Loading...
HomeMy WebLinkAboutOWTS DesignI(t iliþilfi#nfÉtr*iÏiå*'" email An Employcc Owncd Compony 5020 County Road 154 Glenwood Springs, CO 81601 phone: (970) 945-7988 fax: (970) 945-8454 : kaglenwood@kumarusa.òom www,kumarusa.com REgÉflüË"dE: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado JAN T I 2022 GARFIELD COUNTY COMMUNITY DEVELOPMENT ONSITE \ryASTE\ryATER TREATMENT SYSTEM DESIGN PROPOSED RESIDENCE TRACT 20, ANTLERS ORCHARD 152 RUSTY SPUR TRAIL GARFIELD COUNTY, COLORADO PROJECT NO. 21-7-306 NOVEMBE,R29,202l PREPARED FOR: CHELA MURILLO P. O. BOX 885 srLT, coLoRADO 81652 @ TABLE OF CONTENTS INTRODUCTION. PROPOSED CONSTRUCTION SITE CONDITIONS OWTS OPERATION AND MAINTENANCE...... OWTS HOUSEHOLD OPERATION OWTS MAINTENANCE....... OWTS CONSTRUCTION OBSERVATION LIMITATIONS FIGURES FIGURE 1 _ OWTS SITE PLAN FIGURES 2A ANd 2B _ USDA GRADATION TEST RESULTS FIGURE 3 _ SOIL TREATMENT AREA CALCULATIONS FIGURE 4 _ SOIL TREATMENT AREA PLAN VIEV/ FIGURE 5 _ SOIL TREATMENT AREA CROSS SECTION ATTACHMENTS VALLEY PRECAST 1,500 GALLON, TV/O-CHAMBER SEPTIC TANK DETAIL TUF-TITE 4-HOLE DISTRIBUTION BOX I I I SUBSURFACE CONDITIONS .......- 1 . OWTS ANALYSIS ..-2- DESIGN RECOMMENDATIONS ............... SOIL TREATMENT AREA OWTS COMPONENTS aJ J 4 -7 - -7 - 8- 8- -8- Kumar & Associates, lnc.ProJect No.2l-7-306 INTRODUCTION This report provides the results of an onsite wastewater treatment system (OWTS) design for the proposed residence to be located on Tract 20, Antlers Orchard, 152 Rusty Spur Trail, Garfield County, Colorado. The purpose of the report is to provide design details for the OWTS in accordance with the Garfield County Environmental Health Department Onsite'Wastewater Treatment System Regulations and the Colorado Department of Public Health and Environmental Regulation#A3. The services are supplemental to our agreement for professional services to Chela Murillo dated March 29,2021. PROPOSED CONSTRUCTION The residence will be a three-bedroom single-family structure located on the lot as shown on Figure 1. The OWTS will be designed for a total of five bedrooms to allow for future expansion. The proposed soil treatment area (STA) for the OWTS will be located to the south of the residence as shown on Figure 1. V/ater service will be provided by an onsite well. The location of the well and route of the water supply line to the residence has not been designed at the time of this report. If proposed construction is different than that described, we should be contacted to re-evaluate our design recommendations. SITE CONDITIONS The site was vacant at the time of our field exploration. An access road had been graded into the building site. The terrain at proposed building area slopes down to the south at l0 to 15 percent grade. Vegetation consists of grass and weeds with sagebrush, and alarge cottonwood tree to east of building area. Sandstone/siltstone bedrock outcrops to the southwest of building site. SUBSURFACE CONDITIONS The field exploration for the OWTS was conducted on April 1, 2021. Two profile pits (Profile Pits 1 and2) were dug with a mini-excavator atthe approximate locations shown on Figure 1 to evaluate the subsurface conditions at the planned soil treatment area for the OWTS. The pits were logged by a representative of Kumar & Associates. Logs of the profile pits are provided below. Kumar & A¡¡oclates, lnc.ProJect N0.21'7.306 Depth USDA Classification 0-1'TOPSOL; organic Loam, firm, slightly moist, brown. 1 )5 ,SANDY LOAM; moderate blocky structure, very stifÏ, slightly moist, brown. 5 )7',WEATHERED CLAYSTONE BEDROCK; hard, slightly moist, gray o o a Disturbed bulk sample obtqinedfrom 2 to 4 feet. Bottom of pit @ 7 feet. No groundwater or redoximorphic.features observed at time of pit excavation n Log of Profile Pit I Log of Profïle Pit 2 The soils encountered in profile pits, below about 1 foot of organic topsoil, consisted of Sandy Loam down to the pit depth of 8 feet at Profile Pit2. Af Prof,rle Pit l, the Sandy Loam was underlain by weathered claystone bedrock at a depth of 5 feet. Hydrometer and gradation analyses were performed on a disturbed bulk sample of the soils from Profile Pit 1 from 2 to 4 feet depth and Profile Pit 2 from l%to 3Yz feet depth with the results provided on Figures 2A and2B., respectively. The tested samples (minus No.10 size sieve fraction) classiff as Sandy Loam per the USDA system. No free water was encountered in the pits nor indications of seasonal high groundwater were observed at the time of the pit excavations. Based on the subsurface conditions and laboratory testing, the soils at the STA have been classified as Type 2 per State regulations, which equates to a long-term acceptance rate (LTAR) of 0.60 gallons per square foot per day. OWTS ANALYSIS Based on the site conditions and profile pit evaluations, the evaluated area should be suitable for a conventional infiltration disposal system. There is adequate elevation difference from the proposed ground floor of the residence down to the STA for gravity flow of the sewer effluent. The STA will consist of chambers in a trench configuration based in the Sandy Loam soils. The STA will be sized fbr five bedrooms (eight persons) and an average daily flow of 75 gallons per person, and an LTAR of 0.60 gallons per square foot per day for the natural Sandy Loam soils. Depth USDA Classification 0-1'TOPSOIL; organic Loam, firm, moist to slightly moist, dark brown. 1'-8',SANDY LOAM; moderate blocky structure, very stiff, slightly moist, brown. a a a Disturbed bulk sample obtqined from I % to 3 % feet Bottom of pit @ I feet. No groundwater or redoximorphic.features observed at time of pit excavqtion Kumar & Assoclates, lnc.ProJect No. 21-7.300 -5- The effluent will gravity flow from the residence to the septic tank for primary treatment and then gravity flow to the STA for dispersal and final treatment. The STA will consist of three trenches with Infiltrator Quick 4 Plus Standard chambers. Equal distribution will be provided to the chambers and trenches by a distribution box. Due to the presence of relatively shallow bedrock at Profile Pit2, an additional profile pit should be excavated at the time of construction near the eastern end of the STA to veri$ the required 4 feet ofsoil separation from the bottom ofthe trenches to the bedrock surface. The location of the onsite well and the route of the planned water supply line to the residence are currently not known. The setback of the well from the septic tank, effluent lines, and sewer lines is 50 feet. The setback of the well from the STA is 100 feet. The required setback of the water line from the septic tank is l0 feet, 5 feet for sewer and effluent lines, and 25 feef from the STA. We should be notified for additional recommendations if these setbacks cannot be met. 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 OV/TS components is provided on Figure 1. If conditions encountered during construction are different than those that are described in this report, we should be contacted to re-evaluate our design recommendations. SOIL TREATMENT AREA . The STA will consist of three trenches with 20 Infiltrator Quick 4 Plus Standard chambers placed in each trench (60 chambers total) in the native soils. Equal distribution will be provided to the trenches by a distribution box. o The STA was sized based on an LTAR of 0.60 gallons per square feet per day. o Each chamber was allowed 12 square feet of area . A 30% reduction of the STA size was applied for use of Infiltrator chambers in a trench configuration. The total STA design size is 720 squarc feet. Soil treatment area calculations are shown on Figure 3. o A minimum of four feet of undisturbed soil between trenches is required. o Trench cut depths should be a maximum of 2 feet below existing ground surface. o The trenches should be oriented along ground contours to minimize soil cut and cover. o The base and sidewalls of the trench excavations should be scarified prior to the chamber placement. o A minimum of 12 inches and a maximum of 24 inches of cover soil should be placed over the chambers. Kumar & A¡¡oclates, lnc.ProJgct No,21.7.306 -4- . Backfill should be graded to deflect surface water away from the STA and should be sloped at 3 horizontal to 1 vertical or flatter. A swale to divert surface water flow away from the STA may be needed along the upslope side. o 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. o Four-inch diameter inspection ports should be installed vertically into the knockouts provided in the chamber end caps. Install ports at eaih end of the trench. The inspection port piping should be screwed into the top to the chambers and should not extend down to the ground surface inside the chambers. The inspection ports should extend at least I inches above the finished ground surface or be protected in a valve box at finished grade. o The STA must be a minimum of 100 feet from any well. o The STA must be a minimum of 50 feet from any inigation ditch or stream. o The STA must be a minimum of 5 feet from the septic tank. o The STA must be a minimum of 25 feet from any potable water supply lines. o The STA must be a minimum of 20 feet from the residence. o A plan view of the STA is presented on Figure 4 and a cross section of the STA is presented on Figure 5. 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 o A Valley Precast 1,500 gallon, two-chamber septic tank should be used for primary treatment and dosing to the STA. A detail of the tank is provided as an attachment. o An effluent filter should be installed in the tank outlet tee. o The septic tank must be a minimum of 50 feet from any well. o The tank must be a minimum of 5 feet from the residence. o The tank must be a minimum of 10 feet from any potable water supply lines. o 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. Kumar & Assoclates, lnc.ProJoct No,21.7-306 -5- o The tank lids must extend to final surface grade and made to be easily located. o Install the tank with2 feet minimum cover soil for frost protection. Maximum tank soil cover is 4 feet. Sewer Pipe o 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. o The sewer pipe should have a rating of SDR35 or stronger. Schedule 40 PVC pipe is required beneath any driveway surfaces. o The sewer pipe should be sloped between 2%o to 4Yo 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 venical step-downs in the sewer line. o A minimum 24 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. o The sewer pipe should be bedded in compacted%-inch road base or native soils provided that the native soils contain no angular rocks or rocks larger than2% inches in diameter to help prevent settlement of the pipe. Sags in the pipe could cause standing effluent to freeze and damage the piping. o Install cleanout pipes within 5 feet of the building foundation, where the sewer pipe bends 90 degrees or more and every 100 feet of sewer pipe. o All 9O-degree bends should be installed using a 9O-degree long-sweep or by using two 45-degree elbows. o The sewer line location shown on Figure 1 is considered conceptual. We assume that there will be only one sewer line exiting the residence. 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 o The effluent transport pipe should be 4-inch diameter SDR35 piping sloped at a2o/o minimum to flow from the septic tank to the distribution box and from the distribution box to each trench. Piping should extend at least 6 inches into the top knockout provided in the Infiltrator end caps and be screwed in place. Splash plates should be installed Kumar & A¡¡oclate¡, lnc.Prolect No.21.7.306 -6- a a a beneath the inlet piping to help limit scouring of the infiltrative soil surface in the chambers. The effluent transport pipe should be bedded in compacted3/o-inch road base or native soils provided that the native soils contain no angular rocks or rocks larger than 2Yz 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 least2 inches of rigid foam insulation in these areas. If adequate cover soil is not possible, we should re-evaluate the condition prior to installation. Schedule 40 PVC pipe is required underneath driveway surfaces and should be provided with at least 48 inches of soil cover, and be insulated on top and sides with 2-inch thick rigid foam insulation board. All 90-degree bends should be installed using a 90 degree long-sweep or by using two 45-degree elbows. Distribution Box o The distribution box will be used to equally divide effluent flow between the trenches. We recommend the Tuf-Tite 4-Hole Distribution Box since it is easily accessible from ground surface for maintenance. A copy of the distribution box detail is provided as an attachment to this report. o The distribution box outlet pipes should be equipped with Tuf-Tite speed levelers for ease of initial setup and adjustment over time. o The distribution box should be a minimum of 18 inches below grade with risers and an access lid at or above grade. o The distribution box must be accessible from ground surface for inspection and maintenance per the State guidelines. o The effluent line from the septic tank should be directed downward into the distribution box with a 9O-degree elbow inside the box. o The distribution box must be installed level on a compacted road base subgrade to ensure equal effluent distribution. If settlement of the distribution box occurs, unequal effluent distribution may take place which could cause hydraulic overload of one of the trenches and potential failure. The distribution box should be monitored periodically, and the speed levelers should be adjusted as necessary for levelling. Kumar & A¡soclatea, lnc.ProJect No.21-7.306 -7 - The ground surface above and around the distribution box should be graded to drain away surface water to prevent standing water near the distribution box which could freeze or cause settlement. 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 o Use of high efficiency water fixtures is recommended to decrease the hydraulic load on the OWTS system. o Fix plumbing leaks immediately as this may cause a hydraulic overload of the soil absorption system. r Do not irrigate the area on top of or directly upgradient of the soil absorption field as this may cause a hydraulic overload. o Do not dispose of household waste down drains as this may clog or damage OV/TS components. Examples of household waste includes: dental floss, cotton swabs, coffee grounds, paper towels, feminine products and many other kitchen and bath items. o 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. o 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 for hot tub water or water softener backwash disposal. o Limit the use of bleach as this may harm useful bacteria in the septic tank and soil absorption system. o Liquid dishwasher and clothes washer detergent is recommended for households served by an OWTS. Clay substances used as flrllers in powder detergents may result in clogging of the soils absorption system. o 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. Kumar & As¡oclatel, lnc.ProJect No, 21.7.306 -8- OWTS MAINTENANCE . Inspect the septic tank, distribution box and STA at least annually for problems or signs of failure. o The effluent filter for the tank should be cleaned at least annually by spray washing solids into the first chamber of the septic tank. o 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. o Pumping of the septic tank should take place when the level of the sludge and scum layers combined take up 25 to 33o/o of the capacity of the first chamber of the tank. OWTS CONSTRUCTION OBSERVATION The Garfield County Environmental Health 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. LIMITATIONS We have conducted this design in accordance with generally accepted engineering principles and practices in this area at this time. We make no rúarranty 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 pulposes. 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 veriÛ' that the recommendations have been appropriately interpreted. Significant design changes may require additional analysis or modifications to our design. Kumar & As¡oclates, lnc.ProJect No,21.7.306 -9 - It is our opinion that the designed location of the OrülTS components does not violate any setback requirements of the current Garfield County Regulations. Below is a table of common minimum horizontal setbacks to OV/TS components. Refer to the Garfield County Regulations for a complete list of required setbacks. Vy'e recommend the O\MTS components be surveyed by a Professional Colorado Land Surveyor. Table 1 - Common Minimum Horizontal Setbacks from OWTS 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. :Ø**WÞ Shane M. Mello, Staff Engineer Reviewed by: David A. Young, SMMlkac Dry Ditch or Gulch Septic Tank\ilells Water Supply Line Occupied þ¡¡'slling Lined Ditch Lake, Irrigation Ditch, Stream 25',5'25',20'10'50'100''STA 10'50'10'50'10',5Septic Tank 50'10'50',5 0'10'Building Sewer Kumar & Associates, lnc.Project No. 21-7-306 RUSTY SPUR TRAIL \RACI t"tÊ 4 TAA FEûE rcf&IE PANT PßT@mvErAr t&Í IEICE eræf AN,E PAN| ü! ïËs a7 T (t É Ê7ftm PN M,tr sET ton oütw ñ-ttd -o-- x <i. CLEANOUT \ ttî -tooo FE {cE Fær PROPOSED -1 VALLEY PRECAST 1,500 GALLON TWO CHAMBER SEPTIC TANK TUFTITE 4-HOLE ¿' *1 t\ DISTRIBUTION BOX \ :RÈ ,rororro róii\\\ TREATMENT AREA (srA) r ROWS \coNstsÏNc oF 3 -/\OF 20 INFILTRATOR QUICK4 PLUS STANDARD CHAMBERS, (60 CHAMBERS TOTAL) * pRon LE.ì PROFILE .-- PIT 2 \ PITl \\-\\ E */OE OE æ- ú ..Po'/ { 4 ù ,.d 020 SCALE-FEET PROPOSED 3_BEDROOM RESIDENCE 152 RUSTY SPUR TRAIL "- ->l )rr(I I I Fig. 1OWTS SITE PLAN21 -7 -306 Kumar & Associates 2 ø too eo 80 70 EO lo 11) 30 20 to o o to 20 30 /ao 50 50 70 80 90 roo - u R IN MILLIMETERS CLAY COBBLES ,002 mm .02 '05 SAMPLE OF: SANDY LOAM .25 ,5 I Zmm 5 20 FROM: PROFILE PIT 1 AT 2 T0 4 FEET ENTIRE SAMPLE PARTICLE SIZE DISTRIBUTION % COBBLES 0 GRAVEL 2 SAND 72 SILI 15 CLAY t3 PORTION OF SAMPLE PASSING #10 SIEVE PARTICLE SIZE DISTRIBUTION % SAND 73 SILT 13 CLAY 11 TOTAL SAMPLE RETAINED ON f10 SIEVE: 2% PERCENT OF MATERIAL RETAINED ON #10 SIEVE PASSTNG 5/4" S|EVE: 1OO% NOTE: Hydrometer Anolysis wos Performod on o bulk somplo followlng screenlng of oll molerlol lorger lhon the ¡f10 sieve (2.0 mm) per USDA guldelines. fhca! llrl rosull! qpply only lo lhr eqmpl.s whlch w!rc tlsl¡d. lhr hlllng rcport sholl nol ba rcproduced, oxcapl ln tull, wllhout lho wrlllsnqpproyol of Kumqr & A9goclql.s, lnc, Siovr onolysl! losllng lt pcrformad ln occordonca wlth ASTM 0,122, ASTM C135qnd/or ASTM Dtt40. SIEVE ANALYSISHYDROMETER ANALYSIS lIME READINCS IMll2,4 HRS 7 HRS CLËAR SQUARE OPENINOSU,S. SIANDARD SERIES GRAVELSANDSILT COARSEV. FINE FINE MEDIUM co.v. co.FINE MEDIUMFINEco. GRAIN SIZE (mm)SIEVE SIZE % FINER 127.00 100 78.00 100 38.1 0 1-1 /2"f00 19.05 3/4 100 9.50 3/8"100 1.75 #1 99 2.OO #10 9E 1.00 #18 97 0.50 #35 91 0.25 #60 7A 0.1 06 +1 10 17 0.045 #525 26 GRAIN SIZE ('n-) TIME PASSED (mln)% FINER 0.037 25 0.019 4 23 0,009 19 19 0,005 60 l9 0.002 455 15 0.001 15¡t5 11 21 -7 -306 Kumar & Associates USDA GRADATION TTST RTSULTS Fig.2A n , H too 90 80 70 80 30 10 30 20 to o to 20 50 ao 50 00 70 ao 00 too = H E Ë R OF PARTIC CLAY COBBLES ,02 ,05 .1 ,5 1 2mm 5 20 76 SAMPLE OF: SANDY LOAM FROM: PROFILE PIT 2 AT 1'1/2 10 3-1/2 IEET ENTIRE SAMPLE PARTICLE SIZE DISTRIBUTION % COBBLES 0 GRAVEL 3 SAND 68 SILT 't6 CLAY 15 PORTION OF SAMPLE PASSING #10 SIEVE PARTICLE SIZE DISTRIBUTION % SAND 70 SILT 17 CLAY l3 TOTAL SAMPLE RETAINED ON jl10 SIEVE: 3% PERCENT OF MATERIAL RETAINED ON #10 SIEVE PASSTNG 5/4" SIEVET 1OO% NOTE: Hydromeler Anolysls wos performed on o bulk somple following screenlng of oll moterlol lorger lhon the f10 sleve (2.0 mm) per USDA guldellnes, Thrsr losl rosull3 opply only lo lhr sqmpbs whlch w.ro llshd, Thc lorllng r.Þort lholl nol br rlproducod, axcopl ln full, wllhoul lhe wrlllsn qÞÞrgvql gl Kumor & Arloclqttt, lnc' Siovo onolycl¡ hlllng l! p€rtormrd ln qcçordonco wlth ASTM 0,122, ASIM C136qnd,/or ASTM Dlt,lo. HYDROMETER ANALYSIS SIEVE ANALYSIS IIME READINOS l MIN2,4 HRS 7 HRS U,S. STANDARD SERIES ¡t¡ CLÊAR SQUARE OPENINGS !/^. !tl. I ttr. SAND GRAVELSILT FINE MEDIUM co.v. co.FINE MEDIUM COARSEFINEæ.V, FINE GRÀIN SIZE (m'n)SIEVE SIZE % FINER 127.0O 100 76.00 100 58.1 0 1-1 /2"100 19.05 3/4"100 9,50 3/8"f00 4.75 *4 99 2.00 #10 97 1.00 #18 96 0.50 #35 91 0,25 #60 66 0.1 06 t|l 10 56 0.0¡t5 *325 29 GRAIN SIZE(-'n)TIME PASSED (mln)% FINER 0.037 29 0.019 1 21 0.009 19 20 0.005 60 l8 0.002 455 15 0.001 t 545 13 21 -7 -306 Kumar & Associates USDA GRADATION TEST RESULTS Fis.2B OWTS SOIL TREATMENT AREA CALCULATIONS In accordance wtlh the Garfeld County OWTS Regulations and the Colorado Depatment of Publb Health and Environment's Regulation #43, the soiltreatment area was cabulated as follows: CALCULATION OF OWTS DESIGN FLOW: q = (F)(N) N = 2 PERSONS PER BEDROOM FOR FIRST 3 BEDROOMS AND 1 PERSON PER BEDROOM FOR EACH ADDITIONAL BEDROOM WHERE: Q = DESIGN FLOW F = AVERAGE FLOW PER PERSON PER DAY B = NUMBEROF BEDROOMS N = NUMBER OF PERSONS þ= $= N= Q= 75 GALLONS PER DAY 5 BEDROOMS 8 PERSONS 600 GALLONS PERDAY CALCULATION OF OWTS SOIL TREATMENT AREA: MINIUMUM TREATMENT AREA = Q + LTAR WHERE: Q= LTAR (SOIL TYPE 2) = 600 GALLONS PER DAY 0.6 GALLONS/FTTDAY MINIMUM SOIL TREATMENTAREA =1000.0 SQUARE FEET REDUCTION FACTOR FOR CHAMBERS =0.70 MINIMUM SOIL TREATMENTAREA WITH REDUCTION = 7OO SQUARE FEET AREA PER INFIHRATOR QUICK 4 STANDARD CHAMBER = TOTAL CHAMBERS NEEDED = 12 SQUARE FEET 59 CHAMBERS NUMBER OF TRENCHES = CHAMBERS PERTRENCH = TOTAL NUMBER OF CHAMBERS AS DESIGNED = 3 TRENCHES 20 CHAMBERS 60 CHAMBERS TOTAL SOIL TREATMENTAREA =720 SQUARE FEET 21-7-306 Kumar & Associates SOIL TREATMENT AREA CALCULATIONS Fis. 3 4 INCH DIAMETER NON-PERFORATED SDR55 TRANSPORT PIPE SLOPED AT A 2% MIN. DOWN TO DISTRIBUTION BOX. 4 INCH DIAMETER NON-PERFORATED SDR35 TRANSPORT PIPE SLOPED AT A 2% MIN. DOWN TO TRENCH. TUF_TITE 6_HOLE DISTRIBUTION BOX INFILTRATOR QUICK4 PLUS STANDARD CHAMBERS IN 3 TRENCHES. 20 CHAMBERS PER TRENCH (60 TOTAL). TRANSPORT PIPING SHOULD BE INSERTED AT LEAST 6 INCHES INTO THE UPPER KNOCKOUT IN THE END CAP. INSTALL SPLAS INFILTRATOR QUICK4 PLUS STANDARD END CAP. PLATES BENEATH INLET PIPING TO HELP LIMIT SCOURING OF THE INFILTRATIVE SURFACE. 4 INCH DIAMETER PVC OBSERVATION PORTS INSTALLED VERTICALLY INTO THE KNOCKOUTS PROVIDED IN END CAPS, INSTALL PORTS 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 10 0 SCALE- FEET Notes: .l . 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. All piping should have a rating of SDR35 or stronger. 4. Changes to this design should not be made without consultation and approval by Kumar & Associates. S. Refer to the 2018 Gafield County Onsite Wastewater System Regulations for other applicable specifications. 21 -7 -306 Kumar & Associates SOIL TRTATMENT AREA PLAN VIEW Fig. 4 Native Soil Trenche Soil Between lnfiltrator Quick 4 Plus Standard Chamber Excavate 36" Wide Trench '12" min. 24" max. Cover Soil Graded to Deflect Surface Water lnstalled Level Approx.Existing Ground Surface Scarify ground surface prior to chamber placement. 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. 2.5 SCALE- FEET 21 -7 -306 Kumar & Associates SOIL TREATMENT AREA CROSS SECTION Fig. 5 íSOO Gallon Top Seam -2CPItem # l500T.2GP DESIGN NOTES¡ Design per performonce test per ASTM c|227r Top surfoce oreo 62.55 ft'¿¡ f'c @ 28 doys; concrete = 6,000 PSI Min. ln stollotion:¡ Tonk to be set on 5" min. sond bed or peo grovel¡ Tonk to be bockfilled uniformly on oll sides in lifts less thon 24" ond mechonicolly compocted¡ Excovoted moteriol moy be used for bockfill, provided lorge stones ore removedo Excovotion should be dewotered ond tonk filled with woter prior to being put in service for instollotíon with woter toble less thon 2' below grode¡ Meets C1644-06 for resilient connectors¡ lnlet ond Outlet identified obove pipe¡ Delivered complete with internol piping ¡ 4' Moximum bury depth ,-Eè'.ir Top View l- J 2üOearAccæs i i¡*r lLrD j [l :-..-:?1.J.t Rlsers b Gnade Boot Rubber Sealant 6i 3n 5i ]n Section View . Disgine Sngcs 13' Long x I' Wide 56" below inlet lnvert Dimensions Net Copocity Net Weíght lnlet 0ullet Length width Height lnlet Side Outlet Totol Lid Tonk Totol 56"53"132"68"68"1002 gol 507 gol 1509 gol 3600 lbs 11180 lbs 14780 lbs ALLOWABLE BURY (Bosed on Woter Toble) WAÏER TABLE ALLOWABLE FARTH FILL 0'- 0"3'- 0" 1'- 0"3'-0" 2'-O"4'-O" 3'-O"4'-O" DRY 4'- 0" Phone: 719€956764 Fax 7l$39æ7n Webelb: www.valleypr€castæm Emal | : fionHesk@val le¡precasùoomBuena Vlsta, Colorado PRECAST,Inc. Tough Providing Problem a simple, reliable, and - permanent means for dividing septic tank effluent flow. TUF-TITE Solution A strong, stable, permanent, non-corrosive Tuf-Tite Distribution Box, with a Tuf-Tite Speed Leveler in each outlet, I lnjection molded HDPE I Non-corrosive f Simple to install I Easy to level ln a septic environment, no other materialcan match High Density Polyethylene in delivering a lifetime of trouble-free service. Tuf-Tite Distribution Boxes are injection molded, using only premium HDPE which contains no fillers or foam. Snap-in pipe seals They're patented. Simply insert your PVC pipe and push it through the flexible, polyethylene Tuf-Tite seal. Pipes fit watertight. lnstallation couldn't be easier. They're permanent Unlike cement-based pipe grout, TuËTite seals will not crack or corrode in septic conditions. They stay pliable and watertight permanently. TU THole I lnjection molded. Exceptionally 11" 2" Drop S-35 '/l¡s-40 P-10 Choice of Fittings S-35 Pipe Seal, for: t Sewer and Drain r SDR 35 T ASTM 3034 r Thin Wall r 1500 Lb. Crush S-40 Pipe Seal, for: I Schedule 40 I 4" Corrugated P-10 Plug, for unused holes strong, Choice of Lids Regular Lid. Molded of rugged HDPE. lnspection Pod Lid, For easy access and inspection. Models available to accept either 4" or 6" extension pipes. Interlocking Lid. Heavy-duty HDPE Lid is ribbed for added strength and rigidity. Slotted sides interlock on the Distribution Box to assure a tight fit. The 4HD2 Distribution Box comes complete with a Regular Lid or an lnspection Port Lid, and 5 snap-in fittings of your choice. Model 81 Riser. For series 81 Box. Stackable HDPE Risers extend to grade in 6" increments. Accept 11" x 11" lids and grates. Tuf-Tite Speed LevelersTM Control the flow of effluent from the Distribution Box. Simply insert a Speed Leveler into each outlet pipe. Rotate each Speed Leveler so the flow is distributed as desired, Available for 3" or 4" PVC pipe. t HDPE is non- corros¡ve in a septic env¡ronment. 1sVi', 11" I Patented snap-¡n p¡pe seals simplify installation. INSTALLATION IS JUST THIS SIMPLE 1. Position the Distribution Box on level virgin soil, Do not place box on a concrete slab. 2. lnstallthe inlet pipe and outlet pipes. Be sure the bottoms of all pipes rest on virgin soil. 3. Levelthe Distribution Box and all pipes as needed. 4. Backfill the pipes to within two feet of the Distribution Box. Recheck the level of the box, then backfill up to the top lid ridge. 5. lnstall and adjust Tuf-Tite Speed Levelers. 6. Place lid on the Distribution Box and finish backfilling. '1 6" .;1,îr"TUt'TITE'il t Drainage and Septic Products Tuf-Tite' Corporation 1200 Flex Court Lake Zurich, lllinois 60047 O1 999 Tuf -Tite@ Corporation * f A lull line of innovations for befter sepfic systerns Form 4HD2'3. Pr¡nled in USA