HomeMy WebLinkAboutOWTS Design Report 11.17.2017PERCOI..ATION TEST AND
ON-SITE WASTEWATER TREATI'IENT SYSTEM DESIGN
13100 couNw RoAD 204
DE BEQUE, CO
Prepared For
Golorado Bullding Systems
Prepared By:
CAPSTONE
ENTFRPRISES WEST,LLC
GEOTECHNICAL AND MINING ENGINEERING
TESTING AND INSPECTION SERVICES
óI8 PARTEE DRIVE
GRAND JUNCTION, CO 8I5O/*
PHoNE (970) 250-5551
marti n@capstonewest.com
t{ovember 17,2017
JobNo.4142
CAPSTONE
ENTERPRISES WEST,LLC
GEOTECHNICAL AND MINING ENGINEERING
TESTING AND INSPECTION SERVICES
óI8 PARTEE DRIVE
GRAND JUNCTION, CO 8I5OI'
PHONE (970) 250-5551
marti n@capstonewest.com
November t7,2OL7
JOB # 4L42
Attn:Mark Dearth
Colorado Building Systems
Grand Junction, CO
Subject:Percolation Test and On-Site Wastewater Treatment System Design,
13100 County Road 204
At your request, on October 23,20t7 Capstone Enterprises West, LLC directed and observed the
excavation of three test p¡ts to evaluate onsite soils for design of an On-Site Wastewater
Treatment System (OWTS). The suitability of soils was evaluated by performing a percolation
test, as prescribed by the Garfield County regulations.
The results of the percolation test and the OWTS design are presented in this report. lf you
have any questions, or if we may be of further assistance, please do not hesitate to contact us.
Respectfully Submitted :
CAPSTONE ENTERPRISES WEST, ttc
Martin W. Chenoweth, PE
Registered Professional Engineer
MWC
37784
2
PERCOI.AT¡ON TEST
Per your request, Capstone Enterprises West, LLC performed a percolation test for your
proposed building site. The test was performed as prescribed by the Garfield County
regulations updated on April 21,2014.
The site is in the east half of the southeast quarter of section 25 Township 6 South
Range 99 West. The following map shows the general location'
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The property is made up of 2 40-acre parcels that is a combination of irrigated farm land
and undisturbed wilderness. The construction site will be in the farmed land. The
following images show the property limits and the proposed building site.
.Pt
,&<.,.
3
The proposed building site is in the irrigated land. This field slopes gently to the south at
approximately 4o/o. The following image shows a detail of the proposed building site and
the location of the test pits (TP) and the percolation holes (PH).
4
The OWTS investigation was performed at the same time as the geotechnical
investigation for the foundation recommendation. Test pit TP1 was excavated to
as the profile hole for the OWTS design. The profile hole was excavated to a
depth of 9.0 feet (excavator refusal). Free water was not encountered nor was
there evidence of a seasonal high-water table. The geologic log is presented on
the following page.
q
PROFILE HOLE GEOLOGY
Tp-1
0
TOFSOIL- Clay w/ Roo*
Lt Brn- Silty Clay
$fteetwash Sravels
Thin Flat Fragments
10
A total of 3 perk holes were dug to evaluate the percolation rates in the shale. All
holes were moisture conditioned as prescribed by Garfield County regulations.
I
2
3
4
5
6
7
I
I
6
The percolation test was performed 24 hours after the initial conditioning. The
results for the percolation test are presented on the following pages.
PH-1
Ëlapsed
Time
Cumulative
Drop
Percolation
Rate
Ultimate
Perc
Rate
Design
Perc
Rate
L+30"0
30
60
90
L20
0.00
3.63
6.50
8.50
12.00
8
9
L1
10 10
1.1
PH.2
Elapsed
Time
Cumulative
Drop
Percolation
Rate
Ultimate
Perc
Rate
Design
Perc
Rate
14-30"o
30
60
90
L20
0.00
r.75
3.00
4.50
6.00
L7
20
20
2A 20
20
PH-3
Elapsed
Time
Cumulative
Drop
Percolation
Rate
Ultimate
Perc
Rate
Design
Perc
Rate
1ll.30"0
30
60
90
t20
0.00
1.38
2.50
3.50
s.50
22
24
26
22 22
26
1
2û
la
16
i.4
----- Lifiìits
--
PH-l
_- PH-2
PH"]
-Ò--a"-
20
Water Drop Vs Ïime
0J
!J
o-oL
CJ
fı
i1
0L
t)
4
2
0
U 40 6e¡ 8û
Ilapsed Time {rninutes)
1.0i1 12û
I
All three perk test holes absorbed water within the prescribed limits (greater than
5 minutes per inch and less than 60 minutes per inch). The average of the last
half hour of the two-hour test was 17 minutes per inch. Based on the results of
the percolation test and the Garfield County Guidelines, the system has been
designed based on a Long Term Acceptance Rate (LTAR) 0.60.
Teble f0-1 Level
Shaded a66 oqulÞ syc6m daign by I prôfe$longlcnginæ¡'
TEatrc¡t l6.r¡s sÉ deliæd ¡n Trble 6-3.
untiñ€d ß¡nd fileE ¡n lhose sotltypo! ghSll provids pelhoggn mofl. lbÊlgn shall confom to sdim ll c.z.q uñl¡nod s¡nd F¡fiæ
. Htsh€r tong-tem æccfle¡6 rat6 fq l@fmnt Lsvst 3N may be ¡llq/id lor OWTS nqu¡Þd to haw s d¡rch¡rgs prm¡, if ltn qpabilily ol lhe dsslgn to achi€w 3 hlghol
long.l.m d@ple@ Etê €n be sub6tantitt€d
sdl TYps,fort¡Þ, St,uctw rnd P.rol.aid Ralc Ra¡gð
Lorlg-l¡m Acc¡pa¡H R.Þ (LTARI;
Od¡oE p€r d.y pÍ lqu¡rê fæt
Soil
Type UgOA Soll fô¡tuÞ
uSoASoil
Sl¡uohn-
frhrp!
ugDA 8óll
8lruc{uE.
Cnd¡
Feftol¡llon
tuÞ(tPll
lntbnıl
Lewl f I fralnant
LPal 2t
lmtmil
Lwd 2ll!
fuürfil
bv¡l gr
ÌEaùtsil
Lwel 3llr'
0
gonTy¡c r r|$ mm
ü¡n 3C9ß Rocl( (>zmm)i
Sollly!.r2{$ümD
ttrã t096 Rodr (>ânml
0 (8ln¡L
Gnlîl <5
f¡Hîünm
3-tbôt dr.Þ
uillßd
¡¡nd lllt r
nqulnd¡
Mhkn ñ 2-tbol dd¡ uìilmd nrÉ iùt Ëqt¡trd
Sand, Loamy ssnd 0 sr5 0.Eo r.?6 1.2a 1.10 1.40
2 slndy LM, Ltrr, sll
Lom
PR
(Prbrl¡tic'
ÊK
(Blod(V¡
GR
{geub¡)
2 (Modˡe)
3 (Süûno)rÈ35 0.80 0.00 03t 1.00 t.@
2A Sandy L@. LoEm. S¡lt
Lorm
PR, BK.
6R
0 (rcne)
I (Weák)
Meslw 2€4)&50 o.70 o.70 0.r0 0.60
3 Srndy
Lom
Cl¡y
Sily
Lom. Clay
Cl¡y Lo€m
PR, BK,
GR 2,3 4160 035 0.60 0.Eo 0,60 0.€0
3 $nûychylam,e,hy
l-o¡r!,8lþC¡y l¡tî
FR. BI(,
€R
0
tHblYl 6t-75 0.90 O.¡al,0.40 0r0 o.tt
a $¡n{y chr, ohy, srt
Cl¡t
Pñ, FK
oÊ ¡,3 7ù00 0.20 0.30 '0.30 030 ol0
a
g.ndt Clrt, C¡r, tlltc¡v
Pn, rl(
6R
0
I
llhl.hr 9r¡20 0.r!o.20 0-20 0¿0 0.20
6 tol¡Ïyprr ¡.a F{¡lt 1,2,3 l¡t.0.10 0,t6 0.1ó o.tı 0.lg
NOTE;
1
2
9
WASTE WATER TREATMENT SYSTEM DESIGN
A single dwelling is planned for this site (-2,000 square feet). The residence at
this site is planned to be a three (3) bedroom dwelling. Using the guidelines in
the Garfield County On-Site Wastewater Treatment System (OWTS) Reoulations.
Effective Date: April 21 ,2014, (OWTSR) the following sewage flow calculations
were prepared:
MAIN HOUSE
Base flow 150 gallons per bedroom * 3 Q =450 gal lday
Once again using the OWTSR the absorption area was calculated.
Where: A = Absorption Area in square feet
Q = Design Flow of sewage in gallons/day
LTAR = Long Term Acceptance Rate (From Table 10-1,)
o 450
AREA =LTAR 0.6 =750sqft
Base Area
Size Adjustment Factors
Gravity
Rock
Total Absorption Bed Area
750 sq. ft.
1.2
1.0
900 sq. ft.
A single l2footwide by 75 foot long absorption bed will be needed along with a
1,000 gallon sept¡c tank. The design details are attached.
10
1REV6t8t17DATEAdded EasementsDESCRIPTIONVIWCBYCKCAPSTONÊENTERPRISESó18 PARTEE DRIVEGRAND JUNCTION, CO 81504PHoNE (970) 250-s55tma rtin@capstonewest,comWEST,LLCBY MWCHENOWETH1'lt17t17PROJECT NO. 4142SHEET NO. 1 OF3scALE 1"=50"OWTS GENERAL LAYOUT13100 COUNTY ROAD 204355 rr351 t'r¡å2S lo f:e * 4a/aI'rt:rrJ J'..,,WELLT00' os
REVInspection PortsPerforated ¡n GravelCapped 12" Above Ground4" PERFORATED DiSTRIBUTION LINES6" GRAVEL UNDER. 2" GRAVEL OVERFILTER FABRIC OVER GR,AVEL1.0" - 2.5'CLEAN ROCKUNCOMPACTED SOIL CAP(MOUND 5olo)1.01.03.0BED IN SECTIONEFFLUENT TN71Inspection Ports3DATEDESCRIPTIONBYCKCAPSTONFENTERPRTSESWEST,618 PARTEE DRIVEGRAND JUNCTION, CO 8I5OôPHoNE (970) 2s0-355tmartin@ca pstonewest.comLLCPROJECT NO. 4142BY tr¡ w cxElowern11117t17OWTS CONSTRUCTION DETAILS13100 COUNTY ROAD 204SHEET NO. 2oF3SCALE NTS
REVFloor ElevationExisting Ground976.5EFFLUENT LINE.3%DISCHARGE LINE -3%4" SCH 401,000 Gal tankScale (feet)DATEDESCRIPTÏONBYCKCAPSTONÈENTERPRTSESWEST,óI8 PARTEE DRIVEGRAND JUNCTION, CO 81504PHoNE (970) 250-5551mart¡n@capstonewest.comLLCPROJECï NO. 4142BY MWCHENOWETH'l1t17t17OWTS SYSTEM PROFILE13100 COUNTY ROAD 204SHEET NO. 3oF3scALE 1.=15'