HomeMy WebLinkAboutOWTS Design5020 County Road 154
Glenwood Springs, CO 81601
phone: (970) 945-7988
fax: (970) 945-84s4
email: kaglenwood@kumarusa.com
An Employcc O,Yncd Compony www'kumarusa'com
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
September 15,2020
Igor & Elena Skakovsþ
5165 County Road 331
Silt, Colorado 81652
sigorco@hotmail.com
Project No. 20-7-385.02
Subject: Preliminary Onsite W'astewater Treatment System (OWTS) Design, Proposed
Residence, Lot 5, Filing 3, Mineota Ridge Estates, TBD Mineota Drive, Garfield
County, Colorado
Dear Mr & Mrs Skakovsky:
As requested, we are providing preliminary recommendations for an onsite wastewater treatment
system (O\I/TS) at the subject site. The services were verbally authorized by you on
September 1, 2020 and are supplemental to our proposal for professional engineering services
dated June 30, 2020 . This letter provides our preliminary design of the system based on the
current Garfield County Onsite Wastewater Treatment System Regulations and Colorado
Department of Public Health and Environmental Regulation {143. We previously conducted a
subsoil study for foundation design ofthe proposed residence at the site and presented our
findings in a report dated August 10, 2020, Project No. 20-7-385.
The preliminary design is needed for coslbudgeting of the OWTS. The proposed residence will
be a five-bedroom, single-story structure located on the lot as shown on Figure l. Ground floor
of the residence will be slab-on-grade. The proposed OWTS soil treatment area (STA) will be
located to the northwest of the residence.
Based on the site conditions and the subsoils encountered in the borings, the soils on the site are
assumed to be Clay Loam with an assumed long-term acceptance rate (LTAR) of 0.35 gallons
per square foot per day. The STA has been sized for five bedrooms (eight people) and an
average daily flow 75 gallons for a total of 600 gallons per day. The STA will consist of
4 trenches with 25 Infiltrator Quick4 Plus Standard chambers in each trench for a total of
100 chambers. The STA size calculations are provided on Figure 2. T.he effluent will gravity
flow from the residence to the septic tank for primary treatment and then gravity flow to the STA
for dispersal and final treatment. Equal distribution will be provided to the STA by a Tuf-tite
6-Hole distribution box. The septic tank should be a Valley Precast 1,500 gallon, two-chamber
Igor & Elena Skakovsþ
Sçtember 15,2020
Page2
se,ptic tank. A det¿il for the tank is attached. If a separate grey water tank is planned it can
consist of a'similar tank for preliminary design. A preliminary layout of the systøn components
is shown on Figure 1.
A design re,port, which will need to include profile pit tactile evaluations of the subsoils at the
STA, will be needed for the County permitting and the installation of the OV/TS. If you have
any questions, contact us.
Sincerely,
Kumar & Associates, Inc.
Shane M. Mello, Staff Engineer
Reviewed by:
David A.
SMM/kac
P
attachments
cc:Giard Homes - Roger Giard (roger.qiard@.eiardhomes.com)
Figure I - Preliminary OWTS site plan
Figure 2 - Soil Treaünent Area Calculations
Valley Precast 1,500 Gallon, Two-Chamber Septic Tank Detail
Kumar & Associates, lnc. @ Project No. 20-7-385.02
VICINITY MAP
SCALE: 1 "=500'
MINEOTA DRIVEl\
--+1=---f--
aa""(o
t-o
-l
LOT 5
T
t-oJ
-/
TUFTITE 6=HOLE
DISTRIBUTION BOX
PROPOSED VALLEY PRECAST
1,500 GALLON TWO
CHAMBER SEPTIC TANK
CLEANOUT,/
//'BORING - -,t-
-/
PROPOSED SOIL TREATMENT
AREA (STA) CONSTSTING OF 4
ROWS OF 25 INFILTRATOR
QUICK4 PLUS STANDARD/
CHAMBERS (1oo CHAMBERS
ou*'- --"'//LOT 5, FILING 5roTAL). --, MINEOTA RIDGE ESTATES -/
TBD MINEOTA DRIVE
',,,a'
¿- ¿ ¿/'
/--/
_/
¿--
f NGBORI,t
SCALE-FEET
6695¿
PRELIMINARY OWTS SITE PLAN Fig 120-7 -385.02 Kumar & Associates
OWTS SOIL TREATMENT AREA CALCULATIONS
In accordance with the GarfleH County OWTS Regulations and the Cobrado Depaftment of Public Heallh
and Environment's Regulation #43, the soiltreatment area was cabulated as foþws:
CALCUTATION OF OWTS DESIGN FLOW:
q = (F)(N)
N = 2 PERSONS PER BEDROOM FOR FIRST 3 BEDROOMS
AND 1 PERSON PER BEDROOM FOR EACH ADDITIONAL BEDROOM
WHERE:
Q = DESIGN FLOW
F = AVERAGE FLOW PER PERSON PER DAY
B = NUMBER OF BEDROOMS
N = NUMBER OF PERSONS
þ=
$=
N=
Q=
75 GALLONS PER DAY
5 BEDROOMS
8 PERSONS
600 GATLONSPERDAY
CALCULATION OF OWTS SOIL TREATMENT AREA:
MINIUMUM TREATMENT AREA = Q + LTAR
WHERE:
QE
LTAR (SOIL TYPE 3) =
600 GALLONS PER DAY
0.35 GALLONS/FTTDAY
MINIMUM SOII TREATMENTAREA =
REDUCTION FACTOR FOR CHAMBERS =
MINIMUM SOII TREATMENTAREA WTTH REDUCTION =
t7r4.3 SQUARE FEET
0.70
1200 SQUAREFEET
AREA PER INFILTRATOR QUICK 4 STANDARD CHAMBER =
TOTAL CHAMBERS NEEDED =
12 SQUARE FEET
1OO CHAMBERS
NUMBER OF TRENCHES =
CHAMBERS PERTRENCH =
TOTAT NUMBER OF CHAMBERS AS DESIGNED =
4 TRENCHES
25 CHAMBERS
1OO CHAMBERS
TOTAT SOIL TREATMENTAREA =1200 SQUAREFEET
20-t-385.02 Kumar & Associates SOIL TRTATMENT AREA CALCULATIONS lis, 2
íSOO Gallon Top Seam -2CPlbm #
l500t 2GP
DESIGN NOTESr Design per performonce test per ASÏ[,1
c1227
r Top surfoce oreo 62,33 ft2
¡ f'c GD 28 doys; concrete = 6,000 PSI
Min.
lnstollotíon:
¡ Tonk to be set on 5" mín. sond bed or
peo grovel¡ Tonk to be bockfilled uniformly on oll
sides in lifts less thon 24" ond
mechonicolly compoctedr Excovoted moteriol moy be used for
bockfill, provided lorge stones ore
removed¡ Excovotion should be dewotered ond
tonk filled with woter prior to being put
in service for instollotion with woter
toble less thon 2' below grode¡ Meets C1644-06 for resilient connectors¡ lnlet ond Outlet identified obove piper Delivered complete with internol piping
¡ 4' Moximum bury depth
t-
.-r.u
Top
View
I tClü46
6r ìn
:1 rnr< Irol
1=.
Rlsel¡bGnade
Boot Rubber
Sælent
6i 3n
5l ln
Section
View
Digging Specs lnvert Dlmensions Net Copocity Net Weight
13' Long x I' Wide lnlet Outlet Length width Height lnlet Side Outlet Totol
:Lid
I
1
3600 lbs 11
I
I
Tonk Totol
56" below inlet 56"53"132"68"68 1002 gol 507 gol 1509 gol 1180 lbs 14780 lbs
ALLOWABLE BURY
(Bosed on Woter Toble)
WA'IER TABLE ALLOWABLE
FARTH FILL
0'-o"3'-0"
1' - 0"3'-0"
2'-O'4'-O"
3'-0"4'-0"
DRY 4'-O"
Phone: 719€95{70¡l
Fax 719€95-87?
Web¡lb: www.valleyprcætæm
Emll : fionüeek@t¡d leyprcætæmBue¡¡ Vbta, Colorado
n PRTCAS[¡rnc.