HomeMy WebLinkAboutUpdated OWTS Design Plan - 09.26.2024SS
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Unit #7
(3 Bed)
Unit #3
(1 Bed)
Unit #8
(1 Bed)
Unit #4a
(1 Bed)
Unit #4b
(1 Bed)
Unit #2
(1 Bed)
Unit #1
(1 Bed)
Unit #9
2 Bed)
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Unit #6
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Shed
Storage Units
Storage Units
Existing
Septic Field
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R116' MIN. WELL SETBACK
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Union Pacific Railroad
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Main Street / Highway 6
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OE OE OE OE OE OE OE OE OE OE OE OE OE
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OE OE
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10' MIN.
6' MIN., TYP.
CONSTRUCT 2 ADD'T BEDS
(4x13 QUICK 4 UNITS EACH)
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FLUSH VALVE
ASSEMBLY, TYP.
(4 PER BED)
EXISTING 2,000-GALLON
SINGLE-COMPARTMENT
PRECAST CONCRETE
SEPTIC TANK
INSTALL TWO (2) ADD'T 1-1/2"Ø SCH.40
PVC DISTRIBUTION LATERALS, TYP.
EX. 1-1/2"Ø SCH.80 PVC
TRANSPORT PIPE
REPLACE THE EX. 4-ZONE
DISTRIBUTION VALVE WITH A
6-ZONE DISTRIBUTION VALVE
EXISTING 1,000-GALLON
TWO-COMPARTMENT PRECAST
CONCRETE SEPTIC TANK W/
HIGH HEAD DOSING PUMP
EXISTING SEPTIC TANKS
(2000± GALLONS
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10
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1-1/2"x1-1/4" SCH.40 PVC REDUCER, TYP.
INSPECTION PORT,
TYP. (4 PER BED)
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TP#2
PROFILE
PIT
TP#1
TP#3
TP#4
TO SUPPORT:
UNITS #6, 9 & 11
RV(s) #5, 10, 12, 15, & 16)
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EX. BED
(52 QUICK 4 UNITS)
EX. BED
(52 QUICK 4 UNITS)
EX. BED
(52 QUICK 4 UNITS)
EX. BED
(52 QUICK 4 UNITS)
Scale: N.T.S.
Site & Soils Evaluation
Scale: N.T.S.
Purpose and Existing System
Scale: N.T.S.
Flush Valve
Scale: N.T.S.
Automatic Distributing Valve
00 20'40'
Scale: 1" = 20'
37110DERIC J O N WA
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COL O R A D O LICE
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SSIONA L E N G INEER
9/25/24
NORTH
RevisionDate
923 Cooper Avenue, Ste. 201
Glenwood Springs, CO 81601
tele: 970.945.5252
www.bu-inc.com
Engineer or Surveyor Seal
Sheet
Client Information:
Project No.:
Filename:
Designer:
Drafter:
Date:
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Subsurface Utility Engineering (SUE)
Required Project:
If "Yes", SUE Certification by:
Firm:
Job #:
Date:
Agency Approval
Agency:
Dept:
By:
Date:
Comments:
9/25/24
DJW
DJW
17026-owts-2024.dwg
17026
970.200.6020
Grand Junction, CO 81505
737 Corral Drive
3M Investors, LLC
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9/25/24 Rev. inspection ports & note #2.A
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C.1
No
N/A
N/A
N/A
ORIGINAL SOIL EVALUATION (2017)
1.SOIL PERCOLATION TESTS IN THE NATIVE SOILS (SILTY CLAY LOAM) RANGED FROM 43-75
MPI (60 MPI AVERAGE) INDICATING A SOIL TYPE OF 3 AND AN LTAR OF 0.35 GPD/SF.
2.NO GROUNDWATER WAS ENCOUNTERED OR OBSERVED IN THE 8-FOOT DEEP PROFILE PIT.
SITE EVALUATION
1.SITE AND SOIL EVALUATIONS WERE PERFORMED BY:
DERIC J. WALTER, PE
BOUNDARIES UNLIMITED INC.
923 COOPER AVE., STE. 201
GLENWOOD SPRINGS, CO 81601
970.945.5252
2.EVALUATION DATE(S): SEPTEMBER 24, 2017.
3.SETBACK REQUIREMENTS FOR A TREATMENT LEVEL 1 (TL1) STA TRENCH/BED, UNLINED
SAND FILTER OR SEEPAGE PIT (PER TABLE 7-1) AND AN ADWF=1,199 GPD:
3.A.SPRING OR WELL=100' + 16' = 116'
3.B.POTABLE WATER SUPPLY LINE=25'
3.C.POTABLE WATER SUPPLY CISTERN=25'
3.D.DWELLING=20'
3.E.PROPERTY LINE, PIPE OR LINED IRRIGATION DITCH=10'
3.F.INTERMITTENT IRRIGATION LATERAL, INFILTRATION STRUCTURE=25'
3.G.LAKE, WATER COURSE, IRRIGATION DITCH, STREAM OR WETLAND=50' + 16' = 66'
3.H.DRY GULCH, CUT BANK OR FILL AREA=25'
3.I.SEPTIC TANK=5'
3.J.RESTRICTIVE LAYER OR GROUNDWATER (VERTICAL): 4' (TL 1, GRAVITY FEED)
3.SETBACK REQUIREMENTS FOR THE SEPTIC TANK SHALL BE (PER TABLE 7-1):
3.A.SPRING OR WELL=50'
3.B.POTABLE WATER SUPPLY LINE=10'
3.C.POTABLE WATER SUPPLY CISTERN=25'
3.D.DWELLING=5'
3.E.PROPERTY LINE, PIPE OR LINED IRRIGATION DITCH=10'
3.F.INTERMITTENT IRRIGATION LATERAL, INFILTRATION STRUCTURE=10'
3.G.LAKE WATER COURSE, IRRIGATION DITCH, STREAM OR WETLAND=50'
3.H.DRY GULCH, CUT BANK OR FILL AREA=10'
3.I.STA TRENCH/BED, UNLINED SAND FILTER OR SEEPAGE PIT=5'
SURFACE
12"
SILTY
CLAY
LOAM
(TYPE-3)
Vicinity Map
1"=2000'
TOPSOIL
7'
±
NO
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T
H
SITE
To New Castle
Hwy. 6
Silt
PREFABRICATED PIPE SUPPORT OR
CHEMICAL RESISTANT ZIP TIE
HANGING SYSTEM (PIPE @ 6" MIN.
ABOVE BASE )
MAINTENANCE NOTES
1.TO ENCOURAGE THE HEALTH AND LONGEVITY OF THE OWTS SYSTEM,
THE OWNER SHALL CONSIDER THE FOLLOWING:
1.A.MINIMIZE THE AMOUNT OF WATER THAT GOES DOWN THE DRAIN,
THE BETTER YOUR SYSTEM WILL WORK.
1.B.MINIMIZE SOLIDS GOING DOWN THE DRAIN.
1.C.ELIMINATE GARBAGE DISPOSALS OR KEEP THE USE OF GARBAGE
DISPOSALS TO A MINIMUM.
1.D.MINIMIZE GREASE AND OILS THAT GO DOWN THE DRAIN.
1.E.USE LINT FILTERS ON LAUNDRY MACHINE DRAINS.
1.F.KEEP SAND AND DIRT OUT OF THE BUILDING DRAIN.
1.G.AVOID FLUSHING SANITARY NAPKINS OR PAPER PRODUCTS
OTHER THAN TOILET PAPER.
1.H.DO NOT USE LYE-BASED DRAIN UNCLOGGER CHEMICALS SUCH
AS DRAINO, OVEN-OFF, OR OTHER STRONG CLEANING AGENTS.
1.I.DO NOT PUT ANY “ROOT DETERRENTS” DOWN THE DRAIN.
1.J.DO NOT POUR PAINT THINNER, PESTICIDES, PAINTS OR PHOTO
LAB CHEMICALS DOWN THE DRAIN
1.K.MINIMIZE USE OF CHLORINE BLEACH AND TOILET ADDITIVES.
2.THE OWNER SHALL CONTRACT WITH A SEPTIC TANK INSPECTOR TO
INSPECT THE TANK ANNUALLY FOR GREASE AND SEDIMENT
ACCUMULATION. THE INSPECTOR SHALL REMOVED AND PROPERLY
DISPOSED OF ACCUMULATED GREASE AND SEDIMENT AS NEEDED TO
ENSURE PROPER FUNCTION OF THE SYSTEM.
1-1/4"Ø PVC
DISTRIBUTION PIPE
1-1/4"Ø PVC ELBOW
1"Ø BALL VALVE &
TREADED
ASSEMBLY10"Ø IRRIG. VALVE
BOX
1-1/4" x 1" PVC
REDUCER
1-1/2"Ø SCH.80
PVC FROM PUMP
EX. STYROFOAM INSULATED
FIBERGLASS LID WITH STAINLESS
STEEL BOLTS AND URETHANE GASKET
24"Ø PVC
ENCLOSURE
GRAVEL BASE
REPLACE THE EX. VALVE WITH AN
ORENCO 6 ZONE 1-1/2"Ø DISTRIBUTING
VALVE ASSEMBLY (V6606A)
CHECK VALVES
ORIGINAL SYSTEM DESIGN NOTES:
1.ALL CONSTRUCTION SHALL BE IN ACCORDANCE WITH GARFIELD COUNTY ONSITE WASTEWATER TREATMENT SYSTEMS (OWTS) REGULATIONS, MOST
CURRENT EDITION AND LOCAL AGENCY REQUIREMENTS WHICH MAY OR MAY NOT SPECIFICALLY BE NOTED ON THE DRAWINGS. THE CONTRACTOR
SHALL BE RESPONSIBLE FOR KNOWING AND CONFORMING TO SUCH SPECIFIC DETAILS AS ARE REFERRED TO IN THE ABOVE MENTIONED REGULATIONS.
THIS DRAWING DOES NOT CONSTITUTE AN OWTS PERMIT. A PERMIT MUST BE OBTAINED FROM APPROPRIATE LOCAL AGENCY. THE ENGINEER MUST
OBSERVE THE CONSTRUCTED SYSTEM BEFORE BACKFILL AND PROVIDE A LETTER OF INSPECTION AS REQUIRED BY THE LOCAL AGENCY. A REQUEST
FOR INSPECTION MUST BE MADE BY THE CONTRACTOR AT LEAST 48-HOURS PRIOR TO THE EXPECTED TIME OF BACKFILLING.
2.DEMAND CALCULATIONS (SEC.43.6.A.2.h)
2.A.ONE (1) THREE (3) BEDROOM RESIDENCE PLUS SIX (6) ONE (1) BEDROOM RESIDENCES PLUS TWO (2) RECREATIONAL VEHICLE (RV) SPACES
USING DOSING AND TREATMENT LEVEL 1 (TL1).
2.B.AVERAGE DAILY WASTEWATER FLOW (ADWF):
2.B.1.SINGLE FAMILY DWELLING WITHOUT A LAUNDRY WASHER (NO LAUNDRY FACILITIES ONSITE): 75 gpdc - 19.5 gpdc = 55.5 gpdc.
2.B.2.TRAVEL TRAILER PARKS (RV) WITH INDIVIDUAL WATER AND SEWER HOOKUP PER UNIT (NO LAUNDRY FACILITIES ONSITE): 100 gpd
2.B.3.ADWF = (55.5 gpdc * (3 BEDROOMS * 1 UNIT+1 BEDROOM * 6 UNITS) * 2 PERSONS/BEDROOM )) + (100 gpd * 2 RVs ) = 1,199 gpd
3.SEPTIC TANK (SEC.43.9.B.2.a):
3.A.DOSING IS TO BE USED. THEREFORE, 48 HOURS OF DETENTION IS REQUIRED: ADWF*(48/hrs/24hrs) = 1,199 gpd * (48/HRS/24HRS) = 2,398
GALLONS
3.B.INSTALL A 2,000-GALLON SINGLE-COMPARTMENT TANK IN SERIES WITH A 1,000-GALLON TWO (2) COMPARTMENT TANK WITH A HIGH HEAD
DOSING PUMP SYSTEM IN THE 2nd COMPARTMENT OF THE SMALLER TANK.
3.C.INSTALL AN EFFLUENT FILTER IN THE OUTLET TEE OF THE 2,000-GALLON SINGLE-COMPARTMENT TANK.
3.D.THE TANK ARE NOT SUBJECT TO BUOYANCY.
4.ABSORPTION AREA CALCULATIONS
4.A.GROUNDWATER WAS NOT ENCOUNTERED AND THE PROPERTY CONTAINS SLOPES LESS THAN 20%. THEREFORE, BUT THE ELEVATION OF THE
SYSTEM IS HIGHER THAN THE ELEVATION OF THE SEPTIC TANKS. THEREFORE, THE SYSTEM SHALL BE A PRESSURE DOSED SHALLOW
GRAVELLESS CHAMBER SYSTEM IN A BED CONFIGURATION.
4.B.SOILS WERE ANALYZED BY BOUNDARIES UNLIMITED INC. (SEPTEMBER 24, 2017) TO BE SILTY CLAY LOAM WITH PERCOLATION RATES BETWEEN
43-70 MINUTES PER INCH (MPI) (AVERAGE = 60 MPI). THEREFORE, THE SOIL TYPE IS CONSIDERED TO BE TYPE-3 WITH A TREATMENT LEVEL 1
LONG TERM ACCEPTANCE RATE (LTAR) OF 0.35 gpd/SF FOR TL1
4.C.MINIMUM SOIL TREATMENT AREA, A:
A = ADWF = 1199 = 3,425.8 S.F.
LTAR 0.35 gpd/S.F.
4.D.SIZE ADJUSTMENT FACTORS: PRESSURE DOSED BED = 1.0; CHAMBERS IN BED CONFIGURATION= 0.7
4.D.1.A, adj = 3,425.8 SF * 1.0* 0.7 = 2,399 SF
4.E.GRAVELLESS CHAMBER SYSTEM:
4.E.1.INFILTRATOR QUICK4: 2,399 SF / 12 SF/UNIT = 200 UNITS IN A MULTIPLE BED CONFIGURATION.
4.E.2.ADS ARC36 (STANDARD): 2,399 SF / 15 SF/UNIT = 160 UNITS IN A MULTIPLE BED CONFIGURATION.
5.THIS SYSTEM IS SIZED FOR TYPICAL DOMESTIC WASTES ONLY. BACKWASH OR FLUSHING FLOWS FOR REVERSE OSMOSIS UNITES OR WATER
SOFTENERS AND/OR FILTERS SHOULD NOT BE INTRODUCED INTO THIS SYSTEM.
6.CLEAN OUTS ARE REQUIRED AT THE HOUSES/RV(s) AND AT ALL BENDS AND AT LEAST EVERY 100-FEET BETWEEN THE HOUSES AND THE SEPTIC TANK.
7.THE CONTRACTOR SHALL BE RESPONSIBLE FOR INSTALLING ALL WATER TIGHT COMPONENTS THROUGHOUT THE SYSTEM TO PREVENT INFILTRATION.
8.INSTALL RISERS AS NECESSARY TO BRING ALL ACCESS PORTS TO FINAL GRADE. PORTS SHALL BE MARKED IF CAPS ARE TO BE BURIED.
9.INSTALL 3-INCHES OF BLUEBOARD INSULATION, 3-FEET WIDE, OVER SEWER AND EFFLUENT PIPE WHEREVER DEPTH IS LESS THAN 3-FEET. UNDER NO
CIRCUMSTANCES SHALL COVER BE LESS THAN 2-FEET.
10.LOCATIONS OF ALL COMPONENTS MAY BE VARIED AS NECESSARY AS LONG AS ALL MINIMUM DISTANCES AND SLOPES MEET THOSE REQUIRED.
To Rifle
CR
#
1
1
3
NOTES:
1.EFFLUENT HAS BEEN OBSERVED TO SATURATE THE SURFACE SOILS ON ALL
FOUR (4) OF THE EXISTING ABSORPTION BEDS. THEREFORE, THE PURPOSE OF
THIS DESIGN IS TO EXPAND THE EXISTING ABSORPTION SYSTEM TO REDUCE THE
LOAD ON EACH BED. THIS WILL BE ACCOMPLISHED BY REPLACING THE EXISTING
DISTRIBUTION VALVE AND ADDING TWO (2) ADDITIONAL ABSORPTION BEDS FOR
A TOTAL OF SIX (6).
2.EXISTING SYSTEM:
THE EXISTING SYSTEM WAS CONSTRUCTED IN 2017 AS FOLLOWS:
2.1.2000-GALLON SINGLE COMPARTMENT PRECAST CONCRETE SEPTIC TANK;
2.2.1000-GALLON TWO-COMPARTMENT PRECAST CONCRETE SEPTIC TANK
WITH AN ORENCO BIOTUBE PROPAK;
2.3.PUMP: ORENCO PF3005 (30 GPM, 1/2 HP, 115V HIGH HEAD VERTICAL
TURBINE WITH DEMAND DOSE CONTROLS);
2.4.TRANSPORT PIPE DIAMETER/MATERIAL: 1-1/2"Ø SCH.80 PVC;
2.5.LATERAL PIPE DIAMETER/MATERIAL: 1-1/4"Ø SCH.40 PVC;
2.6.ORIFICE SIZE/SPACING: 3/16"Ø AT 4' 0.C.;
2.7.OPERATING HEAD AT THE DISTAL END ORIFICE: 5';
2.8.DRAIN-BACK VOLUME FROM TRANSPORT PIPE: 29 GALLONS;
2.9.FOUR (4) ABSORPTION BEDS EACH COMPRISED OF 52 INFILTRATOR QUICK4
UNITS (208 TOTAL).
3.THE DOSING SYSTEM FLOATS SHALL BE RESET ACCORDING TO THE FOLLOWING
PARAMETERS:
3.1.DOSE SIZE: 100 GALLONS;
3.2.PUMP ON TIME: 200 SECONDS;
3.3.DOSES PER DAY: 12
3.4.CONTACT SCG ENTERPRISES AT 303.697.9404 OR VALLEY PRECAST, INC.
AT 719.395.6764 FOR SYSTEM SPECIFICATIONS AND ADJUSTMENT
PROCEDURES)
BOTTOM TO BE LEVEL AND FLAT OVER ENTIRE
AREA TO WITHIN 0.1'±. (TYP.). IF NECESSARY
TO ACHIEVE THIS SURFACE, IMPORT CONCRETE
SAND TO USE AS LEVELING MATERIAL. REMOVE
ANY ENCOUNTERED BOULDERS AND BACKFILL
WITH LOAMY SAND OR SANDY GRAVELS. DO
NOT USE COMPACTED MATERIALS.
GENERAL ABSORPTION AREA NOTES
1.INSTALL CHAMBER UNITS IN ACCORDANCE WITH
MANUFACTURER'S RECOMMENDATIONS.
2.ABSORPTION BEDS SHALL NOT EXCEED 12' WIDE BY
100-FEET IN LENGTH, SHALL PARALLEL THE
TOPOGRAPHY AND SHALL BE INSTALLED IN A
RECTANGULAR PATTERN WHENEVER POSSIBLE.
3.THE BOTTOM OF THE ABSORPTION BED SHALL BE
LEVEL AND THE BOTTOM AND SIDEWALLS MUST BE
RAKED TO REMOVE ANY SOIL SMEARS INCURRED
DURING THE EXCAVATION. FAILURE TO DO SO MAY
REQUIRE THE CONTRACTOR TO REPLACE THE
ABSORPTION FIELD AT HIS/HER OWN EXPENSE.
4.DRAINAGE SWALES ARE TO BE PROVIDED ABOVE AND
AROUND THE FIELD, AS NECESSARY, TO PREVENT
SURFACE RUNOFF FROM ENTERING ABSORPTION
AREA.
5.NO EXCAVATION OF THE ABSORPTION FIELD IS TO BE
DONE DURING WET WEATHER AND USE OF RUBBER
TIRE VEHICLES OVER THE ABSORPTION AREA IS
STRICTLY PROHIBITED.
6.UNSUITABLE MATERIAL EXISTING WITHIN THE FIELD
SHALL BE EXCAVATED AND BACKFILL SHALL CONSIST
OF IMPORTED LOAMY SAND OR SANDY GRAVEL. THE
ENGINEER SHALL BE CONTACTED IF BEDROCK OR
GROUNDWATER IS ENCOUNTERED IN THE
EXCAVATION.
7.TOPSOIL COVER MAY BE VARIED (1-FOOT MINIMUM,
2-FOOT MAXIMUM) TO ALLOW FOR LANDSCAPING.
8.WHEN MULTIPLE BEDS ARE USED, BEDS SHALL BE
SEPARATED BY 6-FEET MIN. OF UNDISTURBED SOILS.
4"Ø PERFORATED PVC PIPE.
EXTEND PIPE TO REST ON
BOTTOM OF THE BED
COVER WITH 6" OF TOPSOIL
AND REVEGETATE
12
"
M
I
N
.
,
24
"
M
A
X
.
INSTALL A 12"Wx24"L SPLASH
BLOCK BELOW EACH INLET PIPE
GRAVELLESS CHAMBER SYSTEM:
INFILTRATOR QUICK 4, ADVANCED
DRAINAGE SYSTEMS ARC36 (STANDARD),
OR ENGINEER APPROVED EQUAL.
FILL OVER THE CHAMBERS
WITH UNCOMPACTED WELL
GRADED LOCAL SOILS.
4"Ø COUPLING (UNION). USE A
HOLE SAW TO CUT OUT CIRCLE
OFF THE CENTER OF THE UNIT
STANDARD INSPECTION PORT, TYP. (4"Ø PVC
SOLID PIPE CUT TO FIT. LOCATE PER PLAN
VIEW. ATTACH REMOVABLE CAP OR
THREADED CLEANOUT ASSEMBLY.
CIRCULAR IRRIGATION-STYLE VALVE
BOX & COVER - LID COLOR PURPLE
OR GREEN - LABEL "SEWER"
Scale: N.T.S.
Gravelless Pressure Dosed Chamber Absorption Bed
1-1/4"Ø PRESSURE DOSING PIPE
WITH 3/16"Ø HOLES DRILLED EVERY
4' O.C., FACING UP, AND ONE (1)
HOLE FACING DOWN AT THE END OF
EACH TRENCH (FOR WEEPING).
INSTALL A 12" PAVER OR SPLASH
STONE BELOW THE DOWN FACING
HOLE TO PREVENT SOIL EROSION.
COVER THE CHAMBER UNITS WITH A NON-WOVEN
FILTER/LANDSCAPE FABRIC TO LIMIT FINE
MIGRATION INTO THE CHAMBERS