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Home My WebLink AboutOWTS Design Packet - UPDATES 09.24.2020CBO.I til?1"1'I(' ('( )\tii'I:PI\(: August 20, 2020 33 FOUR WHEEL DRIVE ROAD CARBONDALE, CO 81 623 970.309.5259 CARLA.OSTBERG@GMAI L. COM Kurt Carruth kurt@hinge-architects.com Subsurface Investigation and Onsite Wastewater Treatment System Design Metal Shop 160 Gemat Circle Lot 4, Big R Commercial Park Garfield County, Colorado Kurt, Project No. C1534 CBO Inc. performed a subsurface investigation and completed an onsite wastewater treatment system (OWTS) design for the subject residence. The 2.0-acre property is located outside of Rifle, in an area where OWTSs are necessary. Legal Description: Section: 11 Township: 6 Range: 93 Subdivision: BIG R COMMERCIAL PARK Lot: 4 2 ACRES Parcel ID: 2177-111-03-004 SITE CONDITIONS The parcel is located in a commercial park and is undeveloped. The intended use of the proposed building is a metal shop. The building will be served potable water from a private well on the property. The well was not drilled at the time of this design. The well will not come within 50-feet of the proposed septic tank and within 100- feet of the proposed soil treatment area (STA). No OWTS component will come within 25-feet of the existing water line. No OWTS component may come within 25-feet of stormwater drainage infrastructure, including any that may be installed on neighboring properties. The proposed STA location is relatively flat and is located to the west of the proposed structure. There should be no traffic or staging of material over the future STA site to avoid compaction of soils prior to construction of the STA. SUBSURFACE The subsurface was investigated on June 16, 2020 by digging two soil profile test pit excavations (Test Pits). A visual and tactile soil analysis was completed by Carla Ostberg.1 ' Carla Ostberg holds a Certificate of Attendance and Examination from the CPOW Visual and Tactile Evaluation of Soils Training. Page 2 The materials encountered in the Test Pit #1 consisted of light sandy loam with moderate structure grade to 5.0-feet, underlain by light brown sandy loam with weak structure grade to a maximum depth explored of 8.0-feet. No bedrock or groundwater was encountered. Soils in Test Pit #2 were similar to those encountered in Test Pit #1. The test pit was excavated to a maximum depth explored of 8.0-feet. No bedrock or groundwater was encountered. A sample of the soils was taken from Test Pit #1 at 3-feet below grade. Soil structure grade was moderate. The soil formed a ball and a ribbon less than 1-inch in length before breaking. Soil structure shape was blocky and consistence was friable to firm. Soil texture was more gritty than smooth. STA sizing is based on Soil Type 2A, Sandy Loam with weak structure grade below 5-feet. A long term acceptance rate (LTAR) of 0.5 gallons per square foot will be used to design the OWTS. Test Pit #1 Page 3 View of site backfill Test Pit #2 Page 4 Sieved sample ribbon less than 1" DESIGN SPECIFICATIONS Design Calculations: Average Design Flow = 15 GPD x 4 office employees = 60 GPD Design Flow = 150 GPD (estimated high) LTAR = 0.5 GPD/SF 150 GPD / 0.5 GPD/SF x 1.0 (gravity trenches) x 0.7 (chambers) = 210 SF Four employees are anticipated at the Metal Shop. Fixtures include a toilet/lavatory and shop sink. The OWTS design is based on an average daily wastewater flow of 150 GPD. The OWTS was designed to handle domestic waste only. Floor drains should be routed to a separate drywell. For the purposes of this OWTS design, Benchmark Elevation has been established as 100' as the sewer line exiting the shop. CBO Inc. should be notified of any discrepancies or problems with grade elevations of proposed components during installation of the OWTS. OWTS Component Minimum Elevation Primary Tank Inlet Invert Approx. horizontal distance 22' / min. 2% fall / min. 5.5" fall Distribution Box Approx. horizontal distance 176' / min. 1% fall / min. 22" fall Infiltrative Surface Approx. horizontal distance 10' to nearest trench / min. 1% fall / min. 1.25" fall The sewer line exiting the residence must have a double -sweep clean out and a minimum 2% grade to the septic tank. We recommend Schedule 40 sewer line and tracer wire to be installed under all areas subject to traffic. The system installation must include a 1000-gallon, two -compartment concrete septic tank with an effluent filter on the outlet tee. Risers must bring the manhole lids to grade for access. If more than one riser is added to the septic tank, an extension handle must be installed on the effluent filter. If the septic tank will be located in an area subject to traffic, a traffic -rated septic tank must be installed, along with traffic rated risers and cast iron lids. Effluent will gravity flow to a distribution box, and then to two gravelless chamber trenches. An additional double -sweep clean out must be installed on the sewer line leading to the distribution box as the distance Page 5 exceeds 100-feet. The distribution box must be accessible from grade and must have flow equalizers, or similar product, installed on each outlet pipe in the distribution box to assure equal flow to each bed. Each trench will consist of 9 `Quick 4' Standard Plus Infiltrator® chambers for a total of 18 chambers and 216 square feet of infiltrative area. There must be at least 4-feet of undisturbed soil between each trench. Installation of trenches should be as shallow as possible with a minimum 1-foot of cover and maximum 3-feet of cover over chambers. Attention must be paid to maintaining minimum fall for sewer pipes while trying to maintain shallow installation of trenches. Inspection ports must be installed at the beginning and end of each trench. Ports may be cut to grade and placed in sprinkler boxes for access. COMPONENT SPECIFICATIONS The component manufacturers are typical of applications used by contractors and engineers in this area. CBO Inc. must approve alternative components prior to installation of the OWTS. Requests must be submitted, in writing, to our office for approval prior to installation. Component technical data sheets are available upon request. Please contact this office for traffic -rated options, if needed. COMPONENT MANUFACTURER MODEL NO. COMMENTS Septic Tank Valley Precast IM-1000-2CP 1000-gallon, 2- compartment concrete septic tank Biotube Effluent Filter Orenco® Full Size Effluent Filter and housing Tank Risers and Lids Orenco® Double -walled PVC Risers and Lids (24" diameter) Distribution Box Polylok UD-Box 6 poly distribution box, risers, lid Flow Equalizers Polylok RotoFlow 4" 4 Flow Equalizers Chambers Infiltrator® Low Profile 18 `Quick 4' Low Profile Chambers 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 On -Site Wastewater Treatment System Regulations, the OWTS Permit provided by Garfield County Building Department, and this design. INSTALLATION CONTRACTOR CBO Inc. expects that the installer be experienced and qualified to perform the scope of work outlined in this design. The installer must review this design thoroughly and coordinate with our office in advance of installation. Any additional conditions in this design or county permit must be completed and documented prior to final approval of the OWTS installation. Communication between the installer and this office is expected throughout the installation. INSTALLATION OBSERVATIONS CBO Inc. 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. CBO Inc. should be notified 48 hours in advance to observe the installation. In an effort to improve the accuracy of the record drawing, we request that the installer provide a sketch of the installation, including path of the sewer lines, water line installation (if applicable), Page 6 septic tank location, STA location, and measurements from building corners or another fixed objects on the property. This sketch is most easily provided on Sheet W2.0 of the OWTS Design Packet. Photographs of the installation and final cover are also requested to supplement our installation documentation. REVEGETATION REQUIREMENTS An adequate layer of good quality topsoil capable of supporting revegetation shall be placed over the entire disturbed area 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 irrigation shall be placed over the STA. 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 STAs, and any other components needing maintenance. Geo-fabrics or plastics should not be used over the STA. No heavy equipment, machinery, or materials should be placed on the backfilled STA. Machines with tracks (not wheels) should be used during construction of the STA for better weight distribution. Livestock should not graze on the STA. 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 a STA. If an effluent filter or screen has been installed in the OWTS, we recommend this filter or screen be cleaned annually, or as needed. If the OWTS consists of a pressurized pump system, we recommend the laterals be flushed annually, or as needed. 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, weep holes must be installed to allow pump lines to drain to minimize risk of freezing. The pump shall have an audible and visual alarm notification in the event of excessively high water conditions and shall be connected to a control breaker separate from the high water alarm breaker and from any other control system circuits. The pump system shall have a switch so the pump can be manually operated. Excavation equipment must not drive in excavation of the STA 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 the STA must be uniform and granular with no material greater than minus 3-inch. Page 7 LIMITS: The design is based on information submitted. If soil conditions encountered are different from conditions described in report, CBO Inc. should be notified. All OWTS construction must be according to the county regulations. Requirements not specified in this report must follow applicable county regulations. The contractor should have documented and demonstrated knowledge of the requirements and regulations of the county in which they are working. Licensing of Systems Contractors may be required by county regulation. Please call with questions. Sincerely, CBO Inc. Ow, Co_ C'ErhbAs Reviewed By: Carla Ostberg, MPH, REHS Romeo A. Baylosis, PE NI 43S11 39 1Sf11/\1 SONIMV dQ b 30 6 1aa4S 122'-8" j O} Utility and Drainage easement « « 1h3M 01.001. NIA 3 > \ 2 0 e 0 $ m - -H >70 m mƒ 15' 15' - h 0 $ 22 5" O m dOHS 1V13A c▪ o ) \ R 3NI1 AlH3dO1 COMPONENT TO STORMWATER INFASTRUCTURE „0=,09 = G : ]' ' S MUST MAINTAIN A MINIMUM 25-FEET FROM ANY OWTS 0 \ 0 m r r z 0 a 0 e m 0 \ w I m » m 0 \ I ¥ O m @ 0 z z 0 e $ 2 O PROPOSED OWTS = zo,_o„ Utility and Drainage easement Utility and Drainage easement 4" DIA SDR-35 INSPECTION PORT AT BEGINNING AND END OF EACH TRENCH • i s` r, 11111116. •• 1� SibO1N.•..!l'.EI 0 D m m 0 xi = I~o�l z ry 02 N O O _ U'O* — N O O CBO Inc. 33 Four Wheel Drive Road Carbondale, Colorado 81623 Phone 970.309.5259 carla.ostberg@gmail.com z - 0 0'1 u N O O co Gb co Z D 00 71 > D _,� 0< o� 6 _T 0 — — — - — — — — - — o T Metal Shop Big R Subdivision, Lot 4 Garfield County, Colorado Project Number: C1534 o W m Iv N O H x7J >m— � o �D7m z m odm * D H n _i • D D O n W o O 71= ci C) c�i)Oz �`W" D=Ti › comcn m U/ 0 x O< m i n m XI i� iJ cn7om 0 m m D m Zz Zti, cam rJm 0 Ti H m m -0 m m I—= �m 0 H m Z 37) 0 z m c� zo KoD o D = m 0 cn W O) O) 1 —1 cmmm co_m-oc, F m 0 TT z m n C) C) D N m D 1 D -0-15zz0 17 7 T Z m 73 D -I I— * Dmcn=* iom=O c 0m cn m 0 0 Z D coz 0 m D cn 5 H m D n Z ;l m ccn m -1 -Hz mD n m m > Z �111P" 0 0 15' 60' 15, Date: 08/20/20 Designed by: CBO Reviewed by: RB Drawn by: DD W 01 _ W2.0 Sheet 2 OF 4 o X = m D -0 m ^, a % iE56O :JegwnN perald b�0ETeNS (A) b #/ q °§%32 (& Ka (>Di(\ d§3\ g m`` %\5 `= mzm0 q�\ �$ 7(» raw> §9m ®g wz§9®/o c0 k7o 3(\ ; ee� z \ �Zm K 2; all 3132:10NO3 m }§ cox e3 3ovdanS,kdI VOS m > z > Lk. 0 � m 34d?!O 43H 20 R? 0cog (1 a 0. / co co =\\ 0 \ co \ peod OAR] I084M anod ££ • • Aft la ! 0 0 / 17£S60 :JegwnN loafoad \Co. £2El: cn 0 - 3 _ 7 Cn 0 0- 0 ) -. 0 E77 a *Ea Ek \ OCr .< \ O/O \ I0 bdOb3aa4S 007 SIIOS DEPTH - FEET | ' | ' | ' | ' | ' | ' | ' | / _ CO w a a a Co c0 1 0 xz \ c m z0 0 0 0 z 0 0 f m m _ WITH MODERATE STRUCTURE GRADE WVO1 ,WNVS NMO1:18 IHDI1 1 0 0 I\ >0 @* }\ j\ mo �_ ( 0 m i0 co )) /0 z m> \\ \ > m 0 § 0 m eoe000rG E_»/7.E 71o11 2<\%ƒ\±>Cm00 \//)mowI > \�77 k �2�\1�0>K %mC)jm mo:w0mR$�2-o/ >m O-iboo\\m1 z \\>\ ii \� IQ /&==yD\a 0 m=iio¥ /§\=>g13oo §II I21ox@/ >R=2 %)n —1 1Z�� o— z Z Z II01 / m 00eyII3 z = I§§og„ w $ ®~\9 90 m ? m/ 0 \ m j x 1 i z i1 m 0 0 -1 \ ¥ § \ \ c co co m m 73 0 co z 'ON lld lShc 211d02dd IIOS Z'ON lld IShc TIIdOHd BIOS Found #5 Rebar Found #5 Rebar and 1-1/4" Orange Plastic Cap Stamped "LS 27613" Chainlink Fence Barbed Wire Fence 45.0' Utility and Drainage Easement Reception No. 736855 ALTA/NSPS LAND TITLE SURVEY PLAT A Parcel of Land Situate in SWI/4 NW1/4 of Section 11, Township 6 South, Range 93 West of the 6th P.M. County of Garfield, State of Colorado Lot 5 Big R Commercial Park Subdivision Reception No. 736855 Gatepost Gatep st 10.0' Utility Easement Reception No. 736855 _ and Access Easement Reception No. 908370 12.0' Utility and Drainage Easement Reception No. 736855 12.0' Utility and Drainage Easement Reception No. 736855 Lot 4 Big R Commercial Park Subdivision Reception No. 736855 Vacant Lot 2.000± Acres Lot 3 Big R Commercial Park Subdivision Reception No. 736855 Storm. Drain Barbed Wire Fence Bollard Set 18" #5 Rebar and 1-1/4" Orange Plastic Cap Stamped " PROP COR PLS 36572" 10.0' Utility Easement Reception No. 736855 Found #5 Rebar and 1-1/4" Red Plastic Cap Stamping Illegible Found #5 Rebar and 1-1/4" Orange Plastic Cap Stamped "LS 36572" Electric Transformer Underground Electric Gate Post Communications Pedestal UT Underground Telephone Scale 1" = 30' PROPERTY DESCRIPTION THE LAND REFERRED TO HEREIN IS LOCATED IN THE COUNTY OF GARFIELD, STATE OF COLORADO, AND DESCRIBED AS FOLLOWS: LOT 4, BIG R COMMERCIAL PARK SUBDIVISION ACCORDING TO THE PLAT THEREOF RECORDED NOVEMBER 7, 2007 AS RECEPTION NO. 736855. NOTES 1.) DATE OF SURVEY WAS APRIL 27, 2020. 2.) BASIS OF BEARINGS FOR THIS SURVEY IS A BEARING OF NO1 O09'17'E ALONG THE WEST LINE OF LOT 4, BIG R COMMERCIAL PARK SUBDIVISION, RECORDED AS RECEPTION NO. 736855 BETWEEN THE SOUTHWEST CORNER AND THE NORTHWEST CORNER OF SAID LOT 4, THE NORTHWEST CORNER BEING MARKED WITH A #5 REBAR AND THE SOUTHWEST CORNER BEING MARKED WITHA #5 REBAR AND 1-1/4" CAP STAMPED "LS NO. 27613". 3.) SUBJECT PROPERTY IS LOCATED WITHIN AN AREA OF UNDETERMINED FLOOD HAZARDS, BASED ON THE FLOOD INSURANCE RATE MAP (F.LR.M.) COMMUNITY PANEL NO. 0802051360B, GARFIELD COUNTY, COLORADO. 4.) THIS ALTA/NSPS LAND SURVEY PLAT IS BASED ON: a. CONFORMATION DEED RECORDED AUGUST 8, 2012 AS RECEPTION NO. 822541 b. RESEARCH FOR RIGHTS -OF -WAY AND EASEMENTS ARE BASED ON: TITLE COMPANY OF THE ROCKIES, COMMITMENT NO. 1202761-C, EFFECTIVE FEBRUARY 27, 2020 c. MONUMENTS FOUND IN PLACE AS SHOWN HEREON. 5.) ZONE DISTRICT: LOT 4 IS ZONED CG (COMMERCIAL GENERAL). THE RESTRICTIONS FROM THE CURRENT LAND USE CODE (TABLE 3-201 GARFIELD COUNTY LAND USE AND DEVELOPMENT CODE) UPON LOT 4 ARE AS FOLLOWS: MINIMUM LOT AREA 7500 SQUARE FEET; MAXIMUM LOT COVERAGE 85%; MAXIMUM FLOOR AREA RATIO 50%; FRONT SETBACK 25'; REAR SETBACK 7.5; SIDE SETBACK 10' HEIGHT 40'. 6.) BURIED UTILITY RECORD RESEARCH AND ON GROUND UTILITY MARKINGS WERE PERFORMED BY A PRIVATE UTILITY LOCATING COMPANY. THESE MARKINGS WERE SURVEYED BY BOOKCLIFF SURVEY SERVICES, INC. AND REPRESENT LEVELS B, C AND D OF THE ASCE STANDARD GUIDELINES. CALL 811 BEFORE YOU DIG. 7.) ALL DIMENSIONS SHOWN HEREON ARE RECORD AND AS -MEASURED UNLESS OTHERWISE INDICATED. 8.) ALL FOUND OR SET MONUMENTS ARE FLUSH WITH GROUND EXCEPT AS NOTED HEREON. 9.) THE LINEAL UNIT USED IN THE PREPARATION OF THIS PLAT IS THE U.S. SURVEY FOOT AS DEFINED BY THE UNITED STATES DEPARTMENT OF COMMERCE, NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY. 10.) ACCORDING TO COLORADO LAW YOU MUST COMMENCE ANY LEGAL ACTION BASED UPON ANY DEFECT IN THIS SURVEY WITHIN THREE YEARS AFTER YOU FIRST DISCOVER SUCH DEFECT. IN NO EVENT MAY ANY ACTION BASED UPON ANY DEFECT IN THIS SURVEY BE COMMENCED MORE THAN TEN YEARS FROM THE DATE OF CERTIFICATION SHOWN HEREON ALTA/NSPS LAND TITLE SURVEY TO : RIFLE REAL ESTATE SOLUTIONS I, LLC A COLORADO LIMITED LIABILITY COMPANY, TITLE COMPANY OF THE ROCKIES AND JOHN F. BLATZ. THIS IS TO CERTIFY THAT THIS MAP OR PLAT AND THE SURVEY ON WHICH IT IS BASED WERE MADE IN ACCORDANCE WITH THE 2016 MINIMUM STANDARD DETAIL REQUIREMENTS FOR ALTA/NSPS LAND TITLE SURVEYS, JOINTLY ESTABLISHED AND ADOPTED BY ALTA AND NSPS, AND INCLUDES ITEMS 1, 2, 3, 4, 6, 10, 11(a), 11(b), 12, 1 4 . OF TABLE A THEREOF. THE FIELDWORK WAS COMPLETED ON APRIL 27, 2020. s'+ex•' oe ?ail �4�9 f4 a"' �R MICII#siVAANGHORN �'G., •A6572 a c'006fl+®° DESCRIPTION z 0 W �t- 0 J 0 J 0 w 0 0 0 m 0 J J 0I— U) O 0 < Q I--'w0 W QJ J JQ > Q W W Q Et x— m W J N LL FILE: ALTA DFT. YJL CK. MJL DATE: 05/05/20 PROJECT NO. 20025-01 SHEET 1 OF 1