HomeMy WebLinkAboutEngineer's OWTS DesignIED Huddleston-Berry Engineering &Testing, LLC Joe Reider 1620 County Road 21 Brighton, Colorado 80603 Subject: OWTS Design Parcel 24072300004 Parachute, Colorado 2789 Riverside Parkway Grand Junction, Colorado 81501 Phone: 970-255-8005 Info huddlestonberry.com August 27, 2024 Project#02850-0001 Reference: Geotechnical Investigation, Parcel 24072300004, Parachute, Colorado by Huddleston-Berry Engineering & Testing, LLC for Joe Reider, June 7, 2024. Dear Mr_ Reider, At your request, Huddleston-Berry Engineering & Testing, LLC completed design of an Onsite Wastewater Treatment System (OWTS) for a single-family residence at Parcel 24072300004 in Parachute, Colorado. The site location is shown on Figure 1 — Site Location Map. A site plan is included as Figure 2. Site Description At the time of the investigation, the investigated area was open. The northwest portion of the site was fairly flat, and vegetation primarily consisted of grasses and weeds. The center and southeast portions of the site contained moderate to steep slopes down to the adjacent canyon, and vegetation consisted of grasses, weeds, and trees. Site topography is shown on Figure 2. Vegetation consisted primarily of weeds and grasses. The site was bordered to the north by a vacant lot and a rural residential property, to the west and south by rural residential properties, and to the east by Federal Land. Subsurface Investigation As discussed in the referenced report, the subsurface conditions at the site were fairly consistent. Using visual -tactile classification methods, the soil profile consisted of 1.0 foot of topsoil above reddish -tan to brown, moist, medium dense silt loam to silt loam with gravel soils with a moderate granular structure that extended to the bottoms of the borings and excavations. The site soils are consistent with Soil Type 2 with less than 35% rock. Groundwater was not encountered in the subsurface at the time of the investigation. In general, based upon the results of the subsurface investigation, MET believes that the seasonal high groundwater elevation is deeper than 8.0 feet below the existing grade at this site. The locations of the borings and test pits are shown on Figure 2. Copies of the boring and test pit logs are included in Appendix A. Parcel 240702300004 #02850-0001 08/27/24 Onsite Wastewater Treatment System +,LL�rn�rni--i77 HudiUcAon-Berry ice/v E-,m-M,g& T-T g. LLC Seepage Bed Design The design of the absorption system generally follows the requirements of the Garfield County Department of Public Works as outlined in the Garfield County On -Site Wastewater Treatment System Regulations, effective June 2018. The proposed construction at the site is anticipated to include a single bedroom home. However, Garfield County regulations that a minimum of two bedrooms be considered per habitable structure. Therefore, the design will consider a two - bedroom home. Based upon the visual tactile classification of the soils, a Long --Term Acceptance Rate (LTAR) of 0.6 will be utilized for the absorption field design. Infiltrator Systems Quick4 Standard Chambers are proposed. The daily flow of the sewage disposal system is calculated below and a plan and profile of the absorption system are shown on Figure 3. Average Daily Flow = (4 persons)(75 GPD/person) = 300 GPD Soil Treatment Area = (300 GPD / 0.6) = 500 Square Feet Adjusted Soil Treatment Area = (500 SF)(1.2)(0.7) = 420 Square Feet # of Quick4 Chambers = (420 / 12) = 35 Chambers; Use 36 Chambers System Installation The installation of the septic tank, plumbing lines, Infiltrators, etc. should be completed in accordance with the Garfield County On -Site Wastewater Treatment System Regulations and Infiltrator Systems, Inc. specifications. In addition, the following construction procedures are recommended: The septic tank and distribution box should be placed level over native soils that have been scarified to a depth of 8 to 12 inches, moisture conditioned, and recompacted to a minimum of 95% of the standard Proctor maximum dry density, within ±2% of optimum moisture content. However, up to 3-inches of washed rock or pipe bedding passing the 1-inch sieve may be used as a leveling course under the septic tank and/or distribution box. The bottoms of trenches and backfill around the septic tank and distribution box which will support sewer or effluent lines should be compacted to at least 90 percent of the standard Proctor maximum dry density, within f2% of optimum moisture content. Pipe bedding should have a maximum particle size of 1-inch. Vehicular or heavy equipment traffic and placement of structures should not encroach within 10 feet of the septic tank or distribution box. Inspection Schedule Huddleston-Berry Engineering & Testing LLC should be retained to monitor the construction of the OWTS. The following schedule of observation and/or testing should be followed: ■ Observe the absorption bed excavation prior to placement of Infiltrator chambers. ■ Observe placement of the septic tank, distribution box, and all connecting sewer and effluent lines prior to backfill. Verify proper fall between inverts. V:12008 ALL PR0JECTS102850 - Joe Reidzrr%2850-000I Panel 2407023000041200 - Ce W2850-Ooai OWFS082724.doc 2 Parcel 240702300004 #02850-0001 08/27/24 8 Huddleston-Berry T-Ii�,. UC Observe and verify installation of the absorption bed prior to placement of cover and backfill. In conformance with Garfield County regulations, HBET will be required to provide the Garfield County Health Department with documentation certifying that the OWTS was placed in conformance to the plan and profile and Garfield County regulations. General Notes The OWTS design was based upon the results of the subsurface investigation and on our local experience. The design is valid only for the proposed construction. We are pleased to be of service to your project. Please contact us if you have any questions or comments regarding the contents of this report. Respectfully Submitted: Huddleston-Berry Engineering and Testing, LLC ,�RpQ LIB 3679 ,.g 27/24RI V Oy b �• /ONALL Wayne D. Anderson, P.E. Project Engineer V:52006 ALL PROfECTS102050 - foe Reider102050-000I Parcel 240702300004\200 - Geo\0285MOOI OWTS062724.doc 3 �gPublic.net`" Garfield County, CO Date created: 5/16/2024 Last Data Uploaded: 5/16120242:17:10AM Developed by" Schneider GE SPATIAL FIGURE 1 Site Location Map 0 a r N N H O J y o Cr1 w a o z A j 0~ o= ~ � ci'• m IS � � v► � _ m 'r z m 0 A 1 n Sol noi� 0 1 - \ L---------- /—__J b / \ q a o � � 0 � < � o r� o >• d 003 �0 un 08 a ad IA In{s1 a ; R � q La W Z O w r l m aHo U U b qq a 2 bI I I vM en z o '+� rn -n 3 u = N tn F�•S O O � O �] n � : n� •y': � as W U Ll I g F w E vi r pp 5s` {Q{tt J o ° F QI I F I 2 wed I za�4° W � I mF I rlaR g- �_�{ W N j x o yZ� time `�� I w� I o0^ s s 3 o I U F» Q w w � p z HN I c s F.y E 14d2 I r U a mgg�OCJ I ciaz I r Cd Yq'3 ((99 s q a Edy N1�.7 F �(� w ZJ F' ,� G APPENDIX A Typed Boring & Test Pit Logs �6VtEr Huddleston-Berry Engineering & Testing LLC BORING NUMBER B-2 . 2799 Riverside Parkway PAGE 1 OF 1 Grand Junction, CO 81501 s 970-255-8005 CLIENT Joe Reider PROJECT NAME Parcel 240702300004 PROJECT NUMBER 02B50-0001 PROJECT LOCATION Parachute, CO DATE STARTED 5/20/24 COMPLETED 5/20/24 GROUND ELEVATION HOLE SIZE 4-Inch MILLING CONTRACTOR S. McKracken GROUNDWATER LEVELS: DRILLING METHOD Simco 2000 Truck Rig_ _ AT TIME OF DRILLING Dry LOGGED BY TC CHECKED BY MAB AT ENDOF DRILLING Dry NOTES AFTER DRILLING -- ATTERBE=RG i— a Cr z w w o LIMITS w O �— w p MATERIAL DESCRIPTION J j of 2) 7 Lu� z �v � o 5— F- M v o p 2Z 0 MO z OZ �� �� J �� z U) w t¢ w O o x p 20 U —r a z 0 a- LL —' Silty Sand with Organics (TOPSOIL) r�:�ir;• ----------------------------- Silt Loam, reddish -tan to brown, moist, medium dense, moderate granular structure (Soil Type 2) SS 67 3-1-2 1 (3) 5 SS 2 39 8-30 10 Silt Loam with Gravel, reddish -tan to brown, moist, medium dense, moderate granular structure (Soil Type 2 with <35% Rock) IS 50 30-20 3 15 SS 4 46 25-50 20 i Bottom of hole at 20.0 feet. m z 2 Zi 0 U m V W H O w C7 wa�`nEFR,ti� Huddleston-Berry En&eering & Testing, LLC TEST PIT NUMBER TP-1 Riverside Parkway PAGE 1 OF 1 12789 = Grand Junclion, CO 81501 970-255-8005 CLIENT Joe Reider PROJECT NAME Parcel 240702300004 PROJECT NUMBER 02850-0001 PROJECT LOCATION Parachute, CO DATE STARTED 5120124 COMPLETED 5120/24 GROUND ELEVATION TEST PIT SIZE EXCAVATION CONTRACTOR Wiseland GROUND WATER LEVELS: EXCAVATION METHOD TrackhlBackhoe AT TIME OF EXCAVATION Dry _ LOGGED BY TC CHECKED BY MAB AT END OF EXCAVATION Dry NOTES AFTER EXCAVATION - ATTERBERG F— w a o w uj LIMITS w O F } }�v- a w d O MATERIAL DESCRIPTION WM uj ujc 0 0Z i2zn� �� w ��� — } O va U C7 0 m0§� UZ :E �J Co ❑ c¢n O x 20 =iD a w 0.0 ei Silty Sand with Organics (TOPSOIL) .�51j •�1 Silt Loam, reddish -tan, moist, medium dense, moderate granular structure (Soil Type 2) 2,5 ------------- Bottom of test pit at 6.0 feet. 5.0 a W C a z 0 U U 2 00 2 U W 0 W W %NEFR�yp Huddleston-Berry Engineering & Testing, LLC TEST PIT NUMBER TP-2 2789 Riverside Parkway PAGE 1 OF 1 I& (nand Junction, CO 81501 970-255-8005 CLIENT Joe Reider PROJECT NAME Parcel 240702300004 PROJECT NUMBER 02850-0001 PROJECT LOCATION Parachute, CO DATE STARTED 5/20124 COMPLETED 5120124 GROUND ELEVATION TEST PIT SIZE EXCAVATION CONTRACTOR Wiseland GROUND WATER LEVELS: EXCAVATION METHOD Trackh/Backhoe AT TIME OF EXCAVATION Dry LOGGED BY TC CHECKED BY MAB AT END OF EXCAVATION Dry NOTES AFTER EXCAVATION -- ATTERBERG a o z w W o LIMITS w WO 'EQ j O¢ w _ H O MATERIAL DESCRIPTION F U o ❑ C7 QZ 0" m0z Uv r Oz O� U)❑ z cn c4 0' d Q �0 J a_z uJ 0.0 �- '— Silty Sand with Organics (TOPSOIL) ;1,;. Silt Loam, reddish -tan, moist, medium dense, moderate granular structure (Soil Type 2) 2.5 5.0 Bottom of test pit at 6.0 feet. Zpppp Ndddt101 � (25 � ma le JVAUAM 9w"Pi .lfi AAA $y ov,•:5, 'T�p1N MEL/ns n A, IS 014 .4Anx AA .YES-UR7Ar A Y.YR' .. .•"^`"••^•;7":»"xta"".„::.„.�:5t�'"' '.ic.« .d: ,Y• r;w]•� 1"'dC•.r,^ dVtYtb 4w Fdk45?N AM! Mgx7tki.V71