HomeMy WebLinkAbout4730 Sweetwater Rd - 186113120002Environmental Health Department P.O. Box 179 500 Broadway Eagle, CO 81631-0179 Phone: (970) 328-8730 Fax: (970) 328-7185 Permit Permit No. OWTS-024162-2022 Permit Type: OWTS Permit Work Classification: New Permit Status: Active Issue Date: 7/26/2022 Expires: 11/23/2022 On-Site Wastewater Treatement System Project Address Parcel Number 4730 SWEETWATER RD, GYPSUM AREA,186131200002 Owner Information Address Travis Achen Phone: (928) 853-1904 Cell: Email: travis.achen@gmail.com Inspections: For Inspections Call: (970) 328-8755 Engineer Phone Email LKP Engineering, Inc., Luiza Petrovska, PE (970) 390-0307 luiza@lkpeng.com Contractor License Number Phone Email Logan Inc loganinc04@aol.com(970) 314-3659OWTSPL-000188-20 22 Permitted Construction / Details: nstall the OWTS exactly as depicted in the LKP Engineering design, stamped, signed, an dated March 1, 2022. The OWTS is designed to serve a new four bedroom single family residence. The OWTS consists of a 1500 gallon three-compartment Valley precast with effluent filter between the second and third compartment and an Orenco high head pump model PF5005 and pump assembly in the third compartment. Set floats to deliver effluent approximately feet to the soil treatment area which consist of 68 Infiltrator Quick4 chambers, four rows of 17 chambers, in a 2-foot sand filter bed. Graduation meeting secondary sand must completed within one month of obtaining the sand and provided with the final certification. The location of the new well must be identified prior to beginning installation of field and upon final inspection and record drawing. Note: If the septic tank is located within the area of a future driveway the tank and lines must be configured for traffic loading and the tank lids for all three compartments remain accessible at grade. Contact Eagle County Environmental Health and the design engineer well in advance of requesting inspections prior to backfilling any component of the OWTS. The design engineer is responsible for conducting all inspections necessary to certify the installation and assure the functionality of the system. System certification, along with photos and a record drawing is required to be submitted to and approved by Eagle County Environmental Health prior to the use of the system or occupancy of the home. THIS PERIMT EXPIRES BY TIME LIMITATION AND BECOMES NULL AND VOID IF THE WORK AUTHORIZED BY THE PERMIT IS NOT COMMENCED WITHIN 120 DAYS OF ISSUANCE, OR BEFORE THE EXPIRATION OF AN ASSOCIATED BUILDING PERMIT Issued by: Environmental Health Department, Eagle County, CO Claire Lewandowski Date July 26, 2022 CONDITIONS 1. 2.ALL INSTALLATIONS MUST COMPLY WITH ALL REQUIREMENTS OF THE EAGLE COUNTY PUBLIC HEALTH AGENCY ON-SITE WASTEWATER TREATMENT SYSTEM REGULATIONS ADOPTED PURSUANT TO AUTHORITY GRANTED IN CR.S. 25-10-101, et seq., AS AMENDED 3.THIS PERMIT IS VALID ONLY FOR PERFORMING WORK ON OWTS ASSOCIATED WITH STRUCTURES WHICH HAVE FULLY COMPLIED WITH COUNTY ZONING AND BUILDING REQUIREMENTS CONNECTION TO, OR USE WITH, ANY DWELLING OR STRUCTURE NOT APPROVED BY THE ZONING AND BUILDING DEPARTMENTS SHALL AUTOMATICALLY BE A VIOLATION OF A REQUIREMENT OF THE PERMIT AND WILL RESULT IN BOTH LEGAL ACTION AND REVOCATION OF THE PERMIT 4.1.6(A)(1) EAGLE COUNTY PUBLIC HEALTH AGENCY ON-SITE WASTEWATER TREATMENT SYSTEM REGULATIONS REQUIRES ANY PERSON WHO CONSTRUCTS, ALTERS OR INSTALLS AN ON-SITE WASTEWATER TREATMENT SYSTEM TO BE LICENSED Tuesday, July 26, 2022 1 INSPECTION WORKSHEET (INSP-520257-2023) FOR EAGLE COUNTY GOVERNMENT OWTS-024162-2022Case Number:Case Module:Permit Management 09/20/2022 ApprovedInspection Status:Inspection Date: OWTS Final InspectionInspection Type:Inspector:Claire Lewandowski Job Address:Parcel Number:4730 Sweetwater Rd Gypsum Area, CO 186131200002 Company Name NameContact Type Contractor Logan Inc Logan Satterfield Engineer LKP Engineering, Inc.Luiza Petrovska, PE Owner Travis Achen CommentsPassedChecklist Item True Observed in compliance.Septic Tank - Septic Tank True Received.Record Drawing - Record Drawing True Received.Record Photos - Record Photos True Sand gradation confirms secondary sand specifications were met. Site and Soil - Site & Soil True Final certification received. Stamped and signed by Luiza Petrovska, PE. Final Certification Letter - Final Certification Letter True In compliance. Setback to Sweetwater creek was observed greater than 50 feet. General Plan - General Plan True Observed in compliance.Soil Treatment Area (STA) - Soil Treatment Area (STA) True Eagle County OWTS licensed installer Logan Satterfield completed the installation. Identification of Systems Contractor - Identification of Systems Contractor January 24, 2023 Page 1 of 1P.O. Box 179, 500 Broadway, Eagle, CO 81631-0179 P.O. Box 724, Eagle, CO 81631 Tel. 970-390-0307 www.LKPEngineering.com March 1, 2022 Travis Achen P.O. Box 629 Avon, CO 81620 travis.achen@gmail.com RE: Soil and Site Evaluation Achen 4-Bedroom Residence Major OWTS-Replacement Parcel of Land in Section 31, T3S R86W, 6th PM 4730 Sweetwater Road Eagle County, Colorado Project No. 21-3574 Dear Travis, On February 22 and 25, 2022, we visited your property on a Parcel of Land in Section 31, T3S R86W, 6th PM, 4730 Sweetwater Road, Eagle County, Colorado. The purpose of our site visits was to select an area on your property for the proposed new Soil Treatment Area for a major repair/replacement of the existing septic system. During the first site visit, the excavator/installer Travor Dunsdon, with Alpha Excavation, dug two profile holes. During the second site visit, the excavator/installer Logan Satterfield with Logan, Inc., dug a third profile hole. Also, during the second site visit, Logan told us that the old system was on the east side of the existing cabin and consisted of a 4x6 container covered with a piece of plywood. The OWTS is for a proposed 4-bedroom residence, and it will consist of a 1500-gallons, three-compartments concrete septic tank by Valley Precast with an effluent filter, and an Orenco Pump assembly, and the Soil Treatment Area will consist of 68 Quick 4 Plus, Standard Infiltrator Chambers in a bed configuration with a 2-foot sand filter and pressure dosing. The septic tank might be within the area where future driveway or parking might be crossing, and must be built accordingly for traffic loading. The as-built survey by Matt Slagle, PLS CFedS, Slagle Survey Services, was used as a basis for the septic system design. Directions to the site from the Dotsero are as follows: take Exit 133 on I-70 northwest on Colorado River Road for about 6.9 miles to Sweetwater Road, left on Sweetwater Road, continue for 4.6 miles to 4730 Sweetwater Road. The property is on the left side of the road. ! Preliminary Investigation G Address: 4730 Sweetwater Road, Gypsum CO 81632. G Legal Description: PCLIN Section: 31 Township: 3 Range: 86, Eagle County, Colorado. G Existing Structures: There an existing 2-bedroom cabin on the property. G Location of existing and proposed wells on property: The proposed well will be drilled NW from the proposed STA, into the canyon. 4730 Sweetwater Road March 1, 2022 Page 1 of 2 Project 21-3574 P.O. Box 724, Eagle, CO 81631 Tel. 970-390-0307 www.LKPEngineering.com G ECEHD (Eagle County Environmental Health Department) records: Thorough search by Claire Lewandowski, REHS G Environmental Health Specialist III, was done and she was not able to locate a permit record. The county records show that the house was built in 1943. G G Topography: The topography of the leachfield site is relatively flat to moderate with an average slope of about 7 percent. Drainage is to the north, toward Sweetwater Creek G Soil Data: The profile holes were observed on February 22 and 25, 2022. The soil exposed in the profile holes was as follows: Profile Hole #1 0 to 1.0 feet topsoil with roots 1.0 to 8 feet brown, sandy clay loam, silty, gravelly with angular cobbles and boulders no ground water encountered dug 2/22/2022 Profile Hole No. 2 0 to 1.0 feet topsoil with roots 1.0 to 4.5 feet light brown, clay loam, silty, sandy with roots 4.5 to 7.5 feet brown, sandy clay loam, silty, gravelly with angular cobbles and boulders no ground water encountered dug 2/22/2022 Profile Hole No. 3 0 to 4 feet man-made fill with debris, wire, plywood, topsoil, sand, etc. 4 to 5 feet topsoil with roots 5 to 8 feet brown, sandy clay loam, silty, gravelly with angular cobbles and boulders no ground water encountered dug 2/25/2022 A soil sample taken from Profile Hole # 1 at 48-inches was classified as Type 3, LTAR = 0.35 gpd/sf with >35% Rock (>2mm) SANDY CLAY LOAM, R-1, Option 1 A soil sample taken from Profile Hole # 2 at 48-inches was classified as 4730 Sweetwater Road March 1, 2022 Page 1 of 2 Project 21-3574 P.O. Box 724, Eagle, CO 81631 Tel. 970-390-0307 www.LKPEngineering.com Type 3, LTAR = 0.35 gpd/sf with <35% Rock (>2mm) CLAY LOAM Profile Hole 3 had similar soil with Profile Hole 1 below the fill layer. Recommended: Use pressure distribution, with 2 feet of unlined sand filter (secondary sand assumed) LTAR of the receiving soil for TL3 (Table 10-1) = 0.65gpd/sf G Location of applicable setbacks in Table 7-1 ! Reconnaissance G Landscape position: The proposed STA will be located in the Toe Slope Position east from the existing cabin G Topography: The topography of the proposed leachfield site is flat to moderate. The rows of infiltrators in the bed will run along the contours. G Vegetation: The vegetation within the proposed leachfield site consisted of grass. At the time of the two site visits, the site was covered with snow. The site surrounding the STA consists of evergreen forest and cottonwood trees. G Natural and cultural features: The property is located within the Sweetwater Creek Watershed, about 4.5 miles upstream from the confluence with Colorado River, Eagle County, Colorado. Interstate 70 is about 11 miles to the south. G Current and historic land use: The current use is residential. Prior appears to have been residential as well. ! Detailed Soil Investigation G Visual and tactile evaluation of two or more soil profile test pit excavation; Three profile holes were dug, observed and logged and visual and tactile evaluation test was done. G Percolation tests plus one or more soil profile holes or one or more profile test pit excavations: Three profile holes were observed and logged on February 22 and 25, 2022. ! Report and Site Plan G Name, address, telephone number, email address, and credentials and qualification of individual who conducted site evaluation: This site evaluation was completed by Luiza Petrovska, PE, of LKP Engineering, Inc. LKP Engineering, Inc., is located at 67 Robins Egg Lane, Eagle, Colorado. The phone number is 970-390-0307 and Luiza=s email is luiza@lkpeng.com G Dates of preliminary and detailed evaluation: February 22 and 25, 2022. G A graphic soil log, to scale: Attached G Setback distances in Table 7-1: 4730 Sweetwater Road March 1, 2022 Page 1 of 2 Project 21-3574 P.O. Box 724, Eagle, CO 81631 Tel. 970-390-0307 www.LKPEngineering.com G Setback distances in Table 7-2: Items 1-4, observed. No ground water encountered. G A drawing (to scale) with complete property boundary lines on minimum of 8.5 x 11" # Label profile test pits/holes # North Arrow # Graphic scale # Horizontal and vertical reference points of proposed STA # Contours OR slope direction and % slope # Location of any visible or known unsuitable, disturbed, or compacted soils # The proposed elevation of the infiltrative surface of the STA from benchmark or ground surface G Anticipated construction related issues: none G Assessment of known or foreseeable land use changes expected to affect the system performance: None known. G Narrative explaining difficulties encountered during site evaluation: none The graphic soil log is appended to this report. LKP Engineering, Inc. Luiza Petrovska, PE Enclosure J:\_WP X4-LKP\_2021\21-3574SOIL-SITE-EVAL-BED-PRESS-SAND-MAJORREPLACE.DOCX Well (not constructed at the time of the study) Structure w/o basement PL Lake Surface Water Septic Tank Tank >50’ ~7.8’ ~90’NPL 50’ - STA >100’ ~20’ ~100’PL ~51’ ~6.6’ мͿйкͿлйлл P.O. Box 724, Eagle, CO 81631 Tel. (970) 390-0307 www.LKPEngineering,com September 26, 2022 Travis Achen P.O. Box 629 Avon, CO 81620 travis.achen@gmail.com RE: Inspection of Septic System Installation Achen 4-Bedroom Residence Major OWTS-Replacement Parcel of Land in Section 31, T3S R86W, 6th PM 4730 Sweetwater Road Eagle County, Colorado Project No. 21-3574– OWTS-024162-2022 Dear Travis: At the request of your installer, Logan Satterfield, Logan Inc., and at your request, on September 14 and 20, 2022, we visited your property on a Parcel of Land in Section 31, T3S R86W, 6th PM, 4730 Sweetwater Road, Eagle County, Colorado. The purpose of our site visits was to inspect the installation of the septic system. The system was installed in overall compliance with the septic system design, Drawing No. 21-3574OWTS.dwg, dated March 1, 2022. At the time of the inspection, we observed the following: They installed 1500-gallons, three compartments, concrete septic tank with H-20 Loading, and with an Orenco PF500511 high-head pump assembly, by Valley Precast, Inc. In the second access port of the septic tank, an effluent filter was installed with the handle extended close to the top of the riser. The septic tank had concrete risers and metal frames and covers. The risers were of variable heights, with the inlet compartment having 26-inch riser, the middle compartment 29-inch riser, and the pump compartment having 31-inch riser. The control panel was installed on the east side of the cabin, north of the electric meter. The building sewer line was about 14 feet long, 4-inch diameter, sch40 pvc with a cleanout at 3 feet from the building, as shown on the attached, as-built sketch. The effluent line from the pump chamber to end manifold of the soil treatment area, was about 19-feet long, 1.5-inch diameter, sch40 pvc pipe. The end manifold was about 8.5-feet long, 1.5-inch sch40 pvc. The soil treatment area consisted of infiltrator chambers arranged in a bed configuration with four rows of 17 Quick Four Plus Standard Infiltrator Chambers in each. Two feet of the onsite soil were overexcavated from the bottom of the STA and replaced with two feet of secondary sand media (the sand spec is attached to this report). Pressure dosing system consisting of 68-ft, 1.25-inch sch40 laterals perforated at the top with 1/8-inch holes at 4-ft intervals, suspended from the side of each row of infiltrator chambers. The ends of the laterals were equipped with flushing assemblies. A squirt test was performed during the inspection, and it was satisfactory. Claire from the ECEH Department was present during the inspection and the squirt test. All inspection ports were installed 4730 Sweetwater Road September 26, 2022 Page 1 of 2 Project 21-3574 P.O. Box 724, Eagle, CO 81631 Tel. (970) 390-0307 www.LKPEngineering,com (in the end caps of the first and last chamber of each row of infiltrators) in the openings opposite the pressure distribution lines. The system installation and the startup of the pump system were done by the installer, Logan Satterfield, Logan Inc., and by Valley Precast. There is no other warranty either expressed or implied. Sincerely, LKP Engineering, Inc. Luiza Petrovska, PE cc: Eagle County Environmental Health Department E-mail: Claire Lewandowski claire.lewandowski@eaglecounty.us; environment@eaglecounty.us J:\_WP X4-LKP\_2021\21-3574OSIQ4PLUS-BED-SAND-OEX-PRESSURE.DOCX 9/26/2022 NORTH S W E E T W A T E R CR E E K 1500 GALLONS, H-20 TRAFFIC LOADING, THREE COMPARTMENTS CONCRETE SEPTIC TANK WITH EFFLUENT FILTER AND ORENCO PUMP ASSEMBLY BY VALLEY PRECAST OR EQUIVALENT ABOUT 14 FEET OF 4-INCH DIAMETER SCH40 PVC, BUILDING SEWER LINE ABOUT 19 FEET OF 1.5 INCH SCH40 PVC TRANSPORT (EFFLUENT LINE) CLEANOUT FLUSHING ASSEMBLY THROUGH THE END CAPS SEE DETAIL INSPECTION PORT (TYPICAL IN THE FIRST AND LAST INFILTRATOR CHAMBER OF EACH ROW, INSTALLED IN THE OPENING OF THE CAP OPPOSITE OF THE PRESSURE LINE ~68 FEET OF 1.25-INCH SCH40 PVC LATERAL, PERFORATED WITH 1/8-INCH HOLES AT 4-FOOT INTERVALS AT THE TOP OF THE PIPE (TYPICAL) END CAP (TYP) ~ 8.5' END MANIFOLD, 1.25 INCH DIAMETER SCH40 PVC STA BED WITH FOUR ROWS OF 17 INFILTRATOR CHAMBERS EACH QUICK 4 PLUS, STANDARD INFILTRATOR CHAMBER (TYPICAL) APPROXIMATE LOCATION OF NEW BRIDGE 24.7'29.6 ' CONTROL PANEL TO N E A R T H E EXI S T I N G W E L L ~16 0 ' + / - SKETCH PROJECT NO.: DATE: PROJECT DESCRIPTION:LKP Engineering, Inc. CIVIL/GEOTECHNICAL PERMIT NO.:AS-BUILT 21-3574 OWTS-024162-2022 September 20, 2022 P.O. Box 724 Eagle, CO 81631, (970) 390-0307, www.LKPEngineering.com TRAVIS ACHEN RESIDENCE PARCEL OF LAND IN SECTION 31, T3S, R86W, 6TH P.M. 4730 SWEETWATER ROAD EAGLE COUNTY, COLORADO March 2, 2021 – UPDATED 4/28/2021 Ms. Nicole Mosby, PE, CFM Eagle County Engineering Department Sent via email: Nicole.mosby@eaglecounty.us RE: Floodplain analysis for 4730 Sweetwater Creek Road, Eagle County (Gypsum address), Colorado Dear Nicole, Thank you and Julie’s assistance in directing us to the previous information for the above parcel. As you know, this parcel has a new owner who is looking to develop the existing cabin area for a single-family home. The site is approximately 4.5 miles up Sweetwater Creek Road, on the south side of the road. The parcel has the creek bisecting it draining generally west to east. Currently, there are two small “hunting” cabins on the roadside of the creek, and a larger, permanent cabin on the far side of the creek. The only access is a rather rickety footbridge near the east end of the property. It is not known exactly when these structures were built. Title information indicates this property was active in the 1950-1960’s. Mere observance of the construction of the main cabin indicate this structure can well be several decades old, correlating with that mid-20th century timeframe. In general, to appropriately use the cabin and the buildable space for the parcel the applicant must cross the creek with a suitable bridge for even emergency vehicles and is willing to do so. The general progress of their application will be associated with a more full site review, but some of those elements, such as geotechnical assessment or septic system design and construction, warrant a sufficient bridge just to get across and make appropriate design analysis for the rest of the site. This bridge, along with the desired site development plans, prompt our submittal of this report and associated calculations for your review and approval as an early step in the overall site review process. The applicant understands the need for a vehicular access across the creek, sufficient for fire / emergency use. They also desire to maximize buildable space with this analysis on the far side of the creek, targeting the minimum setback allowed from normal high water. Our modeling was to affirm existing conditions, model a proposed bridge to see 1) proposed bridge impacts and; 2) site work alteration limitations. www .s gm-in c .co m GLENWOOD SPRINGS 118 West Sixth St, Suite 200 | Glenwood Springs, CO 81601 | 970.945.1004 Previous Information As part of some previous work completed in the spring of 2020, an initial study from LKP Engineering was completed and submitted to your office and, while not recorded as this is an unmapped area, your review seemed to indicate general acceptance to the existing conditions flood model. As noted in that LKP report, this area is Zone D (December 2007 effective date), or “undetermined” flood zone, hence that initial study from LKP was completed for an initial analysis. We affirm this current status. The initial model utilized the USGS Streamstats to develop the hydrology for the creek. The LKP report indicated a calculated flow of 1920 CFS for the 100-year flood. To reproduce this, we likewise utilized Streamstats and were able to reasonably replicate using the USGS online server. Upon study of the Streamstats and LKP data, we recognized that neither take into account the legitimate attenuation Sweetwater Lake would provide in the overall basin. Approximately 60% of the basin to the point of 4730 passes through Sweetwater Lake which would greatly slow and “flatten” the storm peak. This report is to represent our approach to accurately model that reality. Further, we assert that the topography from the timeframe of the LKP study was not sufficient for accurate modeling of the creek, stopping topography at the east property line, just 30 or so feet downstream of the proposed bridge location. We have subsequently acquired additional survey data from Slagle (same survey as the April study) an additional 250 feet down stream to better understand those tailing flows and provide ample modeling space to assure downstream impacts on the neighboring property. This, too, has provided additional confirmation we desired. As with the LKP data, we utilize AutoCAD 2020 Civil 3D for the digital files and Hec-RAS 5.0.7. We acquired the Streamstats data and input those basin parameters into HydroCAD, a TR-20 based software with NOAA hydrology to determine the impacts of the lake. Cross sections at the parcel were taken from the afore-mentioned topography with an attempt to be in close proximity to the previous model, with added sections for the bridge and the additional topography downstream. For Sweetwater Lake itself, topography was acquired from the USGS 1-meter data and converted to 2-foot contour mapping for evaluation of Sweetwater storage volumes and key elevations (see Exhibit A) such as the lowpoint of the “would be” spillway of Sweetwater, which is the road crossing the outlet culvert. Hydrology Re-Calc As noted, the Streamstats hydrology, while we generally agree with the calculation procedure, does not take into account Sweetwater Lake itself. Sweetwater is a lake of approximately 70+ surface acres at normal pool elevation of approximately 7700 feet MSL (NAVD 88) with a natural channel and large, 137” x 91” CMP outlet pipe. There are no gates or weirs, neither is there a constructed spillway. It would seem, and the modeling suggests, that the outlet structure being so large is designed to allow large flows through and attenuate the lake without use of a spillway. While Sweetwater is not jurisdictional, the State Engineer’s Office does have it listed as Dam ID 530130 with dam parameters such as an outfall pipe (mis-identified as a 96” RCP) and a spillway (likely just referencing the natural berm of the downstream side of the lake). The CMP outlet pipe has free discharge as the flowline is a few feet above the downstream creek elevation. The spillway, essentially the access road, is at least 12 feet above the flowline out of the outlet pipe. As you will see in our analysis, that spillway is not reached in the design storm volumes. We processed the Streamstats basins as before in the following general manner. We calculated the overall basin to the 4730 parcel, then calculated the basin to the Sweetwater Lake outlet location. After this, and noting the surface types provided by SS, we then subtracted out the remaining basin below the lake to the 4730 address for input as the West Sheep Creek Basin. Then, with that basin delineated, we assessed another Streamstats for the longest time of concentration path, which would appear to be the West Sheep Creek Branch. That branch enters the main Sweetwater Creek approximately 3000 feet above the 4730 site. This then gives us reasonable assurance of “apples and apples” in basin analyses, adhering to the Streamstats data and applying this in the Hydrocad, TR-20 based software with NOAA hydrographs as the NOAA hydrologic data tends to be more accurate with real storm input (http://hdsc.nws.noaa.gov/hdsc/pdfs/). Therefore, we have utilized established Tc’s, surface types, field checked the outlet scenario for the lake, and provided a reasonable estimation of lake volumes for the attenuation impact using USGS data. The resultant is that the impact of the lake significantly reduces the 100-year flood flow through the site. The 100-year base 1920 cfs from Streamstats without Sweetwater is reduced to 810 cfs with the lake. As noted in the output, this is a 79% attenuation with a 670 minute-plus lag time. The peak storage elevation is 5.75 feet above normal outflow, a good seven feet below the road/spillway. Appendix A are the various Streamstats Output files. Appendix B is the HydroCAD Tr-20 output. Updated (SGM) Model That additional topography acquired includes the stream channel and the neighboring small pond with associated pond dike on the road (north) side of the creek. The south side is native steep slopes. Our goal is for no minimal downstream impact or making necessary improvements on the neighboring property to protect their structures. This includes both existing and proposed flood conditions downstream, along with a comfort level for stream velocities and continued dike protection. Using the above hydrologic data, we assembled the RAS model with similar Manning’s of 0.05 for a cobbly channel and 0.07 for flood fringe areas with light trees and brush. The reduced flow with Sweetwater Lake keep the floodplain within the main channel banks. From this, we do not need to do a floodway analysis as our impacts do not impact the floodplain in the first place. Just downstream of the proposed bridge site the channel curves to the right with a dike on the downstream left bank. That dike protects the neighboring pond and keeps the flow channelized. To better reflect this, we established ineffective flow areas on these lower cross sections for that pond area that, even if it had water, would not carry flow at any significant velocity. The resultant is that downstream impacts are negated. Our installation of the bridge does not impact the main channel, Cross section 4+55.77 (interpolated) is deleted and replaced by the bridge crossing, which re-interpolates the immediate upstream and downstream cross sections through. With this amendment, there is no rise downstream. Cross section 4+25 (interpolated and very near the property corner) indicates matching existing conditions and that continues as flows pass down the creek. Appendix C is the existing conditions RAS model, and Appendix D, the proposed conditions. We have highlighted the impacted cross sections on the existing and proposed RAS table output. Proposed Bridge The applicant is providing for a clear span bridge of approximately 40 feet (noted on the flood map, Exhibit C), with concrete abutments. It is anticipated that much of the abutment work, with the span being so long, affords us the ability to keep much of the impact outside the main channel with only minor rip-rap and minimize disturbance in the creek channel. The main channel will be largely untouched as we span, bank to bank. To establish the girder elevation we assess the typical debris flow to establish a freeboard using the common CDOT Drainage Design Manual equation noted below: Freeboard (ft) = 0.1 (Q^0.3) + 0.008 (V)^2. With Q set at 810 cfs, and the model indicating a velocity at the bridge of 7.58 fps, we get resultant freeboard of 1.21 feet. This then is added to the WSEL approximately 50 feet upstream. That elevation, at approximately Station 5+05 calculates at 6815.85 + 1.21 feet = 6817.06. Therefore we set the bottom of girder at 6817.1. The WSEL at the upstream bridge section for the proposed condition model is 6814.99 (see actual XS, interpolated from table). Therefore we have 17.1 – 14.99 = 2.11 feet of clearance from the 100-year WSEL to the bottom of girder satisfying the Eagle County and CWCB requirement for a minimum 2 feet of freeboard. Floodway / Site Condition With the indicated flows and model results, a floodway analysis isn’t needed as the current anticipated impacts do not warrant an encroachment onto the floodplain width. However, if such an exercise is needed, we have the 18” clear space for the bridge to allow for some level of WSEL rise should an encroachment be conducted. General commentary on the RAS model warnings As is often the case the calculations trigger cautions. The initial model noted, understandably so, cautions for critical flows and rapid drop in head, as may be expected from a steeper mountain stream. The recommended solution was adding interpolated cross sections. We did so to avoid many of these warnings, setting a maximum XS distance of 15 feet, but noted the results were no different, although many of those cautions went away. Therefore we did not add further cross sections as the warnings are triggers when calculation differences between cross sections are a note of calculations having a rapid change, but not necessarily an error or problem with the model. Please do not hesitate to contact me for any questions. Very Truly Yours, SGM Rick L Barth, Colorado PE 36749 Senior Engineer II, Civil Services Team Attachments: Exhibit A: LiDAR Topographic Map of Sweetwater and estimated volumes Exhibit B: Several photos of 4730 and the Lake Exhibit C: Site floodplain map (4730) Appendix A: Streamstats Output files Overall Basin Basin to Lake Basin Differential Calculation Basin downstream of Lake with longest Tc Appendix B: HydroCAD TR-20 Output for 2 and 100 year Appendix C: HecRAS Existing Conditions Model (named: Existing) Appendix D: HecRAS Proposed Conditions Model (named: Proposed 4) Exhibit A: LiDAR Topographic Map of Sweetwater Lake Graphic ScaleIn Feet: 1" = 300'0150300600Title:Map ofSweetwater LakeRevision#Dwg No.4730 Sweetwater Creek Road Eagle County, COJob No.Drawn by:Date:File:PE:QC:2020-589RLB2/25/21RLBAchen-BM--118 West Sixth Street, Suite 200 Glenwood Springs, CO 81601 970.945.1004 www.sgm-inc.com Date By:EX A 18Of :Not for ConstructionProject Milestone: Exhibit B: Photos of Lake and 4730 Site The “rickety” bridge near the east end of the 4730 Site. Looking from the north side of the creek to the southwest. You can see a bit of the existing cabin in the background. (Nov 28) From existing bridge looking upstream at creek geometry and vegetation cover. (Nov 28) Upstream side of Outlet at Sweetwater Lake (Feb 7) Downstream Outlet at Lake and “spillway” of the existing road (Feb 7) Exhibit C: 4730 Site Flood Map Graphic ScaleIn Feet: 1" = 30'0153060Title:4730 SiteFlood MapRevision#Dwg No.4730 Sweetwater Creek Road Eagle County, COJob No.Drawn by:Date:File:PE:QC:2020-589RLB2/25/21RLBAchen-BM--118 West Sixth Street, Suite 200 Glenwood Springs, CO 81601 970.945.1004 www.sgm-inc.com Date By:EX C 18Of :Not for ConstructionProject Milestone: Graphic Scale In Feet: 1" = 10' 0 5 10 20 118 West Sixth Street, Suite 200 Glenwood Springs, CO 81601 970.945.1004 www.sgm-inc.com Engineer: Drawn By: Sheet Subset: MCF MCF Structure Numbers BRIDGE GENERAL LAYOUT 4730 SWEETWATER ROAD (ACHEN RESIDENCE) -- of -- Project No./Code - - - Sheet Number No Revisions: Revised: Void: As Constructed Drawing File Name: GenLayout Date Comments Init.Rev. Sheet RevisionsComputer File Information Print Date: 5/3/21 Last Modification Date: 5/3/21 MCF Autocad Ver. 2018 SGM Project No.: 2020-589.001 Scale: As Shown Quality Control:Subset Sheets: Corporate Office: 7108 South Alton Way, Building B • Centennial, CO 80112 Locations: Centennial • Frederick • Silverthorne • Salida/Crested Butte Phone 303-220-0300 • www.cesareinc.com June 12, 2020 Ms. Robin Dunn 112 Stanley Run Buena Vista, CO 81211 Rmdunn12345@gmail.com Subject: Geologic Hazards Assessment 4730 Sweetwater Road Eagle County, Colorado Project No. 20.5027 Dear Ms. Dunn: Cesare, Inc. (Cesare) addresses the geologic hazards for Ms. Robin Dunn (Client) for the parcel located at 4730 Sweetwater Road in Eagle County, Colorado. Vicinity of the site is shown in Exhibit 1. EXHIBIT 1. Vicinity of 4730 Sweetwater Road in Eagle County, Colorado. Summary of conclusions: 1. The geologic hazards noted on the parcel are rockfall, landslides, and flooding. 2. The rockfall hazard is minimal from the outcrops that are on the property. There are no outcrops or sources for rockfall above the property. 3. The landslide hazard is low to moderate from the steep slope on the southern edge of the CESARE, INC. 20.5027 4730 Sweetwater Road Letter 06.12.20 2 property. Evidence of recent shallow slope movement was observed. Slope instability in the form of slumping and creep was noted. 4. The flooding hazard is defined by Eagle County and FEMA, and portions of the property are mapped within the flood hazard zone. 1. SCOPE A site visit was conducted by Cesare on May 19, 2020 to assess the geologic hazards that may impact the property and offer recommendations for additional work to reduce uncertainties in interpretation. The parcel is about 7 acres in size and is bisected by Sweetwater Creek. The driveway, garage, and cabin exist north of Sweetwater Creek. A pedestrian bridge crosses the creek and provides access to the residence on the southern side of the property. The structures exist on a flat alluvial terrace on either side of the creek. South of the residence the slope is steep, with slopes ranging from 2 horizontal to 1 vertical (2:1), to vertical in the areas where bedrock outcrops on site. This assessment addresses geologic hazards consistent with Colorado Senate Bill 35 (1972), House Bill 1041 (1974), and Eagle Country land use code requirements that could impact the site development. 2. SITE CONDITIONS The property is located approximately 8 miles north from the intersection of Interstate 70 and Colorado River Road in Dotsero, Colorado and another 4.5 miles northwest from the intersection of Colorado River Road and Sweetwater Road. The property is located on the south side of Sweetwater Road. The Sweetwater Creek canyon area is geologically mapped as Paleozoic sedimentary rocks, including the Leadville Limestone, Minturn, and Belden Formations1. The southern side of the canyon is mapped as having large Pleistocene landslides, and near the river channel the geology is mapped as recent alluvium, terrace deposits, and debris flow deposits 1. The property site morphology is a steep and north facing slope on the southern side, with a slope break to nearly 200 linear feet of flat ground at the base of the slope, bisected by the creek flowing west to east. There are two prominent rock outcroppings that form cliff faces on the property; one directly behind the residence and one upstream on the western edge of the property. These outcrops are Leadville Limestone bedrock. The property and slopes above are vegetated with conifers, oaks, shrubs, and grasses. The north facing aspect of the slope, and proximity to the creek, allows for large trees and significant vegetation cover. 3. HAZARDS ASSESSMENT 3.1 ROCKFALL HAZARD ASSESSMENT During the May 19, 2020 site visit, the Cesare engineering geologist inspected the current building sites, rock outcroppings, and the slope on the southern edge of the property. Two nearly vertical rock outcrops of Leadville Limestone exist onsite. One outcrop is directly behind (south) of the existing residence and is about 8 to 10 feet in height. The other outcrop is about 120 feet to the west 1 1Geologic Map of the Dotsero Quadrangle, Garfield and Eagle Counties, Colorado, 2008, Streufert, R.K., Kirkham, R.M., Schroeder, T.J., II, and Widmann, B.L., Colorado Geological Survey Open-File Report OF08-14. CESARE, INC. 20.5027 4730 Sweetwater Road Letter 06.12.20 3 of the home along the creek channel and is 20 to 40 feet in height (Exhibit 2). Both outcrops are described as massive, meaning there are few fracture sets in the rock mass. The fracture sets are widely spaced and discontinuous. The smaller outcrop behind the residence is covered in lichen and vegetation. Evidence of weathering was noted along the fractures in the large outcrop to the west, and fresher surfaces indicate that rocks have dislodged from the rockface. Boulders immediately below the rockface were 2.5 to 3 feet along their long axis, and were covered with soil and vegetation. Rocks present on the flat terrace of the site are interpreted to be transported colluvium from the hillslope above and alluvium from the creek. EXHIBIT 2. Rock outcrops consisting of Leadville Limestone. Left; the outcrop behind the residence. Right; the outcrop west along the creek. 3.2 LANDSLIDE HAZARDS ASSESSMENT The slope on the southern edge of the property is steep with slopes ranging from 2:1 to near vertical. The slope is vegetated with large trees shrubs and grasses. There is one main swale where drainage from above is directed, although there is no established surface stream channel in this zone. Below the swale area on the flat topography of the terrace there is a hummocky deposit that indicates slope material has slid from this area. Observations of the slope behind the residence and above the property boundary were conducted. Evidence of surficial sloughing, small slumps, and creep were noted (Exhibit 3). Active sloughing and colluvial movement were observed in the area directly behind the residence and the root cellar. The slope behind the residence has several vertical to near vertical arcuate scarps ranging from 2 feet to 8 feet in height. Slump block morphologies with back tilted areas below the scarps were noted. Pistol butted trees and tilted fenceposts, evidence of downslope movement over time, were found across the slope. CESARE, INC. 20.5027 4730 Sweetwater Road Letter 06.12.20 4 EXHIBIT 3. A) Sloughing of colluvium at the base of the slope behind the residence, B) Typical slump scarp/vertical offset on hillslope behind the residence, C) Back-rotated slump block below scarp in B, D) Tilted fenceposts and pistol butted trees common on the slope. A B C D CESARE, INC. 20.5027 4730 Sweetwater Road Letter 06.12.20 5 3.3 FLOODING HAZARD ASSESSMENT The parcel is mapped as being mostly inside the 100-year floodplain for Sweetwater Creek (Exhibit 4). The flat area on the property is a result of alluvial processes, and flood deposits are noted on the terrace surface. EXHIBIT 4. Map of the 100-year floodplain for Sweetwater Creek at 4730 Sweetwater Road. 3.4 OBSERVATIONS AND RECOMMENDATIONS Based on the size and nature of the rock outcrops onsite, this parcel has a low risk of rockfall impacting future development on the property. Rockfall from the outcrop to the west would be the most hazardous; however, with occasional monitoring for loose blocks, hand scaling of the rockface would be sufficient to minimize the risk to people and property. If vegetation conditions on the rockface or above the outcrop were to change significantly, a reassessment of the rockfall hazard would be warranted. The slope south of the property is mapped as a large Pleistocene age landslide. The conditions that existed to initiate this large mass movement no longer exist, and therefore, the larger landslide mass is considered relict. the steepness of the slope and the nature of the landslide material as overburden on the slope; however, creates conditions for shallow land slips, sloughing, creep, and smaller rotational slide events. It is likely that these events are triggered by increased moisture in the slope during spring snowmelt, or times of increased moisture due to intense thunderstorms or longer duration rain events. The downslope movement of material can impact new building or development CESARE, INC. 20.5027 4730 Sweetwater Road Letter 06.12.20 6 on the site. Slope stability measures should be assessed to protect any new development. These measures could include: measuring the thickness and characterizing the geological engineering properties of the overburden on the slope; increasing or modifying drainage in the slope to direct water away from unstable areas, such as wick drains in the slope, or a catchment/diversion ditch above the slope; or could also take the form of slope modifications to reduce the slope angle with a step pattern and/or the creation of rock retaining walls. It is recommended that any modification to the slope or additional building onsite be preceded by a slope stability analysis and professional evaluation of possible geologic engineering structures to increase slope stability. Because of the parcel’s location along Sweetwater Creek and that the existing buildings were built on the alluvial terraces, there is a flood hazard on the property. Floodplain development permits must be acquired from Eagle County for development in a designated floodplain. Development is defined as any construction or activity that changes the basic character, use, or topography of the land on which the construction or activity occurs, including but not limited to, any manmade change to improved or unimproved real estate, construction, or substantial improvement of building or other structures, mining, dredging, filling, grading, paving, excavating, or drilling operations of dam, wall, embankment, levee, dike, pile, abutment, projection, excavation, channel rectification, bridge, culvert, fence, encroachment or alteration located within the area of special flood hazard. Any work within the floodplain requires a “Floodplain Permit Application” and a checklist. This requirement is mandated by the Federal Emergency Management Agency for Eagle County to participate in the National Flood Insurance Program. Eagle County must comply with these requirements for residents and businesses to obtain flood insurance (https://www.eaglecounty.us/Engineering/Permits/). 4. CONCLUSIONS Cesare’s engineering geologist concluded that the rockfall hazard from the outcrops onsite is minimal. Rockfall hazard and risk can be mitigated with monitoring the rockfaces for loose material that can be scaled by hand. The slope on the property is actively moving by shallow creep, small rotational slides, and slope wash/slough. These downslope movements are likely triggered by increased moisture in the slope. It is recommended that the slope stability be assessed before new development is undertaken onsite. 5. LIMITATIONS This letter has been prepared for the exclusive use of our Client for specific application to the project discussed and has been prepared in accordance with generally accepted geologic and geotechnical engineering practices. No warranties, either expressed or implied, are intended or made. In the event that changes in the nature, design, or location of the project as outlined in this letter are planned, the conclusions and recommendations contained in this letter shall not be considered valid unless CESARE, INC. 20.5027 4730 Sweetwater Road Letter 06.12.20 7 Cesare reviews the changes and either verifies or modifies the conclusions of this letter in writing. Please contact Cesare with any questions or comments regarding this information. Sincerely, CESARE, INC. Holly Brunkal, PhD Darin R. Duran, P.E. Staff Engineering Geologist Principal, Manager - Salida and Crested Butte HAB/ksm 06/12/2020 5/9/22, 3:50 PM Eagle County Government Mail - old septic info for 4730 Sweetwater Road https://mail.google.com/mail/u/0/?ik=da50768ddd&view=pt&search=all&permmsgid=msg-a%3Ar4393812461817643302&simpl=msg-a%3Ar43938124…1/1 Claire Lewandowski <claire.lewandowski@eaglecounty.us> old septic info for 4730 Sweetwater Road Claire Lewandowski <claire.lewandowski@eaglecounty.us>Mon, May 9, 2022 at 3:50 PM To: Luiza <luiza@lkpeng.com> Cc: Danielle Salinsky <danielle.salinsky@eaglecounty.us>, "ECPHE (environment@eaglecounty.us)" <environment@eaglecounty.us> Thank you, Luiza! I am reviewing this in concurrence with the stream setback variance submitted to the EC Community Development Department. In that application there is a geohazard and floodplain report, see attached. It shows the OWTS within the 100 year floodplain, in which case the FEMA emergency standards must be addressed as required in Reg 43. Also can you address whether there are geohazard concerns due to slope stability? Here are more details on what Reg 43 states and what I can gather from FEMA: If the OWTS is to be located within that area it must be shown that there is no other more suitable location. OWTS installed in a 100-year floodplain must meet or exceed the requirements of the Federal Emergency Management Agency, this may include addressing tank buoyancy concerns and storage of wastewater in the event it cannot be discharged to the soil treatment area due to saturation. The system as approved by the ECPHA must be designed to minimize or eliminate infiltration of floodwaters into the system and discharge from the system into the floodwaters. The OWTS must be located to avoid impairment to floodwaters or contamination from them during flooding. Reg 43. local emergency management concerns must also be addressed; Eagle County requires that they participate in the National Flood Insurance Program. Thanks, again. Let me know if you have additional questions or concerns. Claire Lewandowski, REHS Environmental Health Specialist III she | her | hers 970-328-8755 (office) 970-328-8747 (direct) environment@eaglecounty.us www.eaglecounty.us Located on the lands of Arapahoe, Cheyenne, Ute, and Očhéthi Šakówiŋ peoples. [Quoted text hidden] Geo and Flodplain Report- 4730SwtwtrVarApp.pdf 1647K Pump Selection for a Pressurized System - Single Family Residence Project 21-3574 Achen - 4730 Sweetwater Rd / 4-brm pressure pump Parameters Discharge Assembly Size Transport Length Transport Pipe Class Transport Line Size Distributing Valve Model 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 2.00 9 40 1.50 None 6.2 8.5 40 1.25 4 68 40 1.25 1/8 4 5 None 0 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 0.43 72 31.3 4 2.1 4.9 gpm gpm % fps Frictional Head Losses Loss through Discharge Loss in Transport Loss through Valve Loss in Manifold Loss in Laterals Loss through Flowmeter 'Add-on' Friction Losses 1.9 0.5 0.0 0.3 0.3 0.0 0.0 feet feet feet feet feet feet feet Pipe Volumes Vol of Transport Line Vol of Manifold Vol of Laterals per Zone Total Volume 0.9 0.7 21.1 22.7 gals gals gals gals Minimum Pump Requirements Design Flow Rate Total Dynamic Head 31.3 14.2 gpm feet 0 1020304050607080 0 20 40 60 80 100 120 140 160 Net Discharge (gpm) PumpData PF5005 High Head Effluent Pump 50 GPM, 1/2HP 115/230V 1Ø 60Hz, 200/230V 3Ø 60Hz Legend System Curve: Pump Curve: Pump Optimal Range: Operating Point: Design Point: Sand Gradation Analysis Spreadsheet GRADATION ANALYSIS TEST ENTER INFORMATION IN BLUE CELLS LABORATORY TEST REPORT DATA GRADATION RESULTS COMPARED TO PREFERRED AND SECONDARY SAND FILTER SPECIFICATIONS Parameter Value Units Preferred Sand Value Pass / Fail Preferred Sand Secondary Sand Value Pass / Fail Secondary Sand Laboratory Client: Location / Plant: Sample / Product: Sample Date: Lab Test Date: Job Number: SIEVE SIEVE OPENING IN MILLIMETERS PERCENT PASSING THRU SIEVE 3"75 100.0 1.5 37.5 100.0 3/4"19 100.0 3/8"9.5 100.0 No. 4 4.75 99.0 No. 8 2.36 89.0 No. 16 1.18 73.0 No. 30 0.6 47.0 No. 50 0.3 21.0 No. 100 0.15 5.0 No. 200 0.075 2.0 D60 - Diameter that 60 percent of the sample is finer than.0.89 millimeters Effective Size - D10 - Diameter that 10 percent of the sample is finer than.0.197 millimeters 0.25 to 0.60 0.15 to 0.60 PASS Uniformity Coefficient (D60 / D10)4.52 unitless ratio < or = 4.0 < or = 7.0 PASS Percent passing thru #200 Sieve 2.0 millimeters < or = 3 PASS < or = 3 PASS FAIL FAIL Diameter of Particle in MillimetersPercent Passing Sieve0 10 20 30 40 50 60 70 80 90 100 75 37.5 19 9.5 4.75 2.36 1.18 0.6 0.3 0.15 0.075 Plot of Gradaon Analysis Sand Gradation Analysis Spreadsheet H-20 TRAFFIC LOADINGCHANGE FORH-20 TRAFFICLOADINGH-20 TRAFFIC LOADINGCHANGE FORH-20 TRAFFICLOADINGDESIGN CALCULATIONSDESIGN LONG TERM ACCEPTANCE RATE RATE = 0.65 GPD/SFNUMBER OF BEDROOMS: 4MAXIMUM DAILY FLOW = QMAXQmax = (3 BEDROOMS X 2 PERSONS/BEDROOM + 1 BEDROOM X 1 PERSON/BEDROOM) X 75 GALLONS/PERSON/DAYQMAX = 525 GPDSEPTIC TANKV = 1000 GALLONS FOR 2 TO 3 BEDROOMS PLUS 250 GALLONS FOR EACH ADDITIONAL BEDROOMUSE 1500-GALLONS, H-20 TRAFFIC LOADING, THREE COMPARTMENTS, CONCRETE SEPTIC TANK WITH EFFLUENTFILTER, AND HIGH HEAD PUMP BY VALLEY PRECAST OR EQUIVALENT APPROVED BY THE ENGINEER.ABSORPTION AREABASED ON APPLICATION RATE:A = 525GPD/0.65GPD/S.F.A = 808S.F.QUICK 4 PLUS, STANDARD INFILTRATOR CHAMBER SYSTEM IN A BED CONFIGURATION CONSTRUCTED OVER 2FOOT OF UNLINED SAND FILTERSURFACE AREA OF ONE QUICK4, PLUS STANDARD INFILTRATOR CHAMBER = 12 S.F.USE 68 QUICK4, PLUS, STANDARD, INFILTRATOR CHAMBERS IN BED AS SHOWN ON THE PLAN.NOTES:1. BENDS IN THE BUILDING SEWER SHALL BE LIMITED TO 45 DEGREES.2. THE SEPTIC TANK SHALL BE INSTALLED LEVEL.3. THE TANK SHALL HAVE RISERS OVER EACH ACCESS MANHOLE AND ALL RISERS SHALL EXTEND TO ORABOVE FINAL GRADE.4. EACH RISER LEAD WILL HAVE A SECURE CLOSING MECHANISM, SUCH AS A LOCK, SPECIAL HEADED BOLTSOR SCREWS, OR SUFFICIENT WEIGHT TO PREVENT UNAUTHORIZED ACCESS.5.THE SEPTIC TANK AND ALL THE PIPING WILL BE BACKFILLED UP TO THE INVERTS PRIOR TO SCHEDULINGAN INSPECTION.6. THE BED WITH THE INFILTRATOR CHAMBERS SHALL BE INSTALLED LEVEL, ALONG THE CONTOUR.7. EXCAVATE TWELVE (12) FEET WIDE BED8. THE BOTTOM AND THE SIDEWALLS OF THE BED SHALL BE RAKED (IF NEEDED) TO ELIMINATE SMEARING.8. THE BED WILL BE EXCAVATED ADDITIONAL TWO FEET BELOW THE PROPOSED BOTTOM OF THEINFILTRATOR CHAMBERS FOR THE SAND FILTER PLACEMENT.9.THE CLASSIFICATION OF THE SAND TO BE USED IN THE BED OF THE SOIL TREATMENT AREA (STA) MUSTBE LESS THAN 30 DAYS OLD AND SUBMITTED TO THE ENGINEER PRIOR TO THE SAND FILL PLACEMENT.10. MARK A LINE ON THE BED EXCAVATION WALLS AT THE 2-FOOT DEPTH FROM THE BOTTOM WITH SPRAYPAINT BEFORE THE SAND PLACEMENT11. PLACE THE SEND FILTER IN THE PREPARED BED TO THE MARKED DEPTH12. ASSEMBLE AND INSTALL THE INFILTRATOR CHAMBERS IN THE BED ACCORDING TO THE MANUFACTURERSRECOMMENDATIONS.13. INSTALL THE PERFORATED PRESSURE DISTRIBUTION LATERALS ACCORDING TO THE MANUFACTURERSRECOMMENDATIONS.14. SCHEDULE INSPECTION OF THE SYSTEM AND A SQUIRT TEST OF THE LATERALS15. BACKFILL THE SIDEWALL AREA WITH NATIVE ON-SITE SOIL FOR PROPER SUPPORT.16. BACKFILL THE BED WITH A MINIMUM OF 12 INCHES OF TAMPED SOIL COVER.17. THE FINAL GRADING OVERT THE STA WILL PROVIDE FOR UNIFORM RUNOFF AWAY FROM THE SOILTREATMENT AREA, WITHOUT ALLOWING WATER TO PUDDLE ON TOP.18. AVOID VEHICLE TRAFFIC OVER THE SYSTEM.19. ALL INSTALLATIONS SHALL MEET THE RULES AND REGULATIONS OF THE EAGLE COUNTYENVIRONMENTAL HEALTH DEPARTMENT AND OWTS REG 43 EFFECTIVE AUGUST 24, 2018 .20.FOR THE INSPECTION OF THE SEPTIC SYSTEM - NOTIFY THE EAGLE COUNTY ENVIRONMENTAL HEALTHDEPARTMENT AND THE DESIGN ENGINEER A MINIMUM OF 48-HOURS PRIOR TO BACKFILLING ANY PART OFTHE SYSTEM TO SCHEDULE AN INSPECTION.USE PRESSURE DISTRIBUTION, WITH 2 FEET OF UNLINED SAND FILTER (SECONDARY SAND ASSUMED)LTAR OF THE RECEIVING SOIL FOR TL3 (TABLE 10-1) = 0.65GPD/SFxSOIL SAMPLE TAKEN FROM PROFILE HOLE # 1 AT 48-INCHES WAS CLASSIFIED AS TYPE 3, LTAR = 0.35 GPD/SFWITH >35% ROCK (>2MM) SANDY CLAY LOAM, R-1, OPTION 1xSOIL SAMPLE TAKEN FROM PROFILE HOLE # 2 AT 48-INCHES WAS CLASSIFIED AS TYPE 3, LTAR = 0.35 GPD/SFWITH <35% ROCK (>2MM) CLAY LOAMxPROFILE HOLE 3 HAD SIMILAR SOIL WITH PROFILE HOLE 1 BELOW THE FILL LAYER.1.0 TO 8 FEET BROWN, SANDY CLAYLOAM, SILTY, GRAVELLY WITHANGULAR COBBLES AND BOULDERSNO GROUND WATER ENCOUNTEREDDUG 2/22/20221.0 TO 4.5 FEET LIGHT BROWN, CLAYLOAM, SILTY, SANDY WITH ROOTS4.5 TO 7.5FEET BROWN, SANDY CLAYLOAM, SILTY, GRAVELLY WITHANGULAR COBBLES AND BOULDERSNO GROUND WATER ENCOUNTEREDDUG 2/22/2022DEBRIS, WIRE, PLYWOOD, TOPSOIL,SAND, ETC.4 TO 5 FEET TOPSOIL WITH ROOTS5 TO 8 FEET BROWN, SANDY CLAYLOAM, SILTY, GRAVELLY WITHANGULAR COBBLES AND BOULDERSNO GROUND WATER ENCOUNTEREDDUG 2/25/2022SQUIRT TEST OF THE RESIDUAL HEAD OF THE STA BED LATERALSREMOVE THE END CAPS OF THE FLUSHING ASSEMBLY IN ORDER TO FLUSH THE LATERALS CLEAN FROMANY DRILLING DEBRIS OR DIRT. DO NOT INSTALL THE LAST INFILTRATOR CHAMBER SO THAT THEPERFORATIONS ON THE LATERALS ARE OPEN IN ORDER TO RUN THE SQUIRT TEST FOR THEMEASUREMENT OF THE 5-FT RESIDUAL HEAD (+/-10%). THE PREPARATIONS FOR THE SQUIRT TEST MUSTBE READY FOR THE TEST TO BE DONE DURING THE FINAL INSPECTION.AFTER THE TEST, INSTALL THE LAST CHAMBER ON ALL ROWS.PUMP SELECTIONA DISCHARGE PUMP CAPABLE OF DELIVERING 31.3 GPM AGAINST 14.2 FEET OF TOTAL DYNAMIC HEADWILL BE USED. THE ELEVATIONS BETWEEN THE PUMP INVERT AND THE INVERT OF THE DISTRIBUTIONVALVE SHOULD BE FIELD VERIFIED AND REPORTED BACK TO THE ENGINEER.FOR THE DISCHARGE PUMP USE ORENCO, PF500511 HIGH HEAD EFFLUENT PUMP. THE PUMP DOSINGWILL BE ON DEMAND WITH 90 GALLONS PER DOSE.INFILTRATOR SYSTEMS INC.QUICK4 PLUS STANDARD CHAMBERTYPICAL BED DETAILSECTION VIEW(NOT TO SCALE)NATIVE BACKFILLTOPSOIL2'SAND FILTERPRIMARY ORSECONDARYPRESSUREDISTRIBUTIONLINES4-FT MAX.ESTABLISH VEGETATIVE COVER12-FTSAND FILL PLACEMENTPLACE THE SAND FILL MATERIAL IN THE EXCAVATED BED.THE FILTERING MATERIAL USED IN A SAND FILTER MUST BE CLEAN, COARSESAND, CLASSIFIED AS PRIMARY SAND OR SECONDARY SAND. THE ABOVEDESIGN WAS PREPARED BASED ON SECONDARY SAND.THE CLASSIFICATION OF THE SAND TO BE USED IN THE BED OF THE SOILTREATMENT AREA (STA) MUST BE LESS THAN 30 DAYS OLD AND SUBMITTEDTO THE ENGINEER PRIOR TO THE SAND FILL PLACEMENT.~13~13~16~17EXISTING2-BEDROOM CABIN/FUTURE 4-BRMRESIDENCECLEANOUTPROPOSEDINVin=6812'OWTS X-SECTION SKETCHN.T.S~8.5' END MANIFOLD1.25-INCH SCH40 PVCABOUT 9 FEET OF 1.5 INCH SCH40PVC TRANSPORT (EFFLUENT LINE)EL=6817'INVout=6811.75'ASSUMEDINVout =6812.3'ABOUT 13 FEET OF 4-INCHDIAMETER SDR35 PVC,BUILDING SEWER LINE (THEFIRST AND LAST 5 FEET AT2 TO 5% SLOPEGROUND ELEVATIONVARIES FROM THE UPPERSIDE TO THE LOWER SIDEOF THE STA BEDMANIFOLDINVin=6813.5'GROUND ELEVATION~6817'BOTTOM OF ALLINFILTRATORSAT =~6813'SAND FILTERPRIMARY ORSECONDARY12-FT2'1500 GALLONS, H-20 TRAFFIC LOADING,THREE COMPARTMENTS CONCRETESEPTIC TANK WITH EFFLUENT FILTERAND ORENCO PUMP ASSEMBLY BYVALLEY PRECAST OR EQUIVALENTSURVEY BYMATTHEW S. SLAGLESLAGLE SURVEY SERVICES(EFFECTIVE LENGTH)SIDE VIEWValve BoxBall ValveFLUSHING ASSEMBLYN.T.S.SweepingEllbowEndCapINFILTRATOR SYSTEMS INC.QUICK4 PLUS STANDARD CHAMBERPRODUCT SPECIFICATION(NOT TO SCALE)PRESSURIZED PIPE DRILLPOINTS LOCATIONS(2 PLACES)(EFFECTIVE LENGTH)TOP VIEWSIDE VIEWEND VIEWQUICK4 PLUS ALL-IN-ONE 12 END CAPINSPECTION PORTVENT CAPOPEN BOTTOMVENT CAPINSPECTION PORT4-INCH DIAMETERSDR35 WITHPERFORATIONS ONTHE BOTTOM 8-INCHES2'12"+ATTACH TOINFILTRATORWITH A RING ORSCREWSINSPECTION PORTN.T.S.FINISHEDGRADEOPEN BOTTOMPRESSURE DISTRIBUTIONLATERAL (TYP.)Valve BoxBall Valve6830683068306832683468246826682268606870 6840685068206822682468286826682068306840685068206820681068206820 SWEETWATER ROADNORTH6828 SWEETWATERCREEKPROF - 2PROF - 11500 GALLONS, H-20 TRAFFIC LOADING, THREECOMPARTMENTS CONCRETE SEPTIC TANK WITHEFFLUENT FILTER AND ORENCO PUMP ASSEMBLYBY VALLEY PRECAST OR EQUIVALENTABOUT 12 FEET OF 4-INCH DIAMETERSDR35 PVC, NEW BUILDING SEWERLINE (THE FIRST AND LAST 5 FEET TOBE AT 2 TO 5% SLOPEDRILL ONE 1/4-INCH HOLE AT THE INVERT OFTHE FAR END OF EACH LATERAL FOR DRAININGOF THE REMAINING EFFLUENT FROM THE PIPEBETWEEN DOSING AND PLACE A ROCK UNDERIT TO PREVENT EROSION (TYPICAL)ABOUT 9 FEET OF 1.5 INCH SCH40PVC TRANSPORT (EFFLUENT LINE)ASSUMEDINVout=6812.3'INVout=6811.75'INVin=6812'68.0'CLEANOUTFLUSHING ASSEMBLYTHROUGH THE END CAPSSEE DETAILINSPECTION PORT (TYPICAL IN THE FIRSTAND LAST INFILTRATOR CHAMBER OF EACHROW, INSTALLED IN THE OPENING OF THECAP OPPOSITE OF THE PRESSURE LINE~68 FEET OF 1.25-INCH SCH40 PVC LATERAL,PERFORATED WITH 1/8-INCH HOLES AT 4-FOOTINTERVALS AT THE TOP OF THE PIPE (TYPICAL)INVin=6813.5'END CAP (TYP)~ 8.5' END MANIFOLD,1.25 INCH DIAMETERSCH40 PVCSTA BED WITH FOUR ROWS OF 17INFILTRATOR CHAMBERS EACHQUICK 4 PLUS, STANDARDINFILTRATOR CHAMBER(TYPICAL)50.8'20.1'51.2'PROF - 37.8'6.6'APPROXIMATELOCATION OFNEW BRIDGETANK COVERSEL=6817'APPROXIMATELOCATION OF THEOLD SEPTIC SYSTEM100-FTWELLSETBACKLINEFROMSTATOWARDSFUTUREWELLTYPICAL FLUSHING ASSEMBLYAND INSPECTION PORTDRAWN BY:CHECKED BY:PROJECT NO.:SHEET:DRAWING NO.:DATE:BYDESCRIPTIONDATENO.L.P.L.P.C-121-3574MARCH 1, 202221-3574OWTS.DWGONSITE WASTEWATER TREATMENT SYSTEMMAJOR REPLACEMENTP.O. Box 724 EAGLE, CO 81631Tel (970) 390-0307www.LKPEngineering.comTRAVIS ACHEN RESIDENCEMAP~1"=3000'SITEPARCEL OF LAND IN SECTION 31, T3S, R86W, 6TH P.M.4730 SWEETWATER ROAD EAGLE COUNTY, COLORADOмͿйкͿлйлл