HomeMy WebLinkAbout1993-12-10 Septic System Design ReportS-P TESTING, INC.
Steven B. Schirmers — MPCA Cert. N,o. 627
Coffin Site
Lot 2, Block 1
Orono, Henn. Co., MN
951 Katydid Lane NE • St. Michael, MN 55376 • (612) 497-3566
December 10, 1993
This On -Site Sewage Treatment System is Designed for a Type 1, five
bedroom home in accordance with the Minnesota Pollution Control
Agency Chapter 708C and local ordinances.
The soils on this site are SCS soils mapped - KkB - Kilkenny
loam. A seasoriall}l hich water table was located at 22" to 44",
(mottled soil). Cue to i.iit aeas3null h h otnr *�h��; a
Pressurized Mound system will need to be installed. The bottom
of the rock bed :rust be located at least 3' above the seasonally
high water table.
The future expansion is at: the bash of a slope and to keep the
absorption area of the mouri-? 75' from a wetland, approximately
1/3 of the upslope portion of the mound will be or, 6 to 8% slope.
This will need tc he approved by city officials and rust remain
future expansion ::n!y.
The soils at a depth of 12" have a percolation rate averaging
6.8 min /inch.
A pumping chamber will need o be installed to lift the effluent
to the treatment area.
_.ie manifold and supply line pipe must have back drainage to the pumping
chamber. The distribution pipes shall Have their ends capped. Be sure
the rock and sand fill material are clean. The sod layer below the
entire mounded area must be turned over, just break up the sod, be sure
not to over work.
The power supply and switches must be located outside the manhole an,'
pumping chamber in a weather proof enclosure. A warning dt-!vice must
be installed with a light and sound device, this is in case of a pump
failure. Mercury floats are a qood method.
Lot7,Blk.1
Coffin site
Orono
(2)
All neighboring wells are located greater than 100' away from the
proposed treatment area.
KPPp all heavy equipment off of the proposes treatment area before and
after construction. The treatment area should be marxed off before
construction. This Design is not valid & the System will need to
be relocated if failure to protect the areas proposed for On -Site
Sewage Treatment occurs.
With proper installation and maintenance, this system should have no
Problem in treating septic effluent effectively.
Nr,thing other than fray water, (laundry, showers, etc.) human
waste & toilet tissue should be disposed of into the septic tanks.
-arbage disposals are nc,t recommended. Smaller amounts of laundry
soaps, dish soaps, cleaning agents, etc. are better for the system.
Antibacterial soaps & chlorine agents ma- -
kill the bacteria needed
to treat septic effluent properly. Additives are not recommended,
they f,ic-y cause harmful damage to your system. Recommend to pump
& clean your tanks by a certified pumper every year if you have
1 tank & every 2 years if you have 2 tanks to insure proper
maintenance.
Steven B. Schirmers
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MOUND DESIGN WORKSHEET
(For Flows up to 1200 gpd)
A. FLOW
Estimated 0 gpd (see pages D-7 or I-3, 4, 5)
or measured -- gpd x 1.5 = _ -
B. SEPTIC TANK LIQUID VOLM IES
j-ta,SO4 l -Too gallons (see pa jes C-3 or C-5)
C. SOILS (refer to site evaluation)
1. Depth to restricting layer = -3 c.l'fv �io inches
2. Depth of percolation tests inches
3. Percolation rate L. 9 mpi
4. Land slope %
Eaitnxk4 Seurage Flow in Gallons pa day
(aw)
Number
or
Type I
Type 11
Type III
Iledraolns
i V
2
300
225
ISO
3
450
300
218
♦
600
375
256
l6n.
.r.p
5
6
750
900
450
525
294
332
L
7
>f
1060
12W
600
675
370
409
to
.��.
tiydc T•d C.p.. a:� M a.14...
lie*s &mb.W d,.w..l
2.r Yr
750
1125
3 ar a
1010
15W
♦ a 6
131D
2250
D. ROCK LAYER DIMENSIONS
1. Multiply flow rate by 0.83 to obtain required area of rock
layer: Daily Flow x 0.83 =
f)SO gpd x 0.83 sq. f t. / gpd = C,a .� sq. f t.-H o'5 (oY 4
2. Select width of rock layer (10 feet or less) _ / 0 ft.
3. Length of rock layer = Area + Width =
v Ll sq. ft. + i p ft. = (, i� ft. Rock Bed
♦;t 1.,.. �•,..��l�ti.•. ti tis
E. ROCK VOLUME `-�f•. ng f.f.'.f.'.�.•
Length
1. Multiply rock area by rock depth to get cubic feet of rock;
4z-j�a sq. ft. x L. . ft. = 21.E cu. ft.
2. Divide cu. ft. by 27 cu. ft./cu. yd. to get cubic yards;
r) I V cu. ft. + 27 = -a 1) cu. yd.
3. Multiply cubic yards by 1.4 to get weight of rock in tons;
III cu. yd. x 1.4 ton/cu. yd. = _Z!1e tons.
F. ADSORPTION WIDTH e-1- A L4 �-o t4
1. Percolation rate in top 12 inches of soil is mpi
2. Select allowable soil loadinfi rate from table on page E-,
4 N gpd/ ft2
3. Calculate adsorption width ratio by dividing rock layer
loading rate of 1.20 gpd/ft2 by allowable soil loading rate;
1.20 gpd/ft2+ , �z,/ gpd/ ft2= ) � L.
Check this value on page E-16.
4. Multiply adsorption width ratio by rock layer width to get
requires: adsorption width;
Absorption Width Sizing Table
pervolsdollRr
is M-1-pv
Gnh IMP l)
Soil Teslure
Gallom
pu dey per
puan Lela
Raiool
AbwWien width
to Reek Layer
Width
Fa.1er 11M 0.1
Coraa Sand
----
--•-
0.1 IDS
Surd
1.20
1.00
0.110300
run Sand ••
0.60
2.00
64015
Sally laent
0.79
1.52
16 to 30
I.eara
0.60
2.W
31 D 45
Sik I. hm
2.40
461060
Coy Leotn
12
�lS
2.67
60 to 120
Clay
0.2♦
5.0U
Slower than
Clay
---
120'
F
U. DOWNSLOPE DIKE WIDTH
I. If landslope is 3% or more, subtract rock layer width from
adsorption width to obtain minimum downslope dike toe for
absorption: -
ale ft - /0 ft = 19 feet
2. Calculate minimum mound size based on geometery:
a. Determine depth of clean sand fill at upslope edge of rock
layer: Separation /, U feet
b. Multiply rock layer width by landslope to determine drop
in elevation; Slope Difference
1Q x _-LL% + 100 = . L4 feet ��-�-
c. Add depth of clean sand depth of clean sand for "" -+ 6.•P o.._.
separation at upslope edge (2a) to depth of rock layer to .
rock depth and the depth of cover to find the total mound
height at upslope edge of rock layer;
l ,y ft + 1 ft + 1 ft = • O feet
d. Enter table on page bottom with landslope and upslope
dike ratio. Select dike multiplier of 3.1-1 S
e. Multiply dike multiplier by upslope mound height
to get upslope dike width: ? . 0 x 3. � < = / n feet
f. Add the depth of slope difference (2b) to the upslope
height to get the downslope height
3.0 +-LI_=:?.Vfeet
g. Enter table on page bottom with landslope and
downslope dike ratio.
Select dike multiplier of 4. e
h. Multiply dike multiplier by downslope mound height
to get downslope dike width: , . L x y.,)c- _ I_ feet
i. Compare the values of step G.1 and Step G.2.h. Select the
greater of the two values as the downslope dike width;
1') feet
j. Total mound width is the sum of upslope dike
width plus rock layer width plus downslope
dike width;
ft + )0 ft + 12 ft = _feet vq1�
k. Total mound length is the sum of upslope
dike width plus rock layer length plus
upslope dike width;
�- ft + ;e ft + _1J-- ft = 4/ `�_ feet
10 , -r E t ) Ali
/ .2
3:1
{:1
wns op
5:1
6:1
7:1
3.1
6:1
pslope
S:1
i l
7:1
4:1
t Yope
0
3.0
4.0
&0
60
70
30
4.0
So
60
70
60
1
3339
4.17
5.26
639
7 53
: 91
3 M
476
566
654
7.41
2
3.19
4.33
S 56
682
314
: %3
370
! 54
536
6.1!
6.90
3
330
4U
SM
732
M.Y.
"•
435
Sng
5.79
64S
ti-
5
3.53
S W
i u)
F I.
..
6
366
5.26
7.14
9 1e
1 .7
a
3 :3
3 .%5
4 :1
! 93
5 ! 1
7
310
5.56
70
1034
13 .73
2 s.;
3 12
3.70
4 2.3
! 70
5.13
a
3.9S
S.M
115!
17
242
3.03
357
{OS
49
{6
9
6.11
&
09
M
19
54
216
294
345
390
4.30
11
10
29
6.6
100
IiM
17
1.12
!!
11
4a
7.14
111
17'6
271
323
361
395
42ti
2
469
7.9
1-1
21 41
312
7:4
351)
4ei+
C
A. Determine Pump caPadhr
Gravity Distribution
1. Minimum suggested is 600 gallons per hour (10 gpm) to stay ahead of
water use rate.
2. Maximum suggested for delivery to a drop box of a home system is 2,700
gallons per hour (45 gpm) to prevent build-up of pressure in drop box.
Pressure Distribution
3. a. Select number of perforated laterals 3
b. Select perforation spacing = 9_ ft.
c. Subt 2 fL from the rock layer length.
-2ft.= f.(. h.
d. Determine the number of spades between perforations.
Length perf. spacing ft. + ft. = 3 spaces
e. _1Z spaces + 1 =_ perforations/lateral
f. Multiply perforations per lateral by number of laterals to
get total number of perforations.
�3 x Q _ _�-7 perforations.
$ rl
x 1. gpm.
SELECTED PUMP CAPACITY _3f'! gpm
B. Determine head requirements:
1. Elevation difference between pump and point of discharge.
Z0 feet
2. If pumping to a pressure distribution system, add five feet for pressure
required at manifold
feet
3. Friction loss
a. Enter friction loss table with ppm and pipe diameter.
Read friction loss in feet per WO feet from table.
F.L. = a. L ft./100 ft of pipe
b. Determine total pipe length from pump to discharge
point. Add 25 percent to pipe length for fitting
loss, or use a fitting loss chart. Equivalent pipe
length -1.25 times pipe length =
aL i x 1.25 - l S 6 feet
c. Calculate total friction loss by multiplying
friction loss in ft/100 ft by equivalent pipe length.
Total friction loss = D .1. x ) S (� +100 = _ feet
4. Total head required is the sum of elevation difference,
special head requirements, and total friction loss.
Zv + <- + L_
(1) (2) (30
TOTAL HEAD ";L-fl- feet
C. Pump selection
1- A pump must be selected to deliver at least ,"/ gpra (Step A)
with at least '31,02_ feet of total head (Step B).
- D PCWWATION OF A PERFORATED LATERAL
feark IN rw-
won s ed
TABLE OF PERFORATION DWHARGES W CPM
Head Perforation diameter (Inches)
1 Aa
0.36
0.74
is
0.69
M90
2.0b
DAD
1.01
23
0.09
1.17
3.0
0.96
12S
4.0
1.13
1.47
3A
1.26
145
aUse 1.0 foot of head for residential systems.
bUse 2.0 feet of bad for other astablWwwats
(ripe Length
Point of Discharge
I
/pfZElevation Difference
P"'np �9
F-18b
1.5 inch 2.0 inch 3.0 inch
Sprn Fri tom ra 100 n of pips
10
0.69
0.20
12
0.96
0.28
14
1.28
0.38
16
1.63
0.48
18
2.03
0.60
20
2.47
0.73
0.11
25
3.73
1.11
0.16
30
5.23
1.55
0.23
35
7.90
2.06
0.30
40
11.07
2.64
0.39
45
14.73
3.28
0.49
50
3.99
0.58
55
4.76
0.70
60
5.60
0.82
.. c v v 1.
Location or Project Lot 2, Block 1, Coffin site, Orono
Borings made by S-P jesting, Inc. Steve Schirmers Date 12-6-93
Classifiction Sy3tem: AASHO USDA-SCS X Unified Other
Auger used (check two): Hand X or Power Flight , or Bucket X
Depth, Boring number _ 1 Depth, Boring number 2
in in
feet Surface elevation 974.6 feet Surface elevation 976.7
J -F 0 - - - -
2 -
3 -
E.=
5 -
7 -
3 -
Topsoil dark brown
loam
0 - 2'8"-MOTTLED 2'8"
Rusty dark brown loam
2'6" - 3-1/2'
Rusty olive brown
clay loam
3-1/2' - 4-1/2'
Rusty olive gray clay loam
4-1/2' - 5'
Find of boring at 5' Coot.
_ inding %:ate: -.i: ! .
present at • .aet of depth,
hours after borinq.
N-t r,re5, ,._ in hole X
t•lottlej :c,il.
Observed at 2'8" feet of depth.
Not present in hole
Comments:
2 -
3 -
Topsoil dark brown
loam
0 - 2'2"-MOTTLED 212"
Rusty olive brown
clay loam
2'2" - 3'10"
4 - Rusty olive brown loam
3'10" - 4-1/2'
Rusty olive brown sandy loa
4-1/2' - 5'
5 -
6 -
8 -
Fnd h ,ring at _l' foot.
1t .:... water tali.
present at 4-1/2' feet of depth,
19 hcurs a.-er boring.
Not present in hoi. _
Mott.e-: soil.
Observ•-d at 2"2" feet of depth.
riot present in hule _
Comments:
I
Location or Project Lot 2, Block 1, Coffin site, Orono
Borings made by -P vesting, Inc. Steve Schirmers Date12-6&10-26-93
Classifiction System: AASHU_ USDA-SCS X Unified ; Oth
Auger used (check two): Hand X or Power Flight , or Bucket X
Depth, Boring number 3 Depth, Boring number 4
in in _
feet Surface elevation 975.2 feet Surface elevation 1010.7
0 - -- — — 0
1 -
Topsoil dark brown
loam
1 _
Topsoil dark brown
loam
0 - 11209
ark 1'2" _ 1-1/2' br?wgmclay
0 - 1-1/2'
- 1'10"-MOTTLED
Brownl8aAyl-1/2'
2
1'
0"
2 -
Brown clay loam
Rusty olive brown
3 -
clay loam
3 _
1-1/2' - 3'-MOTTLED 3'
Rusty olive brown
1110" - 3'4"
clay loam
4 -
Rusty olive brown
loam
4 _
3' - 4'4"
RuF*.v olive brown silty
5 _
314" - 5'
5 _
_.'4" - 51 clay loam
_i
6 -
7 -
End of boring at 5' f-et.
Etan-ling -ate
present at aet of depth,
___ hours a'_er boring.
Not pres:,-it i:. —X__
;•tot sci 1:
Observed at 1'10"
:.et oI depth.
Not present. in 1
Comments:
6 -
7 -
H -
End of boring at 51 feet.
present at feet of depth,
hours after borin,-;.
Not present in hole _M
Mottled so. _ .
ObsArved at 31 feet of ci•:�pth.
Not present: in hole
Comments:
Lbeation or Project Lot 2, block 1, Coffin site, Orono
Borings made by S-p resting, Inc. Steve Schirmers Date 10-26-93
.Classifiction System: AASHO USDA-SCS X Unified Other
Auger used (check two): (land X or Power , Flight o-. Bucket X
Depth, Boring number 5 Depth, Boring number 6
in in
feet Surface elevation 1010.0 feet Surface elevation 1010.3
J - 1 d -- - - --i-- — 0
3 -
5 -
M
7 -
Topsol ark brown oam
0 - 6"
Brown clay loam
6" - 1'10"
Brown loam
1'10" - 3'8"-MOTTLED 31.8
I i -
2 -
Rusty olive brown 4 -
loam
3'8" - 5'
5 -
End of boring at 5� f•��t.
Standing water
hours after borinq.
Not present in hot-'----x
N ottled so=1:
Observed at 3' 8„ _ iek:t of depth.
Not p_ -send in hn:
Comments:
6 -
7 -
Topsoil dark brown loem
Brown clay loam
8" - 2'
Brown loam
2' - 3'4"-MOTTLED 3'4"
Rusty olive brown
loam
end of boring at 51 Beet.
randinc: wator tah?.::
.aser:t at met of ;iepth,
hours after bc, tnq.
t present in hole X
:: 'ttled soi 1 :
Obsei vc,l at 3' 4" feet of d-:pth.
Comments:
l.tt.1 aQUUt i
PERCOLATION TEST DATA SHEET
12-7-93 8:55 Testing, Inc.
Percolation test readings made b% S—P Teston Starting at p.m.
-
Test hole loc:tti in Lott, Blk . 1, Cof f in site . Hole number 1 . Date hole rrepare.l 12-6-93
Depth of hole htutom t inches. Diameter of hole 6 inches
Soil data from test hole:
Depth. inches Soil texture
0 — 12" Topsoil dark brown loam
Method of scratchine side%all K n i f e
Depth of gravel in hottonr of hole_ 2 inches
Date and hour of initial eater filline 12-6-9 3 &PUR%itial %%atcr filling 12 inches dhow hole Kittont
Method used to maintain at least 12 inches of %cater depth in hole for at least 4 hours_ Automatic siphon
.Maximum %k ater depth above hole bottom during test 6 inche,
Time i I Percolation
.'.me interval. Measurement. I Drop in %rater rate. i Remarks
minutes inches level. inches minutes per
inch I
8:45
prefill !
6
8:55 _
9:25_
4-1/8_
9:30
10:00
3-15/16
10:01
10:31
! 3-1/2
30 min
7.9 "
8.6
Percolation rate = 7.9 minutes per inch.
CERT.#00627
PERCOLATION TEST DATA SHEET
Percolation test readings made by S—P Testing, Inc. 12-7-93 starting at 8:56 P ►�
Lot2,B1k.1,Coffin site 2 12-6-93
Test hole location , Hole number Date hole was prepared
Depth of hole bottom+ 12inches. Diameter of hole 6 inches
Soil data from test hole:
Depth, inches
Soil texture
0 - 12" Topsoil dark brown loam
Method of scratching sidewall Kn i f e
Depth of gravel in bottom of hole 2 inches
Date and hour of initial water fillip 2-6-9 3 2 &PRO f initial eater filling 12 inches abo%e hole tx)uum
Method used to maintain at least 13 inches of water depth in hole for at least 4 hours Automatic siphon
Mammum water depth above hole bottom during test 6 inches
ime
Time
inter\al.
minutes i
Measurement.
inches
i Drop in water
Iesel, inches
Percolation
rate. ; Remarks
minutes per
inch
8 : 4 5
refill
6
8:56
9:26
2-3/8
12.6 30 min
9:29
9:59
_
13.7
10:02
10:32
_2-3/16
2-1/8
14.1
l
P: rcolation rate = 13 . 5 minutes per inch.
.,ru062
PERCOLATION TEST DATA SHEET
Percolation test readings made by S—P Testing, INC . on 12-7-93 starting ar 8.57 a.m
I yIMI
Test hole location Lot 2 , B 1 k .1, Co f f i n site Hole number 3 Date hole a as prepared 12— 6 — 9 3
Depth of hole bottom 12 inchc,. Diameter of hole 6 inches
Soil data from test hole:
Depth. inches Soil texture
0 — 12" Topsoil dark brown loam
Method of scratching sides all Knife
Depth of gravel in bottom of hole 2 inches
12-6-93 2:00pm 12
Date and hour of initial Hater filling . Depth of initial water filling inches above hole bottom
Method used to maintain at least I. inche,- of %%titer depth in hole for at least 1 hours Automatic siphon
. Maminum water depth atx)vc hole bottom during tc.r 6 inches
Time
Percolation
imc
internal.
M j%urement.
Drop in eater
rate.
Remarks
minute,
inches
level. inches
minutes per
inch
8:45
pre f111
6
_
8:57
9:27
---`--^
4-3/8
6.9 30 min
9:28
--
� 9:58
— --- ---
- ---- -- -----4-5/16
--
� 7.0 � »
- -
10:03
j 10:33
4-3/16
j 7.2 "
I
�
Percolation rate _ 7.0 minute, per inch.
CERT.a00627
PERCOLATION TEST DATA SHEET
S—P Testing, INc. a:m.
Percolation test readings made by 9 „„ 10— 2 7-9 Atarting at 8 : 2 5 m.
Testhoklocation Lot2,B1k.1,Coffin site 4�� 10-26-93
Hole number , Date hole was prepared
Depth of hole bottom 12 inches. Diameter of hole 6 inches
Soil data from test hole:
Depth. inches Soil texture
0 — 12" Topsoil dark brown loam
Method of scratching sidewall Knife
Depth of gravel in bottom of hole 2 inches
10-26-93 10:00am 12
Date and hour of initial water fill ine . Depth of initial Hater filling inches above hole N-mom
Method used to maintain at least 12 inches of water depth in hole for at least 4 hours ALtarna t i e a i nhnn
Maximum water depth above hole bottom during test 6 inches
ime
_
Time
interval. Measurement.
minutes i inches
Drop in water
I level. inches
Percolation
rate.
minutes per
inch
Remarks
�•13
6
_t-39
4-1/4
3.
�5 min
�4�
: 04 _ 1L16
3.8
"
9:05
—7
3.9
"
I j
I
-- ---------------------------
-
Percolation rate = 3-7 minutes per inch.
- CEAT'.n00627
PERCOLATION TEST DATA SHEET .
Percolation test readings made b S—P Testing, Inc.10-27-93 8 : 26 m'
g ) o� starting at m.
Lot2,B1k.1,Coffin site 5 10-26-93
Test hole location . Hole number Date hole was prepared
Depth of hole bottom 12 inches. Diameter of hole— 6 ;nches
Soil data from test hole:
Depth. inches Soil texture
0 - 6" Topsoil dark brown loam
6" - 12" Brown clay loam
Method of scratching sidewall
Depth of gravel in bottom of hole 2 inches
Date and hour of initial water filling 10-26-9 3 DIAIt.QQA RLI water filling 12 inches abo%e hole N,ttom
Method used to maintain at least 12 inches of w ater depth in hole for at least 4 hours Antnma t ie siphon
. Maximum water depth abo%c hole bottom during test 6 inches
Time
into intmal. Measurement. Drop in water
minutes inches level. inches
8 • 13 Prefill i _ 6
I
Percolation
rate,
minutes per
inch
Remark%
8:26
8:41
3-7/8
3.9 1 15 min
8:48
9 : 06
9:03 ----
9 : 21
��- --- 3-3/4-----
' 3-5/8 _!
4.0--
4.1 1 "
I
I
Percolation rate = 4.0 minute, I-:r in:h.
CERT.N00627
PERCOLATION TEST DATA SHEET
Percolation test readings made by S—P Testing, INC. ran 10-2 7-9 3 Starting at 8 : 2 7
Test hole location Lot2, B1k.1,Cof f in site , Hole number 6 , Date hole aas prepare j 10-26-93
Depth of hole bottom 12 inches. Diameter of hole 6 inches
Soil data from test hole:
Depth, inches
0 - 8"
8" - 12"
Method of scratching sidewall K n i f e
Soil texture
Topsoil dark brown loam
Brown clay loam
Depth of gravel in bottom of hole 2 inches
10-26-93 10:00am 12
Date and hour of initial water filling . Depth of initial water filling inches above hole bottom
Method used to maintain at least 1' inches of water depth in hole for at least 4 hour. Automatic siphon
. Maximum water depth atxirc hole bottom during test 6 inches
ime
Time
inters al.
minutes
Measurement,
inches
Drop in water
I level, inches
Percolation
rate.
minutes per
inch
I Remarks
8:13
prefill
6
_
8:27
8:42
3-3/8
4.4
15 min
8:47
9:02
IN
3-1/8
4.8
9:07
9:22
OF
3-1/16
4.9
"
_
I
I
Percolation rat. = 4 • .7 _minutes per inch.