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HomeMy WebLinkAboutPitkin.EH.264514100007 (2017) ONSITE WASTEWATER TREATMENT SYSTEM (OWTS) CONSTRUCTION PERMIT 76 Service Center Rd· Aspen, CO · 81611 Phone: 970.920.5070 Fax: 970.920.5374 Permit #: 0029.2017.POWT Parcel ID #: 2645-141-00-007 Permit Issued: NEW REPAIR REMODEL/ADDITION TANK ONLY FIELD ONLY AMENDMENT Owner(s): 5134 Snowmass Creek Rd LLC Property Address: 5134 Snowmass Creek Rd Legal Description: Size of Lot: 8.7 Acres Detached Accessory Unit: YES NO Barn, Sauna, Greenhouse Size of Building: 7742 ft2 Size of Accessory Unit: TBD This system is designed to serve 6 bedrooms plus a sink in a sauna, a sink in a greenhouse, and a bathroom in a barn. Designed By: SGM Project #: 2016-356.001 Dated: August 22, 2017 Phone #: 970-945-1004 Mailing Address: Fax #: Email Address: LTAR: 0.5 (TL 1) Profile Hole Depth: 8’ Depth to Groundwater or Bedrock:  8’ Minimum Tank Capacity: 2514 gal. Minimum Absorption Area: 1408 ft2 (reduction for dosed chambers) Permit Conditions: This OWTS Construction Permit is approved on the condition of compliance with the engineer design as submitted with the application and the specifications cited above. Changes must be approved by this Department and the engineer prior to construction. This permit is to expand an existing OWTS to allow for an additional bedroom (6 total) and flows from a proposed sauna, greenhouse, and barn. Plant waste and fertilizer shall not be put into the septic system. Any cast iron pipe from the previous OWTS shall not be used and disposed of properly. Sewage will flow via gravity to a new 1250-gallon single compartment tank and then to a 1250-gallon, two-compartment septic tank with a pump installed in the second compartment. Effluent will be pressure dosed to the existing automatic distribution valve and then to the existing 4-trench (72 chamber) soil treatment area. The STA will have an additional 45 total chambers added to end of each trench (about 11 per trench) for a total of 117 chambers. The STA shall be a minimum of 120 feet to any well, 10 feet to the property line, and 70 feet to any unlined irrigation ditch. This Permit must be kept on-site during installation. The engineer must do a final inspection of the installation and submit an "as-built" letter to this Department within 30 days of the final inspection, unless a longer period of time has been agreed upon, in writing. This Department must also be called for the final inspection with a minimum of 48 hours notice. Minimum horizontal distances between components of the system and physical features shall conform to the requirements of the Pitkin County OWTS Regulation. This Permit is conditioned upon the property owner(s) providing for regular inspection, cleaning, and maintenance of the system by qualified personnel, in accordance with the manufacturer's recommendations and the requirements of the Pitkin County OWTS Regulation. Issuance of this OWTS Construction Permit does not constitute a guarantee, warranty, or representation by the Department that the system will operate properly or will not fail. Issuance of this permit does not imply compliance with Pitkin County building and/or land use regulations, nor guarantee issuance of building and/or land use permits. THIS PERMIT IS EXPRESSLY CONDITIONED UPON COMPLIANCE WITH ALL REQUIREMENTS OF THE PITKIN COUNTY OWTS REGULATION, INCLUDING BUT NOT LIMITED TO THOSE CONDITIONS SPECIFIED ABOVE. Plans and specifications for the proposed OWTS have been reviewed and are considered satisfactory. Permission is hereby given to the property owner(s) to perform the work indicated in accordance with the Pitkin County OWTS Regulation. This Permit will expire 1 year from the date of issuance unless construction on the system has commenced. An "as-built" drawing must be submitted and approved by EH before final approval of the system will be issued. Issued By: Kurt Dahl, REHS Date: 10/24/2017 Expires: 10/24/2018 Installer: License #: Reactivation Authorized by: Final Approval Issued By: Date: New Expiration Date: EH/NR Stutsman-Gerbaz Bryan Daugherty, REHS 1/30/20 11 0029.2017.POWT www.sgm-inc.com GLENWOOD SPRINGS 118 West Sixth St, Suite 200 | Glenwood Springs, CO 81601 | 970.945.1004 www.sgm-inc.com GLENWOOD SPRINGS 118 West Sixth St, Suite 200 | Glenwood Springs, CO 81601 | 970.945.1004 SGM Project # 2016-356.001 August 22, 2017 Kurt Dahl 76 Service Center Road Aspen, CO 81611 Subject: OWTS Design 5134 Snowmass Creek Road Snowmass, CO 81615 Mr. Dahl, SGM has prepared an Onsite Wastewater Treatment System (OWTS) design for the subject site at 5134 Snowmass Creek Road (Parcel #264514100007). The design was prepared for OWTS Construction Permit submittal to Pitkin County. SITE CONDITIONS The subject site is approximately 8 acres with an existing residence and an OWTS that was constructed in 2015. The project includes demolition of the existing residence and construction of a new 7,742 square foot, 6-bedroom, single-family residence. A separate sauna structure, greenhouse and barn are being considered as part of the project. The site of the existing OWTS soil treatment area (STA) slopes at approximately 4% to the east, and is located in a meadow with boulders around the perimeter to prevent surface disturbance. The site elevation is 7,670 feet above sea level (NAVD 88). The proposed STA site has been historically used as a pasture. Site features that will require setbacks include a proposed new well, two water storage tanks, an existing irrigation ditch that is to be reconstructed and lined, Snowmass Creek, the proposed single- family residence, and the property boundaries. The existing and re-routed irrigation ditch will be lined within 100 feet of the STA, reducing the setback requirement to 10 feet. All other setbacks will be met for the existing/improved STA and the new septic tank location. The mapped Snowmass Creek floodplain limits are within the 100’ stream setback and all OWTS elements are outside the floodplain limits. PROPOSED CONSTRUCTION The proposed construction will be a single-family residence with 6 bedrooms (approximately 7,742 square feet). The flow rate for the residence is 100 gallons/day/person for an average daily flow of 1,200 gallons/day (gpd). Although not confirmed yet, it is possible that 3 outbuildings will be constructed with some plumbing fixtures. These may include: - A sauna with a sink (5.8 gpd) - A greenhouse with a sink (5.8 gpd) 0029.2017.POWT www.sgm-inc.com - A barn with a bathroom (45 gpd) To accommodate future additions of these structures, we have included an additional 57 gpd, for a total design flow of 1257 gpd. EXISTING SYSTEM DESIGN The existing OWTS was permitted (#0011.2015.POW2) and constructed in 2015 (certified by All Service Septic, October 22, 2015). The system was designed for the existing 5-bedroom, 5,308 sf residence with a design flow of 750 gpd. Based on soil conditions observed in two soil test pits in the vicinity of the STA, an LTAR of 0.5 was used. The STA was constructed in a trench configuration containing four rows of 18 Quick 4 chambers, for a total of 72 chambers. A 2,000-gal, two-compartment tank was installed with an Orenco® Biotube pump vault and PF3005 pump in the second compartment. Effluent is pumped through an Orenco Model 6404 automatic distributing valve (ADV) and then to the STA. RECOMMENDATION The existing OWTS will need to be expanded for the proposed residence with 6 bedrooms and greater than 6,000 sf of floor area which requires a design flow of 100 gal/person/day. The expansion was designed using the 0.5 LTAR used in the 2015 design and a design flow of 1,257 gpd (to accommodate the new residence and potential outbuildings with associated plumbing). A total of 117 Quick 4 chambers are required. We proposed to keep the 72 installed in 2015 and install an additional 45 at the end of the STA trench rows. Minimum septic tank capacity of 2,400 gallons is required. The existing tank is in a location that conflicts with planned site improvements. Consideration will be given to relocating the tank installed in 2015 if tank integrity can be maintained (with appropriate testing and documentation). If the current tank is re-used, a second tank would be added to meet the minimum 2,400-gal capacity. However, this permit application assumes new tanks will need to be installed. Sewer Pipe: Sewer pipes shall be 4-inch SCH40 PVC pipe installed with a minimum slope of 2%. Joints shall be solvent welded. Cleanouts are required 1) at the stubout from the building, 2) at spacing not to exceeding 100 feet, and 3) upslope of two or more bends closer than ten feet in the sewer pipe. Bends in the sewer pipe shall not exceed 45 degrees. The pipe shall be properly bedded per the typical trench detail presented on the design drawings. The septic tank shall: 1) be located down gradient of the home, 2) be buried no deeper than three feet, and 3) be at a location accessible for siphoning and maintenance at the tank. The installer must coordinate with the general contractor as to the elevation of the stubout. A septic tank deeper than 3 feet will not be allowed. If SGM can assist with locating the septic tank after the stubout location is identified, please call. 0029.2017.POWT www.sgm-inc.com Septic Tanks: Two tanks shall be installed: a 1,250-gallon, one-compartment tank and a 1,250- gallon, two-compartment tank with an Orenco® Systems, Inc. Biotube pump vault. The tanks and lids shall conform to current County OWTS regulations. The tanks shall be installed with insulated, watertight access risers with lids that can be secured. The effluent filter handle and float tree handle in the second tank shall extend to within six to twelve inches of the lid. The electrical control panel shall be installed on the exterior of the structure with a line of site to the pump vault riser. Controls and alarms shall be listed per UL 508. The control panel for the STA dosing chamber pumps shall be an Orenco® MVP-DAX1DMHT unit unless the existing control panel is shown to meet requirements and be in good working order. The panel shall be weatherproof to protect against adverse weather conditions. Pumping System: The Orenco® Model PF3005 pump installed in 2015 can be used with the expanded system. The dosing tank control system shall have 3 floats: 1) High Water Alarm Float, 2) Pump ON Float and 3) Pump OFF Float. The STA dosing volume shall be 210 gallons. Automatic Distribution Valve (ADV): The existing system includes an Orenco® Model 6404 automatic distribution valve (ADV) which feeds the four trenches. The existing ADV will remain in place. Soil Treatment Area: The STA expansion is to be field fit to extend the existing trenches by the required number of chambers. The expanded trenches are to be constructed in accordance with the details indicated in the plans. 45 Quick 4 chambers shall be placed as indicated on the design drawings. The existing 1.25” PVC laterals will be extended and hung with zip ties from the underside of the new chambers. Hole patterns for the laterals will match the existing with 5/32-inch diameter orifice holes facing up with the exception of the first and last holes facing down for drainage. Holes were placed 3 feet on center. Existing flushing valves will be relocated to the ends of the extended trenches. The expanded STA shall be covered with a minimum of 12-inches of soil as measured after settlement. This may mean that the STA cover will have to be 16+-inches when in place to allow for settlement over the freeze-thaw of a winter season. The surface of the STA shall be seeded after installation of the system. A seed mix approved by Pitkin County shall be used. These mixes do not require irrigation and develop a growth 10 to 15 inches high. No automatic sprinkler system shall be installed over the STA. Vehicular traffic and livestock shall be kept off of the STA. No landscaping or plastic sheeting can be used over the STA, which will reduce performance of the STA. INSTALLATION OBSERVATIONS The installation of the OWTS shall be observed by the design engineer. A final dosing observation will be required prior to placing the OWTS into service. Our office shall be called at 970-945-1004 to observe the installation at least 24 hours in advance. 0029.2017.POWT www.sgm-inc.com OPERATION AND PREVENTATIVE MAINTENANCE SCHEDULE The goal of an operation and maintenance schedule is to observe the operation, and perform minor maintenance to the onsite wastewater system to allow for proper, long-term functioning of the system. Septic tanks: The scum and sludge accumulation in the septic tanks shall be monitored yearly. Once the cumulative scum or sludge thickness reaches 25% of the tank depth, the entire tank shall be pumped. A pumping frequency of 1 to 3 years is expected at design flows. An alternative is a regular pumping frequency of every 2 years. Filter and Effluent Pumping System: The effluent filter at the septic tank discharge shall be cleaned (hosed off) at the time of pumping or as needed. The effluent pumps shall be checked semi- annually to ensure pumps are functioning properly. If the alarm sounds, the pumps and floats shall be checked and/or serviced immediately. General: System users must realize that an on-site wastewater treatment system is different from public sewer service. There are daily considerations such as not putting plastic or other non- biodegradable material into the system. Water use shall be monitored so that toilets are not allowed to leak when seals malfunction. Allowing fixtures to flow continuously to prevent water lines from freezing is not acceptable. Although the proposed system can accommodate variable flows, spreading water use over several hours and eliminating peak flows is recommended. To illustrate the point, a malfunctioning toilet can discharge in excess of 1,000 GPD. Excessive daily loading could flood and irreparably harm the OWTS. SGM recommends against installation of a water softener. The chemical and hydraulic loading from the backwash of a water softener would be damaging to the OWTS and a separate drywell shall be constructed for the backwash waste, if a softener is installed. No landscaping or plastic can be used over the STA, which would reduce the performance of the STA. The design of the OWTS is based on the treatment of domestic sewage only. Swimming pool or spa water is not to be discharged into the OWTS. The proposed OWTS design is based on the regulatory flows noted in the report. Increased flows may hydraulically or organically overload the OWTS, causing premature failure. LIMITATIONS Our investigation, layout, design, and recommendations are based on data submitted. If conditions that are considerably different from those described in this report are encountered, SGM shall be called to evaluate the conditions. If the proposed construction is changed, SGM shall be notified to evaluate the effect of the changes on the OWTS. All construction shall be in accordance with the 0029.2017.POWT www.sgm-inc.com Pitkin County OWTS regulations. Pipe type and size, burial requirements, septic tank construction, and other specifications, which are not depicted in our report, shall conform to the requirements of the Pitkin County OWTS regulations. The installer of the system shall be licensed by the Pitkin County Environmental Health Department and shall have demonstrated knowledge of the Pitkin County OWTS regulations and requirements. If there are any questions or if we may be of further service, please call. Sincerely, SGM Reviewed By: Matthew T. Webster Jay Hammond, P.E. Chief Operating Officer Principal – Aspen Office 0029.2017.POWT Pump Selection for a Pressurized System - Single Family Residence Project 5134 Snowmass Creek Rd Parameters Discharge Assembly Size Transport Length Before Valve Transport Pipe Class Transport Line Size Distributing Valve Model Transport Length After Valve Transport Pipe Class Transport Pipe Size Max Elevation Lift Manifold Length Manifold Pipe Class Manifold Pipe Size Number of Laterals per Cell Lateral Length Lateral Pipe Class Lateral Pipe Size Orifice Size Orifice Spacing Residual Head Flow Meter 'Add-on' Friction Losses 1.50 471 40 1.50 6404 25 40 1.25 28 0 40 1.25 4 120 40 1.25 5/32 3 5 None 0 inches feet inches feet inches feet feet inches feet inches inches feet feet inches feet Calculations Minimum Flow Rate per Orifice Number of Orifices per Zone Total Flow Rate per Zone Number of Laterals per Zone % Flow Differential 1st/Last Orifice Transport Velocity Before Valve Transport Velocity After Valve 0.68 41 30.5 1 36.9 4.8 6.6 gpm gpm % fps fps Frictional Head Losses Loss through Discharge Loss in Transport Before Valve Loss through Valve Loss in Transport after Valve Loss in Manifold Loss in Laterals Loss through Flowmeter 'Add-on' Friction Losses 2.8 25.5 7.1 2.9 0.0 4.7 0.0 0.0 feet feet feet feet feet feet feet feet Pipe Volumes Vol of Transport Line Before Valve Vol of Transport Line After Valve Vol of Manifold Vol of Laterals per Zone Total Vol Before Valve Total Vol After Valve 49.8 1.9 0.0 9.3 49.8 11.3 gals gals gals gals gals gals Minimum Pump Requirements Design Flow Rate Total Dynamic Head 30.5 75.9 gpm feet 0 5 10 15 20 25 30 35 0 50 100 150 200 250 300 Net Discharge (gpm) PumpData PF3005 High Head Effluent Pump 30 GPM, 1/2HP 220V 1Ø 50Hz PF3007 High Head Effluent Pump 30 GPM, 3/4HP 220V 1Ø 50Hz PF3010 High Head Effluent Pump 30 GPM, 1HP 220V 1Ø 50Hz PF3015 High Head Effluent Pump 30 GPM, 1-1/2HP 220V 1Ø 50Hz Legend System Curve: Pump Curve: Pump Optimal Range: Operating Point: Design Point: 0029.2017.POWT 0029.2017.POWT 0029.2017.POWT 0029.2017.POWT 0029.2017.POWT 0029.2017.POWT 0029.2017.POWT 0029.2017.POWT 0029.2017.POWT PLEASE CHECK EACH ITEM TO INDICATE COMPLETION Only one copy of each item is necessary. OWTS Construction Permit Application (completed) Site Plan All designs must be 1" to 20' in scale. Soil Testing Notification & Report (must be provided by a PE) Report must include percolation test results and the soil profile evaluation. Building Floor Plans Land Use Approvals & Other Relevant Permits & Approvals Electronic document emailed to before the date of the pre-application conference Recorded Site Plan that designates approved envelope(s) for development. Proof of Adequate Water Supply Public systems: Applicable Fee Tank Only: $523 There is an additional Administrative Fee of $175 for properties in the Town of Snowmass Village. A complete application package must be presented at the time of submittal for acceptance. To schedule a pre-application conference, please call 970-920-5070. Please Make Checks Payable To: Pitkin County Environmental Health Department Legal water supply must be demonstrated in accordance with Colorado water law and meet the requirements of the Pitkin County Land Use Code. OWTS Construction Permit: $1,023 Proof generally includes a well driller's report, well permit issued by the Colorado Division of Water Resources, final augmentation plan (if required), and a recent pumping report. Wells must be drilled before an application will be accepted. Proof generally includes a letter from the CWQCD - approved public water system confirming it has sufficient water to supply the development and it has agreed to do so. ONSITE WASTEWATER TREATMENT SYSTEM (OWTS) CONSTRUCTION PERMIT APPLICATION CHECKLIST 76 Service Center Rd · Aspen, CO · 81611 Phone: 970.920.5070 Fax: 970.920.5374 Private systems: Submit electronically to before the date of the pre-application conference. Comments from EH/NR regarding Land Use review referrals can be accessed by opening http://pitkincounty.com/454/Online-Search and choose "Planning", enter address, parcel or owner information to search. Referral comments more than 2 years old may need to be requested from the County Planning Department. Site plan must include locations of existing wells, buildings, property lines, ditches, water lines, springs, irrigation lines, drinking water cisterns, drain tiles, water bodies, wetlands, riparian areas, floodplains, dry gulches, and existing OWTSs. Copies of all land use approvals, as well as all other documentation relevant to the siting of the OWTS(s) and any other development on the property (e.g., Resolutions, Administrative Decisions, recorded easements). This Department should be notified when soil tests are conducted. A 2"- 4" perforated PVC pipe should be placed in the soil profile hole for monitoring purposes. If the property is exempt from this requirement, please have a Community Development Planner email with confirmation of the exemption. Electronic document emailed to before the date of the pre-application conference EH 0029.2017.POWT www.s gm-inc .com GLENWOOD SPRINGS 118 West Sixth St, Suite 200 | Glenwood Springs, CO 81601 | 970.945.1004 January 27, 2020 PITKIN COUNTY ENVIRONMENTAL HEALTH DEPARTMENT Attn: Kurt Dahl 76 Service Center Road Aspen, CO 81611 RE: OWTS Design 5134 Snowmass Creek Road Snowmass, CO 81615 Parcel ID #264514100007 Pitkin County Environmental Health Department: This letter is intended to fulfill the Pitkin County requirements for the certification of construction of the Onsite Wastewater Treatment System (OWTS) for the property located at 5134 Snowmass Creek Road, Pitkin County, Colorado. This work was completed under Pitkin County Onsite Wastewater Treatment System Construction Permit No. 0029.2017.POWT. SGM performed the last OWTS observation on January 14, 2020. SGM compiled a record survey after the septic components were installed and has provided this information on the accompanying record drawings. The installation of the septic tank and related excavation was performed by Stutsman Gerbaz Earthmoving of Snowmass, Colorado. Pumps and appurtenances were installed by Valley Precast of Buena Vista, Colorado. SGM performed several site visits during construction to observe the OWTS installation. - 9/21/2018: we observed the OWTS soil treatment area trench extensions, including verifying the tie-in to the existing field, the number of Quick4 chambers added to the field, the use of pipe hangers, the installation of observation pipes at the ends of the rows, and the relocation of the flushing valves to the new ends of the rows. - 10/18/2018: we observed the installation of the tanks, piping, bedding and backfill. - 1/14/2020: we observed the pump performance, including manual pump activation, automatic pump activation and shut off at appropriate levels. We observed effluent reaching the end of one row of infiltrators. We observed that the high-level alarm was functional. We also are attaching a letter from Valley Precast (1/14/2020) indicating that the system was started properly and went through several pump cycles with no issues. www.sgm-inc.com January 27, 2020 Pitkin County Environmental Health OWTS Certification Letter Page 2 of 2 The intent of this letter, along with the accompanying record drawings, is to provide adequate information to convey that the installation of the OWTS improvements for 5134 Snowmass Creek Road were completed in general conformance with the approved plans and specifications prepared by SGM. Please feel free to contact us if we may provide further information or provide you with copies of any of the photographs that were taken during the observations by SGM. Sincerely, SGM Reviewed By: Matthew T. Webster Jay Hammond Chief Operating Officer P.E.Principal, Aspen Office COMMUNITY DEVELOPMENT DEPARTMENT 130 South Galena Street Aspen, Colorado 81611 Phone (970) 920-5526 FAX (970) 920-5439 RE:PID # Pitkin Building #: Date: Inspection Results: Accepted Rejected (See Comments) Signature of Applicant: __________________________________________________________ Print Name: Date: Accepted as Noted ( See Comments) Partial ( See Comments) Signature of Inspector: __________________________________________________________ Print Name: Date: Type: Comments: DepartmentNA Rejected Hold Accepted Expired Canceled CounterInitiate EHOWTS Planning PlanningEngineer Zoning PWEngineer HPC FinalApproval CounterIssue FinalInspections PermitCoordinatorCO Archive OnsiteWastewaterTreatmentSystem(OWTS) RoutingStatus 0029.2017.POWT S S S S S Graphic Scale In Feet: 1" = 20' 0 10 20 40 C.1.01 OWTS Record Drawing 51 3 4 S n o w m a s s C r e e k R o a d Pi t k i n C o u n t y , C o l o r a d o 2016-356.001 AWA 02.06.2019 JWH 5134SnowmassCk_OWTS_Cert 11 8 W e s t S i x t h S t r e e t , S u i t e 2 0 0 Gl e n w o o d S p r i n g s , C O 8 1 6 0 1 97 0 . 9 4 5 . 1 0 0 4 w w w . s g m - i n c . c o m JWH