HomeMy WebLinkAbout263 Wolcott Springs Rd - 194127205002Environmental Health Department P.O. Box 179 500 Broadway Eagle, CO 81631-0179 Phone: (970) 328-8730 Fax: (970) 328-7185 Permit Permit No. OWTS-029340-2024 Permit Type: OWTS Permit Work Classification: New Permit Status: Final Issue Date: 11/19/2024 Expires: 5/5/2025 On-Site Wastewater Treatement System Project Address Parcel Number 117 WOLCOTT SPRINGS RD, WOLCOTT AREA,194127200047 Owner Information Address Richard Benes 12 Blackmer RD Englewood, CO 80113 Phone: (303) 962-2200 Cell: Email: rlb@cmc-group.com Inspections: For Inspections Call: (970) 328-8755 Engineer Phone Email Best Engineering Solutions and Technologies, Matthew Best (970) 409-9670 matt@bestengineeringusa .com Contractor License Number Phone Email Hill Builders, INC hillbuildersinc@gmail.com(970) 379-9545OWTSPL-000388-20 25 Permitted Construction / Details: Install the new system exactly as depicted in the Best Engineering design dated December 8th, 2023, revised, stamped and signed on November 15th, 2024 by Matthew A Best, PE. This system is designed to accommodate the maximum daily flows for a four bedroom residence. The OWTS consists of one sewer line from the residence. A Valley Precast, 1500 gallon, two-compartment, concrete septic tank equipped with an effluent filter in the outlet tee shall be used. A Tuf-Tite, 4 hole distribution box equipped with flow equalizers will be accessible at grade. The STA consists of four trenches of 13 Infiltrator Quick4 Plus Standard chambers for a total of 52. 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 dwelling. 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 Danielle Salinsky Date November 19, 2024 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 Friday, February 14, 2025 1 Inspection Result Eagle County, Colorado P.O. Box 179 500 Broadway Eagle, CO Phone: (970) 328-8730 Fax: (970) 328-7185 IVR Phone: 1-866-701-3307 Inspection Number: INSP-538271-2025 Permit Number: OWTS-029340-2024 Inspection Date: 12/06/2024 Inspector: Weems, Kirk Permit Type: OWTS Permit Inspection Type: OWTS Final Inspection Work Classification: NewOwner:Richard Benes Job Address:117 WOLCOTT SPRINGS RD IVR Pin Number:201529 WOLCOTT AREA, CO Project:<NONE> Parcel Number:194127200047 Contractor:Phone: (970) 379-9545 / Cell: (970) 379-9545Hill Builders, INC Inspection Status: Approved Inspection Notes Inspector Comments Added Item: Septic Tank 12/06/2024 - 1500 gal valley precast concrete tank. Added Item: Record Drawing 02/14/2025 - Use storm drain drawing submitted by Nathan Moffatt / Hill Builders Added Item: Record Photos Provided by inspector and Hill Builders Added Item: Site and Soil Included in revised design Added Item: Final Certification Letter received 02/14/2025 Added Item: General Plan generally installed according to plan. Changes were made in location of tank and STA. Storm drain structure passes over encased effluent line. See record photos and drawing. Added Item: Soil Treatment Area (STA) 12/06/2024 - 4 rows of 13 infiltrator quick 4 chambers; Tuff tite 4 hole distribution box Added Item: Identification of Systems Contractor 12/06/2024 - Hill Builders - Nathan Moffatt Friday, February 14, 2025 For more information visit: http://www.eaglecounty.us Page 1 of 2 Friday, February 14, 2025 For more information visit: http://www.eaglecounty.us Page 2 of 2 Environmental Health Department P.O. Box 179 500 Broadway Eagle, CO 81631-0179 Phone: (970) 328-8730 Fax: (970) 328-7185 Permit Permit No. OWTS-029340-2024 Permit Type: OWTS Permit Work Classification: New Permit Status: Active Issue Date: 11/19/2024 Expires: 5/5/2025 On-Site Wastewater Treatement System Project Address Parcel Number 117 WOLCOTT SPRINGS RD, WOLCOTT AREA,194127200047 Owner Information Address Richard Benes 12 Blackmer RD Englewood, CO 80113 Phone: (303) 962-2200 Cell: Email: rlb@cmc-group.com Inspections: For Inspections Call: (970) 328-8755 Engineer Phone Email Best Engineering Solutions and Technologies, Matthew Best (970) 409-9670 matt@bestengineeringusa .com Contractor License Number Phone Email Hill Builders, INC hillbuildersinc@gmail.com(970) 379-9545OWTSPL-000363-20 24 Permitted Construction / Details: Install the new system exactly as depicted in the Best Engineering design dated December 8th, 2023, revised, stamped and signed on November 15th, 2024 by Matthew A Best, PE. This system is designed to accommodate the maximum daily flows for a four bedroom residence. The OWTS consists of one sewer line from the residence. A Valley Precast, 1500 gallon, two-compartment, concrete septic tank equipped with an effluent filter in the outlet tee shall be used. A Tuf-Tite, 4 hole distribution box equipped with flow equalizers will be accessible at grade. The STA consists of four trenches of 13 Infiltrator Quick4 Plus Standard chambers for a total of 52. 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 dwelling. 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 Danielle Salinsky Date November 19, 2024 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, November 19, 2024 1 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com ONSITE WASTEWATER TREATMENT SYSTEM DESIGN 117 WOLCOTT SPRINGS ROAD WOLCOTT, COLORADO 81655 PROJECT NUMBER 22-1420 DECEMBER 8, 2023 REVISED MAY 15, 2024 PREPARED FOR RICHARD BENES 12 BLACKMER ROAD CHERRY HILLS VILLAGE, COLORADO 80113 Prepared By: Reviewed By: 5/15/2024 Nawal A. Obaid Matthew A. Best, P.E. Staff Engineer Project Engineer 117 Wolcott Springs Road Project Number: 22-1420 [2] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. Table of Contents PURPOSE AND SCOPE OF WORK ...................................................................................................................................................... 3 PROPOSED CONSTRUCTION.............................................................................................................................................................. 3 SITE CONDITIONS ................................................................................................................................................................................ 3 FIELD EXPLORATION ......................................................................................................................................................................... 3 SUBSURFACE CONDITIONS ............................................................................................................................................................... 3 OWTS ANALYSIS .................................................................................................................................................................................. 3 DESIGN RECOMMENDATIONS .......................................................................................................................................................... 4 HOMEOWNER PRECAUTIONS ........................................................................................................................................................... 5 LIMITATIONS ........................................................................................................................................................................................ 6 TABLE 1 – SUMMARY OF LABORATORY TEST RESULTS FIGURE 1 –SITE MAP FIGURE 2 – SITE PLAN AND SEPTIC SYSTEM AREA FIGURE 3 – TEST PIT LOGS FIGURE 4 – LEGEND AND NOTES FIGURE 5 – SEPTIC LAYOUT AND TEST PIT LOCATION FIGURE 6 – SOIL TREATMENT AREA DETAILS FIGURE 7 – SOIL TREATMENT AREA CALCULATIONS 117 Wolcott Springs Road Project Number: 22-1420 [3] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. PURPOSE AND SCOPE OF WORK This report presents the results of an onsite wastewater treatment system (OWTS) design for the project at 117 Wolcott Springs Road in Wolcott, Colorado. The purpose of this report is to provide design details for an OWTS in accordance with the 2018 Eagle County Onsite Wastewater Treatment System Regulations and the 2018 Colorado Department of Health and Environment Regulation Number 43. The project site is shown on Figure 1. Best Engineering Solutions and Technologies, LLC (BEST) conducted a subsurface exploration and provided foundation design recommendations in our Geotechnical Engineering Study report, dated November 11, 2022, and revised July 31, 2023. Please refer to this report for additional subsurface information. PROPOSED CONSTRUCTION We understand that the proposed residence will be a single-family home with an attached garage. The residence will have three bedrooms. The home will be conventional wood frame construction. If the number of bedrooms for the residence is different from what is described above, we should be notified to re-evaluate the recommendations contained in this report. SITE CONDITIONS At the time of our field exploration, the lot was vacant and was lightly covered with natural vegetation. The site is bounded by agricultural lands. The topography in the area slopes toward the north and east and is at an approximate ranging elevation of 7,815 to 7,821 feet MSL. FIELD EXPLORATION The field exploration was performed on October 21, 2022. The test pits were excavated approximately at the location shown on Figure 2 to evaluate the subsurface conditions. The test pits were excavated with a mini excavator and logged by a representative of BEST. Samples of the soils were taken with undisturbed sampling methods and the depths of the samples are shown on the Test Pit Logs, Figure 3 and Legend and Notes, Figure 4. SUBSURFACE CONDITIONS Test Pit TP-1 encountered silt loam to a depth of approximately 4 feet Below Existing Grade (BEG). Loam was encountered to the maximum depth explored of 7 feet BEG. Test Pit TP-2 encountered loam to a depth of approximately 5 feet BEG. Silt loam was encountered to the maximum depth explored of 8 feet BEG. Test Pit TP-3 encountered loam to the maximum depth explored of 6 feet BEG. Refusal was encountered in Test Pit TP- 3. Groundwater was not encountered during excavation of the test pits. Fluctuations in the groundwater levels may occur seasonally or with precipitation events. Samples taken from the exploratory test pits were retained for laboratory testing and inspected by the project engineer. The results of the tests performed on the samples obtained from the test pits are shown on Table 1. Laboratory testing included index property tests, such as moisture content and density, Atterberg limit test and gradation analysis. The testing was performed on bag samples obtained from the test pits. OWTS ANALYSIS We recommend a trench and infiltrator chamber system be used to provide effluent treatment from the proposed residence. The Soil Treatment Area (STA) was sized for a maximum of three bedrooms, Type 2 Loam with a Long-term acceptance rate (LTAR) of 0.60, and TL1. Calculations are provided in Figure 7. The effluent will gravity flow to the septic tank for primary treatment and will gravity flow to the STA for final treatment. 117 Wolcott Springs Road Project Number: 22-1420 [4] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. DESIGN RECOMMENDATIONS The design recommendations presented below are based on the proposed construction, the site, and subsurface conditions encountered and our experience in this area. If the conditions encountered during construction are different than those that are described in this report, please contact us and we will re-evaluate our design recommendations. SOIL TREATMENT AREA 1. The treatment system shall consist of four (4) trenches, each twelve (12) infiltration chambers long, see the table below. The trenches shall be a maximum width of 36-inches and shall be spaced at least 48 inches from trench wall to trench wall. The relative infiltration elevations shown on Figure 6 and provided in the table below are approximate and may need to be adjusted in the field to accommodate construction and actual elevation changes. 2. The chambers shall be Quick4 Plus Standard infiltrator chambers, or an approved equivalent. Chambers shall be installed in accordance with the manufacturer’s recommendations. 3. Topsoil within the proposed STA shall be stripped and removed prior to excavation of the trenches. 4. The maximum cut for the uphill side of the excavation to the infiltration surface shall be 4 feet from the ground surface. The bottom of the trench excavation should be scarified prior to chamber placement. 5. A minimum of 10 inches of cover soil should be placed over the chambers. The soil cover may consist of native soils. 6. Backfill should be graded to deflect surface water away from the STA and should be sloped at 3H:1V maximum. 7. Disturbed soil should be re-vegetated as soon as possible with a native grass seed mixture. No trees, shrubs, or other plants with deep roots should be planted on or near the STA as this may damage the system. 8. Four-inch diameter inspection ports should be installed vertically into the beginning and end of each trench. The inspection ports should extend at least 8 inches above the finished ground surface or be protected in a valve box at finished grade. The portion that lies within the gravel layer should be perforated. 9. A plan view of the STA is presented in Figure 5 with a cross section view presented on Figure 6. TABLE – TRENCH CHAMBER SCHEDULE Trench Number (West to East) Number of Chambers Trench Length (ft) Relative Infiltration Elevation (ft), Figure 6 Trench 1 12 48 7,820 Trench 2 12 48 7,821 Trench 3 12 48 7,823 Trench 4 12 48 7,824 OWTS COMPONENTS Recommended OWTS components provided below are based on our design details and our experience with the specific component manufacturers. Equivalent components may be feasible but need to be approved by us prior to construction. SEPTIC TANK 1. A 1,000 gallon, two-chamber, precast septic tank from valley precast, item #1000T-2CP3 or equivalent, is proposed for the OWTS. The first compartment must be at least 500 gallons. 2. The tank must be set level. The bottom of the excavation shall be free of large rocks or other objects that could damage the tank during placement. A gravel or road base bedding material may be necessary to prevent tank damage during placement and act as a leveling course. 117 Wolcott Springs Road Project Number: 22-1420 [5] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. 3. Install tank with 2 feet minimum cover soil for frost protection. Maximum soils cover depth is 4 feet or per manufacture’s recommendations. 4. The septic lids must extend to final surface grade and made to be easily located. 5. An effluent filter shall be located prior to the effluent piping to the STA. SEWER PIPE 1. The sewer line from the residence to the septic tank should not be less than the diameter of the building drain and not less than 4 inches in diameter. 2. A cleanout shall be located within 5 feet of the residence. If necessary, additional cleanouts are required every 100 feet of pipe and locations where the sewer pipe bends 90 degrees. 3. The sewer pipe should have a rating of SDR35 or better. The sewer pipe should be sloped between 2% and 4% to help limit disturbance of solids in the tank and potential sewage bypass of the first chamber of the tank. If a steeper slope is necessary, this can be accomplished with vertical step-downs in the sewer line, in the last 5 feet prior to the tank. 4. A minimum of 36 inches of cover soil should be provided over the sewer pipe. Paved areas, patios, or other areas without vegetative cover may be more susceptible to frost. We recommend a minimum of 48 inches of soil cover over the sewer pipe in these areas and the pipe be insulated on top and sides with 2- inch think blue foam insulation board. If adequate soil cover is not possible, we should be contacted for re-evaluation prior to construction. 5. The sewer pipe should be bedded in compacted ¾-inch road base or native soils provided that the native soils contain no angular rocks or rocks larger that 2.5-inches in diameter to help prevent settlement of the pipe. Sags could cause standing effluent to freeze and damage piping. 6. All 90-degree bends should be installed using a 90-degree long sweep or by using two 45-degree elbows. 7. The sewer line location shown on Figure 5 is considered conceptual. We assume that there will be only one sewer line exiting the residence. It is the responsibility of the owner to locate all sewer line exit locations and connections to the septic tank. We should be notified if there are other sewer lines exiting the residences. EFFLUENT TRANSPORT PIPING 1. We recommend 3-inch diameter SDR35 effluent transport piping. 2. The effluent transport pipe should be bedded in compacted ¾-inch road base or native soils, provided that the native soils contain no angular rocks or rocks larger than 2.5-inches in diameter to help prevent settlement of the pipe. Sags could cause standing effluent to freeze and damage piping. 3. A minimum of 18-inches of cover soil should be provided over the effluent transport pipe. Paved areas, patios, or other areas without vegetative cover may be more susceptible to frost. We recommend a minimum of 48 inches of soil cover over the sewer pipe in these areas and the pipe be insulated on top and sides with 2-inch thick blue foam insulation board. If adequate soil cover is not possible, we should be contacted for re-evaluation prior to construction. 4. The effluent pipe should be double encased with a larger diameter SDR35 pipe underneath driveway surfaces and be provided with a minimum of 48 inches of soil cover and be insulated on top and sides with 2-inch thick foam insulation board. 5. All 90-degree bends should be installed using a 90-degree long sweep or by using two 45-degree elbows. 6. The distribution box should be a Tuf-Tite 4-hole distribution box, or equivalent. Flow equalizers must be used to adjust the flow between the laterals. The levels and the distribution box should be installed per the manufacturer’s instruction. HOMEOWNER PRECAUTIONS The OWTS will require periodic inspection and maintenance to function properly. A properly designed, installed, and maintained system can greatly increase its lifespan. The level of maintenance will vary depending on the 117 Wolcott Springs Road Project Number: 22-1420 [6] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. complexity of the system and water use habits of the residents. Below are some basic recommendations for the OWTS operation and maintenance. HOUSEHOLD RECOMMENDATIONS 1. Use of a kitchen garbage disposal is not recommended. If garbage disposal is utilized, kitchen wastewater should be screened thoroughly. Many kitchen solids are not decomposed in the septic tank and may cause increase tank pumping frequency. 2. Water use should be monitored, and plumbing leaks fixed immediately as this may generate up to 1,000 gallons per day, which may flood the system and cause a hydraulic overload of the STA. 3. Use of high efficiency water fixtures is recommended to decrease the hydraulic load on the OWTS system. 4. Do not irrigate the area on top of or directly adjacent to the STA as this may cause a hydraulic overload of the STA. 5. Do not dispose of household waste down household drains as this may clog or damage the OWTS components. Examples of household waste include, but is not limited to: dental floss, cotton swabs, coffee grounds, paper towels, feminine products, and many other kitchen or bath items, etc. 6. Do not dispose of household chemicals, greases, oils, paints, hot tub water, or water softener brine in household drains. A separate drywell, if feasible, may be necessary for hot tub water or water softener brine disposal. 7. Limit the use of bleach as this may harm the useful bacteria in the septic tank and STA. 8. Liquid dishwasher and clothes detergent is recommended for households using OWTS. Clay substances used as fillers in powder detergents may result in clogging of the STA. MAINTENANCE 1. The effluent in septic tanks can freeze during extended period of non-use in cold weather. We recommend that a tank heater be installed in this system to help prevent freezing. 2. Inspect the septic tank, pump vault filter, treatment system, and soil treatment area at least annually for problems or signs of failure. 3. The pump vault filter should be cleaned annually by spray washing solids into the first chamber of the septic tank. 4. The septic tank should be pumped and cleaned every 3 to 5 years depending on use. Longer pumping intervals may increase the amount of solids that reach the soil treatment area, which may shorten the life span. 5. Pumping of the septic tank should take place when the level of the sludge and scum layers combined take up 25 to 33% of the capacity of the first chamber of the tank. LIMITATIONS This study has been conducted in accordance with generally accepted engineering practices in this area for exclusive use by the client for design purposes. Copying of this report or portions of this report without the express written permission of Best Engineering Solutions and Technologies, LLC (BEST), is specifically prohibited. We make no warranty either express or implied. The conclusions and recommendations submitted in this report are based upon data obtained from the exploratory test pits at the locations indicated on Figures 2 and 5, soil texture analysis, and the proposed construction. This report may not reflect subsurface variations that occur between the explorations. The nature and extent of variations across the site may not become evident until site grading and excavations are performed. If fill, soil, rock or water conditions appear to be different from those described herein, BEST should be advised at once so that a re-evaluation of the recommendations presented in this report can be made. BEST is not responsible for liability associated with interpretation of subsurface data by others. 117 Wolcott Springs Road Project Number: 22-1420 [7] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. It is our opinion that the designed location of the OWTS components does not violate any setback requirements of the current Eagle County Regulations. Below is a table of common minimum horizontal setbacks to OWTS components. Refer to the Eagle County Regulations for a complete list of required setbacks. We recommend that OWTS components be surveyed by a Professional Land surveyor licensed in Colorado and verified by BEST prior to the system permitting. TABLE 1 – COMMON MINIMUM HORIZONTAL SETBACKS FROM OWTS COMPONENTS Wells Water Supply Line Occupied Dwelling with Basement Property Lines, or Lined Ditch Lake, Irrigation Ditch, Stream, Wetland Dry Ditch, Gulch, or Cut Bank Septic Tank Absorption Trenches 100’ 25’ 20’ 10’ 50’ 25’ 5’ Septic Tank 50’ 10’ 5’ 10’ 50’ 10’ - Building Sewer Lines 50’ 5’ 0’ 10’ 50’ 10’ - Matthew A. Best, P.E. Project Engineer B.E.S.T. 192 13922-1420TP-1 1.5-4 AS06 33 16 7 17 76 Silt loamTP-1 6 HD 4 41 55 SW= 4.5 WSS= 20.0 LoamTP-2 2-5 AS06 341610 21 69 LoamTP-2 5-8 AS07 28 16 5 19 76 Silt loamTP-3 1.5-6 AS0538205 31 64 LoamTABLE: 1 Page 1 of 1AS=Auger SampleST=Shelby TubeHD=Hand DriveC4=Pocket ValueSS=Split Spoon SampleGeoadmin@BestEngineeringUSA.com Address: 1393 South Inca Street, Denver, Colorado 80223 ● Psalm 20 ● Phone: 303-238-1770WSS=Water Soluble SulfatesRA=Radon Testing (pCi/L)pH = pH of soilAD=Air DriedCA=California SampleRM=Remolded SampleOR = Organic content of soilAdditional Test Results (Note 3)CT=Consolidation TestATTERBERG LIMITS% Swell and Consolidation% Sand -No. 4 +No. 200% Fines -No. 200C2=Miniature CompressionC3=Pocket PenetrometerNOTE 2-Shear Strength TestsSoil DescriptionNOTE 3- Additional Test ResultsTT=Triaxial TestPT=ProctorC1= Unconfined Compressionhttps://bestengineeringusa.sharepoint.com/Shared Documents/Projects/22-1000 Summit Projects/22-1420 117 Wolcott Springs Road/Calcs/Septic/[22-1420 117 TABLE 1.1SUMMARY OF LABORATORY TEST RESULTSPROJECT:LOCATION: SOURCE:PROJECT NO:Field Test Boring / Lab TestingDATE:117 Wolcott Springs RoadWolcott, COMay 15, 2024Boring No.BS=Bag SampleNat. Dry Density (PCF)Natural Moist. (%)GRADATIONLL PIDepth Sample Type (Note 1)NOTE 1- Sample Type% Gravel +No. 4 B.E.S.T. 22-1420SITE MAP Project Number Figure 1Geoadmin@BestEngineeringUSA.com Address: 1393 South Inca Street, Denver, Colorado 80223 ● Psalm 20 ● Phone: 303-238-1770NNot to Scale Physical Address: 1393 South Inca Street, Denver, Colorado  Psalm 20  Phone: 303-238-1770  Office@BestEngineeringUSA.com December 9, 2024 Dick Benes 12 Blackmer Road Cherry Hills Village, Colorado 80113 Subject: Septic Installation Observation 263 Wolcott Springs Road Wolcott, Colorado 81655 Project No. 24-2166 At your request, Best Engineering Solutions and Technologies, LLC (BEST) visited the subject site on December 5, 2024, to provide observations during the onsite wastewater treatment system installation. We used information from our Onsite Wastewater Treatment System Design report, dated December 8, 2023, revised May 15, 2024, project number 22-1420. Our observations and recommendations are presented below. The onsite wastewater treatment system was consistent with the design, as shown in our report, which is listed above. During our site visit, the tank, pipes, and the soil treatment area were installed in general conformance with standard construction practices and our design. No deviations from our report are necessary. Our observations and recommendations submitted in this report are based on the conditions observed during our site visit. Best Engineering Solutions and Technologies LLC is not responsible for liability associated with construction defects contrary to the recommendations in our design report. If you have any questions regarding this report, please contact us. Respectfully submitted, BEST ENGINEERING Matthew A. Best, P.E. 12/9/2024 Principal Engineer 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com ONSITE WASTEWATER TREATMENT SYSTEM DESIGN 117 WOLCOTT SPRINGS ROAD WOLCOTT, COLORADO 81655 PROJECT NUMBER 22-1420 DECEMBER 8, 2023 REVISED NOVEMBER 15, 2024 PREPARED FOR RICHARD BENES 12 BLACKMER ROAD CHERRY HILLS VILLAGE, COLORADO 80113 Prepared By: Reviewed By: 11/15/24 Nawal A. Obaid Matthew A. Best, P.E. Staff Engineer Project Engineer 117 Wolcott Springs Road Project Number: 22-1420 [2] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. Table of Contents PURPOSE AND SCOPE OF WORK ...................................................................................................................................................... 3 PROPOSED CONSTRUCTION.............................................................................................................................................................. 3 SITE CONDITIONS ................................................................................................................................................................................ 3 FIELD EXPLORATION ......................................................................................................................................................................... 3 SUBSURFACE CONDITIONS ............................................................................................................................................................... 3 OWTS ANALYSIS .................................................................................................................................................................................. 3 DESIGN RECOMMENDATIONS .......................................................................................................................................................... 3 HOMEOWNER PRECAUTIONS ........................................................................................................................................................... 5 LIMITATIONS ........................................................................................................................................................................................ 6 TABLE 1 – SUMMARY OF LABORATORY TEST RESULTS FIGURE 1 –SITE MAP FIGURE 2 – SITE PLAN AND SEPTIC SYSTEM AREA FIGURE 3 – TEST PIT LOGS FIGURE 4 – LEGEND AND NOTES FIGURE 5 – SEPTIC LAYOUT AND TEST PIT LOCATION FIGURE 6 – SOIL TREATMENT AREA DETAILS FIGURE 7 – SOIL TREATMENT AREA CALCULATIONS 117 Wolcott Springs Road Project Number: 22-1420 [3] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. PURPOSE AND SCOPE OF WORK This report presents the results of an onsite wastewater treatment system (OWTS) design for the project at 117 Wolcott Springs Road in Wolcott, Colorado. The purpose of this report is to provide design details for an OWTS in accordance with the 2018 Eagle County Onsite Wastewater Treatment System Regulations and the 2018 Colorado Department of Health and Environment Regulation Number 43. The project site is shown on Figure 1. Best Engineering Solutions and Technologies, LLC (BEST) conducted a subsurface exploration and provided foundation design recommendations in our Geotechnical Engineering Study report, dated November 11, 2022, and revised July 31, 2023. Please refer to this report for additional subsurface information. PROPOSED CONSTRUCTION We understand that the proposed residence will be a single-family home with an attached garage. The residence will have four bedrooms. The home will be conventional wood frame construction. If the number of bedrooms for the residence is different from what is described above, we should be notified to re-evaluate the recommendations contained in this report. SITE CONDITIONS At the time of our field exploration, the lot was vacant and was lightly covered with natural vegetation. The site is bounded by agricultural lands. The topography in the area slopes toward the north and east and is at an approximate ranging elevation of 7,815 to 7,821 feet MSL. FIELD EXPLORATION The field exploration was performed on July 8, 2024. The test pits were excavated approximately at the location shown on Figure 2 to evaluate the subsurface conditions. The test pits were excavated with a mini excavator and logged by a representative of BEST. Samples of the soils were taken with undisturbed sampling methods and the depths of the samples are shown on the Test Pit Logs, Figure 3 and Legend and Notes, Figure 4. SUBSURFACE CONDITIONS Test Pit TP-1 encountered silt loam to a depth of approximately 4 feet Below Existing Grade (BEG). Loam was encountered to the maximum depth explored of 7 feet BEG. Test Pit TP-2 encountered loam to a depth of approximately 5 feet BEG. Silt loam was encountered to the maximum depth explored of 8 feet BEG. Test Pit TP-3 encountered loam to the maximum depth explored of 6 feet BEG. Refusal was encountered in Test Pit TP- 3. Groundwater was not encountered during excavation of the test pits. Fluctuations in the groundwater levels may occur seasonally or with precipitation events. Samples taken from the exploratory test pits were retained for laboratory testing and inspected by the project engineer. The results of the tests performed on the samples obtained from the test pits are shown on Table 1. Laboratory testing included index property tests, such as moisture content and density, Atterberg limit test and gradation analysis. The testing was performed on bag samples obtained from the test pits. OWTS ANALYSIS We recommend a trench and infiltrator chamber system be used to provide effluent treatment from the proposed residence. The Soil Treatment Area (STA) was sized for a maximum of three bedrooms, Type 2 Loam with a Long-term acceptance rate (LTAR) of 0.60, and TL1. Calculations are provided in Figure 7. The effluent will gravity flow to the septic tank for primary treatment and will gravity flow to the STA for final treatment. DESIGN RECOMMENDATIONS 117 Wolcott Springs Road Project Number: 22-1420 [4] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. The design recommendations presented below are based on the proposed construction, the site, and subsurface conditions encountered and our experience in this area. If the conditions encountered during construction are different than those that are described in this report, please contact us and we will re-evaluate our design recommendations. SOIL TREATMENT AREA 1. The treatment system shall consist of four (4) trenches, each thirteen (13) infiltration chambers long, see the table below. The trenches shall be a maximum width of 36-inches and shall be spaced at least 48 inches from trench wall to trench wall. The relative infiltration elevations shown on Figure 6 and provided in the table below are approximate and may need to be adjusted in the field to accommodate construction and actual elevation changes. 2. The chambers shall be Quick4 Plus Standard infiltrator chambers, or an approved equivalent. Chambers shall be installed in accordance with the manufacturer’s recommendations. 3. Topsoil within the proposed STA shall be stripped and removed prior to excavation of the trenches. 4. The maximum cut for the uphill side of the excavation to the infiltration surface shall be 4 feet from the ground surface. The bottom of the trench excavation should be scarified prior to chamber placement. 5. A minimum of 10 inches of cover soil should be placed over the chambers. The soil cover may consist of native soils. 6. Backfill should be graded to deflect surface water away from the STA and should be sloped at 3H:1V maximum. 7. Disturbed soil should be re-vegetated as soon as possible with a native grass seed mixture. No trees, shrubs, or other plants with deep roots should be planted on or near the STA as this may damage the system. 8. Four-inch diameter inspection ports should be installed vertically into the beginning and end of each trench. The inspection ports should extend at least 8 inches above the finished ground surface or be protected in a valve box at finished grade. The portion that lies within the gravel layer should be perforated. 9. A plan view of the STA is presented in Figure 5 with a cross section view presented on Figure 6. TABLE – TRENCH CHAMBER SCHEDULE Trench Number (West to East) Number of Chambers Trench Length (ft) Relative Infiltration Elevation (ft), Figure 6 Trench 1 13 52 7,820 Trench 2 13 52 7,821 Trench 3 13 52 7,823 Trench 4 13 52 7,824 OWTS COMPONENTS Recommended OWTS components provided below are based on our design details and our experience with the specific component manufacturers. Equivalent components may be feasible but need to be approved by us prior to construction. SEPTIC TANK 1. A 1,500-gallon, two-chamber, precast septic tank from Valley Precast, item #1500M-2CP or equivalent, is proposed for the OWTS. The first compartment must be at least 625 gallons. 2. The tank must be set level. The bottom of the excavation shall be free of large rocks or other objects that could damage the tank during placement. A gravel or road base bedding material may be necessary to prevent tank damage during placement and act as a leveling course. 117 Wolcott Springs Road Project Number: 22-1420 [5] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. 3. Install tank with 2 feet minimum cover soil for frost protection. Maximum soils cover depth is 4 feet or per manufacture’s recommendations. 4. The septic lids must extend to final surface grade and made to be easily located. 5. An effluent filter shall be located prior to the effluent piping to the STA. SEWER PIPE 1. The sewer line from the residence to the septic tank should not be less than the diameter of the building drain and not less than 4 inches in diameter. 2. A cleanout shall be located within 5 feet of the residence. If necessary, additional cleanouts are required every 100 feet of pipe and locations where the sewer pipe bends 90 degrees. 3. The sewer pipe should have a rating of SDR35 or better. The sewer pipe should be sloped between 2% and 4% to help limit disturbance of solids in the tank and potential sewage bypass of the first chamber of the tank. If a steeper slope is necessary, this can be accomplished with vertical step-downs in the sewer line, in the last 5 feet prior to the tank. 4. A minimum of 36 inches of cover soil should be provided over the sewer pipe. Paved areas, patios, or other areas without vegetative cover may be more susceptible to frost. We recommend a minimum of 48 inches of soil cover over the sewer pipe in these areas and the pipe be insulated on top and sides with 2- inch think blue foam insulation board. If adequate soil cover is not possible, we should be contacted for re-evaluation prior to construction. 5. The sewer pipe should be bedded in compacted ¾-inch road base or native soils provided that the native soils contain no angular rocks or rocks larger than 2.5-inches in diameter to help prevent settlement of the pipe. Sags could cause standing effluent to freeze and damage piping. 6. All 90-degree bends should be installed using a 90-degree long sweep or by using two 45-degree elbows. 7. The sewer line location shown on Figure 5 is considered conceptual. We assume that there will be only one sewer line exiting the residence. It is the responsibility of the owner to locate all sewer line exit locations and connections to the septic tank. We should be notified if there are other sewer lines exiting the residences. EFFLUENT TRANSPORT PIPING 1. We recommend 3-inch diameter SDR35 effluent transport piping. 2. The effluent transport pipe should be bedded in compacted ¾-inch road base or native soils, provided that the native soils contain no angular rocks or rocks larger than 2.5-inches in diameter to help prevent settlement of the pipe. Sags could cause standing effluent to freeze and damage piping. 3. A minimum of 18-inches of cover soil should be provided over the effluent transport pipe. Paved areas, patios, or other areas without vegetative cover may be more susceptible to frost. We recommend a minimum of 48 inches of soil cover over the sewer pipe in these areas and the pipe be insulated on top and sides with 2-inch thick blue foam insulation board. If adequate soil cover is not possible, we should be contacted for re-evaluation prior to construction. 4. The effluent pipe should be double encased with a larger diameter SDR35 pipe underneath driveway surfaces and be provided with a minimum of 48 inches of soil cover and be insulated on top and sides with 2-inch thick foam insulation board. 5. All 90-degree bends should be installed using a 90-degree long sweep or by using two 45-degree elbows. 6. The distribution box should be a Tuf-Tite 4-hole distribution box, or equivalent. Flow equalizers must be used to adjust the flow between the laterals. The levels and the distribution box should be installed per the manufacturer’s instruction. HOMEOWNER PRECAUTIONS The OWTS will require periodic inspection and maintenance to function properly. A properly designed, installed, and maintained system can greatly increase its lifespan. The level of maintenance will vary depending on the 117 Wolcott Springs Road Project Number: 22-1420 [6] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. complexity of the system and water use habits of the residents. Below are some basic recommendations for the OWTS operation and maintenance. HOUSEHOLD RECOMMENDATIONS 1. Use of a kitchen garbage disposal is not recommended. If garbage disposal is utilized, kitchen wastewater should be screened thoroughly. Many kitchen solids are not decomposed in the septic tank and may cause increase tank pumping frequency. 2. Water use should be monitored, and plumbing leaks fixed immediately as this may generate up to 1,000 gallons per day, which may flood the system and cause a hydraulic overload of the STA. 3. Use of high efficiency water fixtures is recommended to decrease the hydraulic load on the OWTS system. 4. Do not irrigate the area on top of or directly adjacent to the STA as this may cause a hydraulic overload of the STA. 5. Do not dispose of household waste down household drains as this may clog or damage the OWTS components. Examples of household waste include, but is not limited to: dental floss, cotton swabs, coffee grounds, paper towels, feminine products, and many other kitchen or bath items, etc. 6. Do not dispose of household chemicals, greases, oils, paints, hot tub water, or water softener brine in household drains. A separate drywell, if feasible, may be necessary for hot tub water or water softener brine disposal. 7. Limit the use of bleach as this may harm the useful bacteria in the septic tank and STA. 8. Liquid dishwasher and clothes detergent is recommended for households using OWTS. Clay substances used as fillers in powder detergents may result in clogging of the STA. MAINTENANCE 1. The effluent in septic tanks can freeze during extended period of non-use in cold weather. We recommend that a tank heater be installed in this system to help prevent freezing. 2. Inspect the septic tank, pump vault filter, treatment system, and soil treatment area at least annually for problems or signs of failure. 3. The pump vault filter should be cleaned annually by spray washing solids into the first chamber of the septic tank. 4. The septic tank should be pumped and cleaned every 3 to 5 years depending on use. Longer pumping intervals may increase the amount of solids that reach the soil treatment area, which may shorten the life span. 5. Pumping of the septic tank should take place when the level of the sludge and scum layers combined take up 25 to 33% of the capacity of the first chamber of the tank. LIMITATIONS This study has been conducted in accordance with generally accepted engineering practices in this area for exclusive use by the client for design purposes. Copying of this report or portions of this report without the express written permission of Best Engineering Solutions and Technologies, LLC (BEST), is specifically prohibited. We make no warranty either express or implied. The conclusions and recommendations submitted in this report are based upon data obtained from the exploratory test pits at the locations indicated on Figures 2 and 5, soil texture analysis, and the proposed construction. This report may not reflect subsurface variations that occur between the explorations. The nature and extent of variations across the site may not become evident until site grading and excavations are performed. If fill, soil, rock or water conditions appear to be different from those described herein, BEST should be advised at once so that a re-evaluation of the recommendations presented in this report can be made. BEST is not responsible for liability associated with interpretation of subsurface data by others. 117 Wolcott Springs Road Project Number: 22-1420 [7] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. It is our opinion that the designed location of the OWTS components does not violate any setback requirements of the current Eagle County Regulations. Below is a table of common minimum horizontal setbacks to OWTS components. Refer to the Eagle County Regulations for a complete list of required setbacks. We recommend that OWTS components be surveyed by a Professional Land surveyor licensed in Colorado and verified by BEST prior to the system permitting. TABLE 1 – COMMON MINIMUM HORIZONTAL SETBACKS FROM OWTS COMPONENTS Wells Water Supply Line Occupied Dwelling with Basement Property Lines, or Lined Ditch Lake, Irrigation Ditch, Stream, Wetland Dry Ditch, Gulch, or Cut Bank Septic Tank Absorption Trenches 100’ 25’ 20’ 10’ 50’ 25’ 5’ Septic Tank 50’ 10’ 5’ 10’ 50’ 10’ - Building Sewer Lines 50’ 5’ 0’ 10’ 50’ 10’ - Matthew A. Best, P.E. Project Engineer B.E.S.T. 189 13222-142013-8 BS0938 26 26 20 54 Loam23-8 BS0619625 29 46 Loam32.5-8 BS0829 12 29 24 47 Loam00 000 0TABLE: 1 Page 1 of 1AD=Air DriedC1= Unconfined CompressionCA=California SampleRM=Remolded SampleOR = Organic content of soilAS=Auger SampleSS=Split Spoon SampleGeoAdmin@BestEngineeringUSA.com Address: 1393 South Inca Street, Denver, Colorado 80223 ● Psalm 20 ● Phone: 303-238-1770ST=Shelby TubeHD=Hand DriveNOTE 3- Additional Test ResultsTT=Triaxial TestPT=ProctorWSS=Water Soluble SulfatesRA=Radon Testing (pCi/L)% Gravel +No. 4Additional Test Results (Note 3)CT=Consolidation TestATTERBERG LIMITS% Swell and Consolidation% Sand -No. 4 +No. 200% Fines -No. 200C2=Miniature CompressionC3=Pocket PenetrometerC4=Pocket ValuepH = pH of soilNOTE 2-Shear Strength Testshttps://bestengineeringusa.sharepoint.com/Shared Documents/Projects/22-1000 Summit Projects/22-1420 117 Wolcott Springs Road/Calcs/[22-1420 117 WolcottTABLE 1.1SUMMARY OF LABORATORY TEST RESULTSPROJECT:LOCATION: SOURCE:PROJECT NO:Field Test Boring / Lab TestingDATE:117 Wolcott Springs RoadWolcott, CONovember 15, 2024Boring No.BS=Bag SampleNat. Dry Density (PCF)Natural Moist. (%)GRADATIONSoil DescriptionLL PIDepth (ft)Sample Type (Note 1)NOTE 1- Sample Type B.E.S.T. 22-1420SITE MAP Project Number Figure 1GeoAdmin@BestEngineeringUSA.com Address: 1393 South Inca Street, Denver, Colorado 80223 ● Psalm 20 ● Phone: 303-238-1770NNot to Scale B.E.S.T. 22-1420 Project Number Figure 2GeoAdmin@BestEngineeringUSA.com BORING LOCATION LEGEND: B-1 – Indicates approximate location of exploratory boringAddress: 1393 South Inca Street, Denver, Colorado 80223 ● Psalm 20 ● Phone: 303-238-1770NNot to Scale 0' 2' 4' 6' 8' 10' 12' APPROXIMATE TEST PIT ELEVATIONS 0' 2' 4' 6' 8' 10' 12' TP-1 7,785' TP-2 7,791' TP-3 7,784' 22-1420 117 Wolcott Springs Road November 12, 2024 22-1420 117 Wolcott Wolcott, Colorado DRAWN BY: RJH REVIEWED BY: CV DATE: Address: 1393 South Inca Street Denver, CO 80223 TEST PIT LOGS Project Location:SCALE: Vertical: N/A Horizontal: N/A PROJECT NO:FIGURE: 3 X/12"Blow Counts; Number of Blows to Drive the Sampler 12-Inches (ASTM D-1586) (( X ))Depth of Caving Soils Undisturbed Sample Collected Disturbed Sample Collected ( 0 ) Water Level, Time After Drilling (0 = At Time of Drilling) NOTES: 1.The samples were collected on July 8, 2024 with a mini excavator. 2.The stratification lines represent the approximate boundary between soil types and the transition may be gradual. 3.The boring log(s) show subsurface conditions at the dates and locations indicated, and it is not warranted that they are representative of subsurface conditions at other locations or times. 4.Elevations are provided by Google Earth© and are considered approximate. Topsoil Loam, blocky, moderate Practical refusal of the mini excavator 22-1420 117 Wolcott Springs Road November 13, 2024 22-1420 117 Wolcott Springs Wolcott, Colorado DRAWN BY: RJH REVIEWED BY: CV DATE: Address: 1393 South Inca Street Denver, CO 80223 TEST PIT LOGS Project Location:SCALE: Vertical: N/A Horizontal: N/A PROJECT NO:FIGURE: 4 TP-1TP-3TP-2Distribution BoxSTASepticTankCleanoutNovember 13, 202422-1420 117 WolcottSprings Road.dwg22-1420 117 Wolcott Springs RoadWolcott, ColoradoDRAWN BY: DJOREVIEWED BY: MABDATE:Denver Office:1393 South Inca StreetDenver, CO 80223SEPTIC LAYOUT &TEST PIT LOCATIONProject Location:SCALE: As ShownFIGURE: 5PROJECT NO: SOIL TREATMENT AREA CROSS SECTION NW-SE12" Tall Infiltrator ChambersNative SoilMin. 12" Native SoilBackfill - Do Not CompactInfiltration Elevation1/4" Perforations spaced at 4'On-Center along bottomof pipeSOIL TREATMENT AREA CROSS SECTION SW-NE4" Dia. Inspection PortLateral Pipe, PerforatedSDR 35Scarify Soil 3" Below Level & RakeDo Not Compact or Smear Trench BottomTRENCH 1: 13 Infiltration ChambersMin. 4 Ft Spacingbetween Trenches Typ.Trench Width3 Ft Typ.SOIL TREATMENT AREA PLAN VIEWTRENCH 2: 13 Infiltration ChambersTRENCH 3: 13 Infiltration ChambersGround Surface VariesTrench - Infiltration ChamberElevation = 7,724'Max. 48"Native SoilLateral Pipe, PerforatedSDR 35Native SoilLateral Pipe,PerforatedSDR 35Min. 12" Native Type 2Soil Backfill - Do Not CompactMin. 12" Native Type 2Soil Backfill - Do Not CompactMax. 48"NativeSoilSouth Trench - InfiltrationChamber Elevation = 7,728'Native SoilSDR 35 PipeDistributionBoxNTRENCH 4: 13 Infiltration ChambersNovember 13, 202422-1420 117 WolcottSprings Road.dwg22-1420 117 Wolcott Springs RoadWolcott, ColoradoDRAWN BY: DJOREVIEWED BY: MABDATE:Denver Office:1393 South Inca StreetDenver, CO 80223SOIL TREATMENT AREA DETAILSProject Location:SCALE: As ShownFIGURE: 6PROJECT NO: 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com ONSITE WASTEWATER TREATMENT SYSTEM DESIGN 17 WOLCOTT SPRINGS ROAD WOLCOTT, COLORADO 81655 PROJECT NUMBER 22-1420 DECEMBER 6, 2023 PREPARED FOR RICHARD BENES 12 BLACKMER ROAD CHERRY HILLS VILLAGE, COLORADO 80113 Prepared By: Reviewed By: 12/6/2023 Nawal A. Obaid Matthew A. Best, P.E. Staff Engineer Project Engineer 1584 Hauck Meadow Drive Project Number: 23-1046 [2] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. Table of Contents PURPOSE AND SCOPE OF WORK ...................................................................................................................................................... 3 PROPOSED CONSTRUCTION.............................................................................................................................................................. 3 SITE CONDITIONS ................................................................................................................................................................................ 3 FIELD EXPLORATION ......................................................................................................................................................................... 3 SUBSURFACE CONDITIONS ............................................................................................................................................................... 3 OWTS ANALYSIS .................................................................................................................................................................................. 3 DESIGN RECOMMENDATIONS .......................................................................................................................................................... 4 HOMEOWNER PRECAUTIONS ........................................................................................................................................................... 5 LIMITATIONS ........................................................................................................................................................................................ 6 TABLE 1 – SUMMARY OF LABORATORY TEST RESULTS FIGURE 1 –SITE MAP FIGURE 2 – LOCATIONS OF EXPLORATORY TEST PIT FIGURE 3 – TEST PIT LOGS FIGURE 4 – LEGEND AND NOTES FIGURE 5 – SEPTIC LAYOUT FIGURE 6 – SOIL TREATMENT AREA DETAILS FIGURE 7 – SOIL TREATMENT AREA CALCULATIONS 1584 Hauck Meadow Drive Project Number: 23-1046 [3] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. PURPOSE AND SCOPE OF WORK This report presents the results of an onsite wastewater treatment system (OWTS) design for the project at 117 Wolcott Springs Road in Wolcott, Colorado. The purpose of this report is to provide design details for an OWTS in accordance with the 2018 Eagle County Onsite Wastewater Treatment System Regulations and the 2018 Colorado Department of Health and Environment Regulation Number 43. The project site is shown on Figure 1. Best Engineering Solutions and Technologies, LLC (BEST) conducted a subsurface exploration and provided foundation design recommendations in our Geotechnical Engineering Study report, dated November 11, 2022, and revised July 31, 2023. Please refer to this report for additional subsurface information. PROPOSED CONSTRUCTION We understand that the proposed residence will be a single-family home with an attached garage. The residence will have three bedrooms. The home will be conventional wood frame construction. If the number of bedrooms for the residence is different from what is described above, we should be notified to re-evaluate the recommendations contained in this report. SITE CONDITIONS At the time of our field exploration, the lot was vacant and was lightly covered with natural vegetation. The site is bounded by agricultural lands. The topography in the area slopes toward the north and east and is at an approximate ranging elevation of 7,815 to 7,821 feet MSL. FIELD EXPLORATION The field exploration was performed on October 21, 2022. The test pits were excavated approximately at the location shown on Figure 2 to evaluate the subsurface conditions. The test pits were excavated with a mini excavator and logged by a representative of BEST. Samples of the soils were taken with undisturbed sampling methods and the depths of the samples are shown on the Test Pit Logs, Figure 3 and Legend and Notes, Figure 4. SUBSURFACE CONDITIONS Test Pit TP-1 encountered silt loam to a depth of approximately 4 feet Below Existing Grade (BEG). Loam was encountered to the maximum depth explored of 7 feet BEG. Test Pit TP-2 encountered loam to a depth of approximately 5 feet BEG. Silt loam was encountered to the maximum depth explored of 8 feet BEG. Test Pit TP-3 encountered loam to the maximum depth explored of 6 feet BEG. Refusal was encountered in Test Pit TP- 3. Groundwater was not encountered during excavation of the test pits. Fluctuations in the groundwater levels may occur seasonally or with precipitation events. Samples taken from the exploratory test pits were retained for laboratory testing and inspected by the project engineer. The results of the tests performed on the samples obtained from the test pits are shown on Table 1. Laboratory testing included index property tests, such as moisture content and density, Atterberg limit test and gradation analysis. The testing was performed on bag samples obtained from the test pits. OWTS ANALYSIS We recommend a trench and infiltrator chamber system be used to provide effluent treatment from the proposed residence. The Soil Treatment Area (STA) was sized for a maximum of three bedrooms, Type 2 Loam with a Long-term acceptance rate (LTAR) of 0.60, and TL1. Calculations are provided in Figure 7. The effluent will gravity flow to the septic tank for primary treatment and will gravity flow to the STA for final treatment. 1584 Hauck Meadow Drive Project Number: 23-1046 [4] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. DESIGN RECOMMENDATIONS The design recommendations presented below are based on the proposed construction, the site, and subsurface conditions encountered and our experience in this area. If the conditions encountered during construction are different than those that are described in this report, please contact us and we will re-evaluate our design recommendations. SOIL TREATMENT AREA 1. The treatment system shall consist of four (4) trenches, each twelve (12) infiltration chambers long, see the table below. The trenches shall be a maximum width of 36-inches and shall be spaced at least 48 inches from trench wall to trench wall. The relative infiltration elevations shown on Figure 6 and provided in the table below are approximate and may need to be adjusted in the field to accommodate construction and actual elevation changes. 2. The chambers shall be Quick4 Plus Standard infiltrator chambers, or an approved equivalent. Chambers shall be installed in accordance with the manufacturer’s recommendations. 3. Topsoil within the proposed STA shall be stripped and removed prior to excavation of the trenches. 4. The maximum cut for the uphill side of the excavation to the infiltration surface shall be 4 feet from the ground surface. The bottom of the trench excavation should be scarified prior to chamber placement. 5. A minimum of 10 inches of cover soil should be placed over the chambers. The soil cover may consist of native soils. 6. Backfill should be graded to deflect surface water away from the STA and should be sloped at 3H:1V maximum. 7. Disturbed soil should be re-vegetated as soon as possible with a native grass seed mixture. No trees, shrubs, or other plants with deep roots should be planted on or near the STA as this may damage the system. 8. Four-inch diameter inspection ports should be installed vertically into the beginning and end of each trench. The inspection ports should extend at least 8 inches above the finished ground surface or be protected in a valve box at finished grade. The portion that lies within the gravel layer should be perforated. 9. A plan view of the STA is presented in Figure 5 with a cross section view presented on Figure 6. TABLE – TRENCH CHAMBER SCHEDULE Trench Number (West to East) Number of Chambers Trench Length (ft) Relative Infiltration Elevation (ft), Figure 6 Trench 1 12 48 7,818 Trench 2 12 48 7,818 Trench 3 12 48 7,818 Trench 4 12 48 7,818 OWTS COMPONENTS Recommended OWTS components provided below are based on our design details and our experience with the specific component manufacturers. Equivalent components may be feasible but need to be approved by us prior to construction. SEPTIC TANK 1. A 1,000 gallon, two-chamber, precast septic tank is proposed for the OWTS. The first compartment must be at least 500 gallons. 2. The tank must be set level. The bottom of the excavation shall be free of large rocks or other objects that could damage the tank during placement. A gravel or road base bedding material may be necessary to prevent tank damage during placement and act as a leveling course. 1584 Hauck Meadow Drive Project Number: 23-1046 [5] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. 3. Install tank with 2 feet minimum cover soil for frost protection. Maximum soils cover depth is 4 feet or per manufacture’s recommendations. 4. The septic lids must extend to final surface grade and made to be easily located. 5. An effluent filter shall be located prior to the effluent piping to the STA. SEWER PIPE 1. The sewer line from the residence to the septic tank should not be less than the diameter of the building drain and not less than 4 inches in diameter. 2. A cleanout shall be located within 5 feet of the residence. If necessary, additional cleanouts are required every 100 feet of pipe and locations where the sewer pipe bends 90 degrees. 3. The sewer pipe should have a rating of SDR35 or better. The sewer pipe should be sloped between 2% and 4% to help limit disturbance of solids in the tank and potential sewage bypass of the first chamber of the tank. If a steeper slope is necessary, this can be accomplished with vertical step-downs in the sewer line, in the last 5 feet prior to the tank. 4. A minimum of 36 inches of cover soil should be provided over the sewer pipe. Paved areas, patios, or other areas without vegetative cover may be more susceptible to frost. We recommend a minimum of 48 inches of soil cover over the sewer pipe in these areas and the pipe be insulated on top and sides with 2- inch think blue foam insulation board. If adequate soil cover is not possible, we should be contacted for re-evaluation prior to construction. 5. The sewer pipe should be bedded in compacted ¾-inch road base or native soils provided that the native soils contain no angular rocks or rocks larger that 2.5-inches in diameter to help prevent settlement of the pipe. Sags could cause standing effluent to freeze and damage piping. 6. All 90-degree bends should be installed using a 90-degree long sweep or by using two 45-degree elbows. 7. The sewer line location shown on Figure 5 is considered conceptual. We assume that there will be only one sewer line exiting the residence. It is the responsibility of the owner to locate all sewer line exit locations and connections to the septic tank. We should be notified if there are other sewer lines exiting the residences. EFFLUENT TRANSPORT PIPING 1. We recommend 2-inch diameter SDR35 effluent transport piping. 2. The effluent transport pipe should be bedded in compacted ¾-inch road base or native soils, provided that the native soils contain no angular rocks or rocks larger than 2.5-inches in diameter to help prevent settlement of the pipe. Sags could cause standing effluent to freeze and damage piping. 3. A minimum of 18-inches of cover soil should be provided over the effluent transport pipe. Paved areas, patios, or other areas without vegetative cover may be more susceptible to frost. We recommend a minimum of 48 inches of soil cover over the sewer pipe in these areas and the pipe be insulated on top and sides with 2-inch thick blue foam insulation board. If adequate soil cover is not possible, we should be contacted for re-evaluation prior to construction. 4. The effluent pipe should be double encased with a larger diameter SDR35 pipe underneath driveway surfaces and be provided with a minimum of 48 inches of soil cover and be insulated on top and sides with 2-inch thick foam insulation board. 5. All 90-degree bends should be installed using a 90-degree long sweep or by using two 45-degree elbows. HOMEOWNER PRECAUTIONS The OWTS will require periodic inspection and maintenance to function properly. A properly designed, installed, and maintained system can greatly increase its lifespan. The level of maintenance will vary depending on the complexity of the system and water use habits of the residents. Below are some basic recommendations for the OWTS operation and maintenance. 1584 Hauck Meadow Drive Project Number: 23-1046 [6] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. HOUSEHOLD RECOMMENDATIONS 1. Use of a kitchen garbage disposal is not recommended. If garbage disposal is utilized, kitchen wastewater should be screened thoroughly. Many kitchen solids are not decomposed in the septic tank and may cause increase tank pumping frequency. 2. Water use should be monitored, and plumbing leaks fixed immediately as this may generate up to 1,000 gallons per day, which may flood the system and cause a hydraulic overload of the STA. 3. Use of high efficiency water fixtures is recommended to decrease the hydraulic load on the OWTS system. 4. Do not irrigate the area on top of or directly adjacent to the STA as this may cause a hydraulic overload of the STA. 5. Do not dispose of household waste down household drains as this may clog or damage the OWTS components. Examples of household waste include, but is not limited to: dental floss, cotton swabs, coffee grounds, paper towels, feminine products, and many other kitchen or bath items, etc. 6. Do not dispose of household chemicals, greases, oils, paints, hot tub water, or water softener brine in household drains. A separate drywell, if feasible, may be necessary for hot tub water or water softener brine disposal. 7. Limit the use of bleach as this may harm the useful bacteria in the septic tank and STA. 8. Liquid dishwasher and clothes detergent is recommended for households using OWTS. Clay substances used as fillers in powder detergents may result in clogging of the STA. MAINTENANCE 1. The effluent in septic tanks can freeze during extended period of non-use in cold weather. We recommend that a tank heater be installed in this system to help prevent freezing. 2. Inspect the septic tank, pump vault filter, treatment system, and soil treatment area at least annually for problems or signs of failure. 3. The pump vault filter should be cleaned annually by spray washing solids into the first chamber of the septic tank. 4. The septic tank should be pumped and cleaned every 3 to 5 years depending on use. Longer pumping intervals may increase the amount of solids that reach the soil treatment area, which may shorten the life span. 5. Pumping of the septic tank should take place when the level of the sludge and scum layers combined take up 25 to 33% of the capacity of the first chamber of the tank. LIMITATIONS This study has been conducted in accordance with generally accepted engineering practices in this area for exclusive use by the client for design purposes. Copying of this report or portions of this report without the express written permission of Best Engineering Solutions and Technologies, LLC (BEST), is specifically prohibited. We make no warranty either express or implied. The conclusions and recommendations submitted in this report are based upon data obtained from the exploratory test pits at the locations indicated on Figures 2 and 5, soil texture analysis, and the proposed construction. This report may not reflect subsurface variations that occur between the explorations. The nature and extent of variations across the site may not become evident until site grading and excavations are performed. If fill, soil, rock or water conditions appear to be different from those described herein, BEST should be advised at once so that a re-evaluation of the recommendations presented in this report can be made. BEST is not responsible for liability associated with interpretation of subsurface data by others. It is our opinion that the designed location of the OWTS components does not violate any setback requirements of the current Eagle County Regulations. Below is a table of common minimum horizontal setbacks to OWTS components. Refer to the Eagle County Regulations for a complete list of required setbacks. We recommend that 1584 Hauck Meadow Drive Project Number: 23-1046 [7] 1393 South Inca Street, Denver, Colorado 80223  Psalm 20  Phone: 303-238-1770 Office@bestengineeringusa.com B.E.S.T. OWTS components be surveyed by a Professional Land surveyor licensed in Colorado and verified by BEST prior to the system permitting. TABLE 1 – COMMON MINIMUM HORIZONTAL SETBACKS FROM OWTS COMPONENTS Wells Water Supply Line Occupied Dwelling with Basement Property Lines, or Lined Ditch Lake, Irrigation Ditch, Stream, Wetland Dry Ditch, Gulch, or Cut Bank Septic Tank Absorption Trenches 100’ 25’ 20’ 10’ 50’ 25’ 5’ Septic Tank 50’ 10’ 5’ 10’ 50’ 10’ - Building Sewer Lines 50’ 5’ 0’ 10’ 50’ 10’ - Matthew A. Best, P.E. Project Engineer B.E.S.T. 192 13922-1420TP-1 1.5-4 AS06 33 16 7 17 76 Silt loamTP-1 6 HD 4 41 55 SW= 4.5 WSS= 20.0 LoamTP-2 2-5 AS06 341610 21 69 LoamTP-2 5-8 AS07 28 16 5 19 76 Silt loamTP-3 1.5-6 AS0538205 31 64 LoamTABLE: 1 Page 1 of 1Boring No.BS=Bag SampleNat. Dry Density (PCF)Natural Moist. (%)GRADATIONLL PIDepth Sample Type (Note 1)NOTE 1- Sample Type% Gravel +No. 4https://bestengineeringusa.sharepoint.com/Shared Documents/Projects/22-1000 Summit Projects/22-1420 117 Wolcott Springs Road/Calcs/Septic/[22-1420 117 TABLE 1.1SUMMARY OF LABORATORY TEST RESULTSPROJECT:LOCATION: SOURCE:PROJECT NO:Field Test Boring / Lab TestingDATE:117 Wolcott Springs RoadWolcott, CODecember 6, 2023Additional Test Results (Note 3)CT=Consolidation TestATTERBERG LIMITS% Swell and Consolidation% Sand -No. 4 +No. 200% Fines -No. 200C2=Miniature CompressionC3=Pocket PenetrometerNOTE 2-Shear Strength TestsSoil DescriptionNOTE 3- Additional Test ResultsTT=Triaxial TestPT=ProctorC1= Unconfined CompressionWSS=Water Soluble SulfatesRA=Radon Testing (pCi/L)pH = pH of soilAD=Air DriedCA=California SampleRM=Remolded SampleOR = Organic content of soilAS=Auger SampleST=Shelby TubeHD=Hand DriveC4=Pocket ValueSS=Split Spoon SampleGeoadmin@BestEngineeringUSA.com Address: 1393 South Inca Street, Denver, Colorado 80223 ● Psalm 20 ● Phone: 303-238-1770 B.E.S.T. 22-1420SITE MAP Project Number Figure 1Geoadmin@BestEngineeringUSA.com Address: 1393 South Inca Street, Denver, Colorado 80223 ● Psalm 20 ● Phone: 303-238-1770NNot to Scale B.E.S.T. 22-1420 Project Number Figure 2Geoadmin@BestEngineeringUSA.com BORING LOCATION LEGEND: B-1 – Indicates approximate location of exploratory boringAddress: 1393 South Inca Street, Denver, Colorado 80223 ● Psalm 20 ● Phone: 303-238-1770NNot to Scale 25'NDistribution BoxSTACleanoutSepticTank7,7367,7347,7327,7307,7287,7267,7247,7227,72050'-9"December 6, 202322-1420 117 WolcottSprings Road.dwg22-1420 117 Wolcott Springs RoadWolcott, ColoradoDRAWN BY: NAOREVIEWED BY: MABDATE:Denver Office:1393 South Inca StreetDenver, CO 80223SEPTIC LAYOUTProject Location:SCALE: 1=0.75FIGURE: 5PROJECT NO: SOIL TREATMENT AREA CROSS SECTION NW-SE12" Tall Infiltrator ChambersLoamMin. 12" Native SoilBackfill - Do Not CompactInfiltration Elevation1/4" Perforations spaced at 4'On-Center along bottomof pipeSOIL TREATMENT AREA CROSS SECTION SW-NE4" Dia. Inspection PortLateral Pipe, PerforatedSchedule 40Scarify Soil 3" Below Level & RakeDo Not Compact or Smear Trench BottomTRENCH 1: 12 Infiltration ChambersMin. 4 Ft Spacingbetween Trenches Typ.Trench Width3 Ft Typ.SOIL TREATMENT AREA PLAN VIEWTRENCH 2: 12 Infiltration ChambersTRENCH 3: 12 Infiltration ChambersGround Surface VariesNorth Trench - InfiltrationChamber Elevation = 7,724'Max. 48"Native SoilLateral Pipe, PerforatedSchedule 40Native Type 2 LoamLateral Pipe,PerforatedSchedule 40Min. 12" Native Type 2Soil Backfill - Do Not CompactMin. 12" Native Type 2Soil Backfill - Do Not CompactMax. 48"NativeSoilSouth Trench - InfiltrationChamber Elevation = 7,728'Native Type 2 LoamSDR 35 PipeDistributionBoxNTRENCH 4: 12 Infiltration ChambersDecember 6, 202322-1420 117 WolcottSprings Road.dwg22-1420 117 Wolcott Springs RoadWolcott, ColoradoDRAWN BY: NAOREVIEWED BY: MABDATE:Denver Office:1393 South Inca StreetDenver, CO 80223SOIL TREATMENT AREA DETAILSProject Location:SCALE: As ShownFIGURE: 6PROJECT NO: OWTS SOILS TREATMENT AREA CALCULATIONS In accordance with the current Eagle County Onsite Wastewater Treatment Systems Regulations, dated August 24, 2018, the absorption area was calculated as follows: CALCULATION OF OWTS DESIGN FLOW Q = (F)(B)(N), where: Q = Design Flow F = Average flow per person per day B = Number of bedrooms N = Number of persons per bedroom F = 75 Gallons per day B = 3 Bedrooms N = 2 Persons per bedroom Q = 450 Gallons per day SEPTIC TANK CAPACITY Septic tank should be listed as “Accepted for use in Colorado on-site wastewater treatment systems.” Minimum tank capacity = 1,000 gallons; Minimum first compartment capacity = 500 gallons (Per Table 9-1) CALCULATION OF OWTS TREATMENT AREA Minimum soil treatment area (STA) = Q / Loam LTAR, Where: Q = 450 Gallons per day Type 2 Loam LTAR (Eagle County Table 10-1) = 0.60 Gallons/square foot/day Minimum STA = 750 square feet Adjustment factor for trenches, 1.0; for infiltrator chambers, 0.7 (Eagle County Table 10-2 and 10-3) Required STA = Min. STA x trench adjustment x infiltrator adjustment Required STA = 525 Square Feet OWTS DESIGN TREATMENT AREA Standard Chamber Trench Width 3 feet; Standard Chamber Length = 4 feet Area per Chamber = 12 SF Minimum Trench Separation = 4 feet Minimum Number of Chambers = 525/ 12 = 44 Four Trenches with 12 chambers and 48 feet long Designed Number of Chambers = 48, See Figure 6. December 6, 2023 22-1420 117 Wolcott Springs Road.dwg 22-1420 117 Wolcott Springs Road Wolcott, Colorado DRAWN BY: NAO REVIEWED BY: MAB DATE: Denver Office: 1393 South Inca Street Denver, CO 80223 SOIL TREATMENT AREA CALCULATIONS Project Location:SCALE: Vertical: NTS Horizontal:NTS FIGURE: 7PROJECT NO: