sample following screening of all material tailing porch were teased. Ina P 9 9 Feeling report shall not be reproduced, larger than the #10 sleve (2.0 mm) per USDA except In full, without the written guidelines. approval of Kumar & Associates, Inc. Sieve analysts testing Is performed In accordance with ASTM D422, ASTM C136 and/or ASTM D1140. 19-7-143.02 Kumar & Associates USDA GRADATION TEST RESULTS Fig. 2 OWTS SOIL TREATMENT AREA CALCULATIONS In accordance with the Garfield County OWTS Regulations and the Cobrado Department of Public Health and Environment's Regulation #43, the soil treatment area was calculated as folows: CALCULATION OF OWTS DESIGN FLOW: Q = (F)(B)(N) WHERE: Q = DESIGN FLOW F = AVERAGE FLOW PER PERSON PER DAY N = NUMBER OF EMPLOYEES PROPOSED COMMERCIAL BUILDING: F= N= Q= CALCULATION OF OWTS SOIL TREATMENT AREA: MINIUMUM TREATMENT AREA = Q = LTAR WHERE: Q= LTAR (SOIL TYPE 2A) = MINIMUM SOIL TREATMENT AREA = REDUCTION FACTOR FOR CHAMBERS = REDUCTION FACTOR FOR PRESSURE DOSING TO TRENCH = MINIMUM SOIL TREATMENT AREA WITH REDUCTION = 35 GALLONS PER DAY 4 PERSONS 140 GALLONS PER DAY 140 GALLONS PER DAY 0.5 GALLONS/FP/DAY 280.0 SQUARE FEET 0.70 0.80 157 SQUARE FEET AREA PER INFILTRATOR QUICK 4 STANDARD CHAMBER = 12 SQUARE FEET TOTAL CHAMBERS NEEDED = 14 CHAMBERS NUMBER OF TRENCHES = 1 CHAMBERS PER TRENCH = 14 CHAMBERS TOTAL NUMBER OF CHAMBERS AS DESIGNED = 14 CHAMBERS TOTAL SOIL TREATMENT AREA = 168 SQUARE FEET 19-7-143.02 Kumar & Associates SOIL TREATMENT AREA CALCULATIONS Fig. 3 CLEANOUTS INSTALLED AT END OF DISTRIBUTION LATERAL. SEE FIGURE 6 FOR DETAIL 1.5' SCH. 40 PVC DISTRIBUTION PIPE WITH h" DIAMETER HOLES DRILLED AT 4 FOOT CENTERS ON TOP OF EACH PIPE. PLACE HOLES NEAR CENTER OF EACH CHAMBER. PIPE TO BE INSTALLED LEVEL AND SECURED WITH 120 LB. MIN. TENSILE STRENGTH CABLE TIES AT EACH END OF EACH CHAMBER. INFILTRATOR QUICK 4 PLUS STANDARD CHAMBERS IN ONE TRENCH. 14 CHAMBERS IN TRENCH. INSTALLED LEVEL. INFILTRATOR QUICK 4 PLUS STANDARD END CAP DRILL ONE B" DIAMETER HOLE ON THE BOTTOM OF EACH END OF DISTRIBUTION PIPE TO ALLOW FOR COMPLETE DRAINAGE. INSTALL SPLASH PLATES BENEATH DRAIN HOLES 10 0 10 20 SCALE—FEET 4 INCH DIAMETER PVC OBSERVATION PORTS INSTALLED VERTICALLY INTO KNOCKOUTS PROVIDED IN END CAPS. INSTALL VENTS AT EACH END OF EACH TRENCH. REMOVABLE LID TO BE PLACED ON TOP OF PIPE. PIPE MUST STICK UP AT LEAST 8 INCHES ABOVE FINISHED GRADE OR BE PLACED AT GRADE IN AN ACCESSIBLE VALVE BOX. PIPES SHOULD NOT EXTEND TO SOIL SURFACE AND SHOULD BE SECURED TO CHAMBER WITH SCREWS OR COUPLINGS TO PREVENT SLIDING DOWNWARD. 1.5' DIAMETER SCH. 40 SOLID PVC PIPE SLOPED AT 2% MIN. TO DRAIN BACK TO DOSE TANK Notes: 1. Chambers should be installed level on a scarified ground surface. Concrete sand may be used as a leveling course if necessary. 2. Care should be taken by the contractor to avoid compaction of the native soils in the trench areas. The base and side walls of trench excavations should be scarified prior to chamber installation. 3. Changes to this design should not be made without consultation and approval by Kumar & Associates. 4. Refer to the 2018 Garfield County Onsite Wastewater System Regulations for other applicable specifications. 19-7-143.02 Kumar & Associates SOIL TREATMENT AREA PLAN VIEW Fig. 4 Infiltrator Quick 4 Plus Standard Chamber Installed Level 12" min. 24" max. Cover Soil Graded to Deflect Surface Water Approx. Existing Ground Surface Scarify ground surface prior to chamber placement. Excavate 36" Wide Trench Notes: 1. Chambers should be installed level on a scarified ground surface. Concrete sand may be used as a leveling course if necessary. 2. Care should be taken by the contractor to avoid compaction of the native soils in nwmf the trench areas. The base and side walls of trench excavations should be 2.5 0 2.5 5 scarified prior to chamber installation. SCALE—FEET 3. Changes to this design should not be made without consultation and approval by Kumar & Associates. 19-7-143.02 Kumar & Associates SOIL TREATMENT AREA CROSS SECTION Fig. 5 Install 6" valve box at ground surface Ground Surface Backfill valve box to bottom of cap with onsite soil Insulate lid with 2" blue board 3111 APPROXIMATE SCALE: 1 INCH = 3 FEET 1.5" Sch. 40, threaded cap 1.5" Sch. 40, 90° long -sweep or two 45° elbows Notes: 1. All piping, fittings and valves should be Sch. 40 PVC. 2. Install distribution line cleanouts at the end of each distribution line. 19-7-143.02 Kumar & Associates DISTRIBUTION LINE CLEANOUT DETAIL Fig. 6 Pump Selection fora Pressurized System - Commerical Project Lot 9, Big R / Garfield County Parameters Disch ripAssertlySee 125 ids Tramp:Ma 200 Teel TraspatFipeClass 40 TrasportLneSize 150 iches DisIrbireVateMcdal Nae Na<Beam ut 4 Test MaifaldLegh 0 feet Weribld PpeClass 40 !Mitt]Pee Sze 150 iGhes Nurbaalaaatsper Cel 1 Lard Lehigh 56 Teel Lead PipeClass 40 LardFpeSze 150 aches orifceSte 1,8 fiches orifceSpacig 4 feet Radial Heal 5 feet Ron/Meer Nae ichhes Hdd•a'FricfenLasses 0 feet Calculations ftru runFbavRapper&ifce Q43 gpm NurbercfOrifcesper Zae 15 TotlFbNRdeacZcre 65 gpm Nurtacrldualsper Zane 1 %FbrvDireietfel1sN.astOrke 0.6 % Trasppt\&x l 1.0 is Frictional Head Losses Lae traxjh D ischaw 0.3 feet LcssnTraspat 05 feet Lcssfra r{�,Velee 0.0 feet LcssOD feet Loss nLatrals 0.1 feet IsestroughFbAgneer 0.0 fest 'Adi.a FriciaLosses 0.0 fed Pipe Volumes VdodTraspptLine 212 gad VddMaibid 0.0 at VdcfLairalsware 5.9 gad TdelVdure 27.1 gals Minimum Pump Requirements Desig,Flonft& 6.5 gpm TadDynsnicHeal 9.9 feet Total Dynamic Head, TDH (Feet) 300 250 200 150 100 50 4 moosi ti 00 5 10 15 20 25 Net Discharge (gpm) 30 35 40 s CO Dreammr r.r. hcormeated Clyangi elm uzid PumpData PF3005Hi HeedEI.HtPurp 30GPM, 12HP 115230) 10 03Hz203V 3060Hz