HomeMy WebLinkAbout1993-12-16 Septic System Design ReportS -P TESTING, INC,
Steven B. Schirmers — MPCA Cert. No. u[7
951 Katydid Lane NE • St. Michael, MN 55376 * (612) 497-3566
December 16, 1993
Dickey site
Lot 1, Block 1
Orono, Henn. Co., MN ti
This On -Site Sewage Treatment System is Designed for a Type 1, five
bedroom home in accordance with the Minnesota Pollution Control
Agency Chapter 7080 and local ordinances.
The soils on this site are SCS soils mapped - LrB - Lester
loam bordered by - Ha - Hamel loam. A seasonally high water
table was located at 12" to 20", (mottled soil). Due Lo the
seasonally high water table, a Pressurized Mound System will
need to be installed. The bottom of the rock bed must be located
at least 3' above the seasonally high water table.
The soils at a depth of 12" have a percolation rate averaging
8.0 min/inch.
A pumping chamber will need to be installed to lift the effluent
to the treatment area.
The 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 and
pumping chamber in a weather proof enclosure. A warning device must
be installed with a light and sound device, this is in case of a pump
failure. Mercury floats are a good method.
All neighboring wells are located greater than 100' away from the
proposed treatment area.
CONT'D
1
Dickey site
Lot 1, Block 1
Orono
(2)
Keep all heavy equipment off of the proposed treatment area before and
after construction. The treatment area should be marked 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.
Nothing other than gray water, (laundry, showers, etc.) human
waste & toilet tissue should be disposed of into the septic tanks.
Garbage disposals are not recommended. Smaller amounts of laundry
soaps, dish soaps, cleaning agents, etc. are better for the system.
Antibacterial soaps & chlorine agents may kill the bacteria needed
to treat septic effluent properly. Additives are not recommended,
they may 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 �: Schir;ners
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MOUND DESIGN WORKSHEET
(For Flows up to 1200 gpd)
A. FLOW
Estimated 7 gpd (see pages D-7 or I-3, 4, 5)
or measured — gpd x 1.5
B. SEPTIC TANK LIQUID VOLUMES
I - 1) ,J -t 1 -;Doo gallons (seepages C-3 or C-5)
C. SOILS U, r to site evaluation)
1. Depth to restricting layer=
2. Depth of percolation tests = inches
3. Percolation rateg , 0 mpi
4. Land slope 3 %
D. ROCK LAYER DIMENSIONS
1. Multiply flow rate by 0.83 to obtain required area of rock
layer: Daily Flow x 0.83 =
r) S0 gpd x 0.83 sq. ft./gpd = o = sq. ft.-- i
2. Select width of rock layer (10 feet or less) = ft.
3. Length of rock layer = Area + Width =
t -g U sq. ft. + j_ ft. _ (--/ ft.
E. ROCK VOLUME
1. Multiply rock area by rock depth to get cubic feet of rock;
L. sq. ft. x L Q.Sft. _ JLje cu. ft.
2. Divide cu. ft. by 27 cu. ft. /cu. yd. to get cub: z yards;
01_JL cu. ft. + 27 = ';II)_ cu. yd.
3. Multiply cubic yards by 1.4 to get weight of rock in tons;
-j1 cu. yd. x 1.4 ton/ cu. yd. _ -a2� tons.
F. ADSORPTION WIDTH
1. Percolation rate in top 12 inches of soil ismpi
2. Select allowable soil loading rate from table on page E-;
,,4S gpd/fez
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+ .4 S gpd/ft' =_.
Check this value on page E-16.
4. Multiply adsorption width ratio by rock layer width to get
required adsorption width;
Emims" Sewage Flows i. Galkws pa ay
f6pd)
um ixt
.r
Type'
7j'pe 11
7ygw 111
PO
11cxn,
.La
f v
2
300
225
180
3
450
300
218 6t+
4
600
375
236
5
7'0
450
241
6
9l)0
323
M
7
1050
600
77.
t
1200
673
s
Srytit T—h C.p. it:♦
>.n1 -r of
%1,,. -�.m 1..40.1
1..q�J -P- y ...�
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ch.w..:y
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750
1125
Sd4
Inn
ow
4 ter L
151st
2250
7.8 w 9
MIA
llaa7
Rock Bed
h s)orl.
V. 1_i0A`!I
�. If landslope is 2.9 percent or less, basal %vidth includes both the
upslope and downslope dike widths,
2.
Calculate minimum mound size based on geometery:
a. Detern-ine depth of clean sand fill at upslope edge of rock
layer: Separation A . o , feet
b. Multiply rock layer width by landslope to determine drop
in elevation; Slope Difference
l x'_%+100=. -s feet
c. Add depth of clean sand depth of clean sand for llq. W
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;
;.o ft + 1 ft + 1 ft = 1-4.o feet
d. Enter table on page bottom with landslope and upslope
dike ratio. Select dike multiplier of ? .s
e. Multiply dike multiplier by upslope mound height
to get upslope dike width: 3. s -i x i. _ _i �j feet
f. Add the depth of slope difference (2b) to the upslope
height to get the downslope height . c: + -Z ='� feet
g. Enter table on page E-18 with landslope and downslope
dike ru:io. Select dike multiplier of L; .S -i
h. Multiply dike multiplier by downslope mound height
to get downslope dike width: 4. '� x 4.SLl _ _-Li o feet
i. Mininmum mound width is the sum of upslope dike
width plus rock layer width plus downslope dike width;
Iy_ft+eft+ -�v ft= _y feet
j. Subtract the Minimum width G.i from the Absorption
width FA to find the Additional Downslope required for
Absorption
ft- 4J ft = -t,) feet `PSIC
k. Add the Additional Downslope required for Absorptio
to the downslope dike width and recalulate the Total
Mound Width which is is the sum of upslope dike
width plus rock layer width plus downslope dike vvidt;,
-Le ft+j L) ft+ -�-L) ft = L, 4_feet
1. Total mound length is the sum of upslope dike width
plus rock layer length plus upslope dike width;
ft +. (,-Ie ft + �U ft - ��_ feet
a o -+ ('Ct/ -*- a u o
1 bacww
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rw s.p. 1311h,ew
NatNat 16d wwN
Uu..wla�. lvau
�----Total Length 9 L
3:1
4:1
wns upc
5:1
61
7.1
3.1
4.1
U04OPC
5:1
kl
7:1
e.l
v
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0
3.04.0
5.G
70
30
40
5.0
6.0
7.r,
8.0
1
300
1.17
5..'6
6 N
' 41
: ul
3 tl5
4 76
566
6 V
7.11
3 19
3.?5
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6 14
6 W
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7 e
.S
6.64
7
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: ro
3.45
4.17
G 64
546
6.06
5
353
500
6.67
6.57
i 77
I 2 61
313
4. W
4.62
5.19
5.71
6
3.66
5.26
7.14
9.33
1207
2-4
3.23
3 15
4.41
4 93
5.41
7
380
556
7.69
1034
1173
2 4A
3.12
3 %,
4 23
1.70
5.13
e
3.95
5 tl9
9.33
11 S4
1 i 91
2 32
3.23
3.5:
425
4.49
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9
4.11
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9 09
131K
1 y.v2
236
2 94
3.45
3.90
4.30
465
10
429
667
;('D
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_333
231
246
333
375
412
444
I;
4.49
7.14
11.11
1-L5
J:3
2:6
2 7
3.23
361
395
4.26
12
469
7.69
12.5
:1.43
43.75
221
2.70
3.12
3.49
3 bO
449
A. Determine pump capacity:
CGravity 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 = ?ft.
C. "ubtra�t 2 ft. from the rock layer length.
ra 1W _2ft.= sig ft.
d. Determine the number of spaces txtween perforations.
Length perf. spacing= (o(g ft. + --; ft.= spaces
e. .1Z_ spaces + 1 = perforations/lateral
f. Multiply perforations per lateral by number of laterals to
get total number of perforations.
g�e x = y,_ perforations.
g. x'ar gpm.
SELECTED PUMP CAPACITY 3 -1 gpm
B. Determine head requirements:
1. Elevation difference between pump and point of discharge.
Yo feet
2. If pumping to a pressure distribution system, add five feet for pressure
required at manifold
'9feet
3. Friction loss
a. Enter friction loss table with gpm and pipe diameter.
Read friction loss in feet per 100 feet from table.
F.L. _ .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 ipe length =
_ x 1.25 = 1 :� 1 feet
c. Calculate total friction loss by multiplying
friction loss in ft/100 ft by equivalent pipe length.
Total friction loss = 'Z . (o _ x ) ? 1 +100 = Z feet
4. Total head required is the sum of elevation difference,
special head requirements, and total friction loss.
%D +-_+
(1) (2) (30
TOTAL HEAD feet
C. Pump selection
1. A pump must be selected to deliver at least �) gpm (Step A)
with at least I V feet of total head (Step B).
END PERFORATION OF A PERFORATED LATERAL
Gw Cewr
Tgeell "�
• .,
MfarePledift.1 SOW Law
s.r1n«
TABLE OF PERFORATION DISCHARGES IN CPM
Head Perforation diameter (inches)
10
7/r
1/.
Layer N ree,atw FaWk ter few -
Lima" Saw Later _ fwrf++ri`.' cli
0.56
0.74
is
rear 111w oraata Nrlreei
0.90
Isis rater up
0.80
LOW 12' le Edge
o MI
wf ft" Lary
1.17
rerkiel.w;'Laoeloe a1
.. Clew Sawa Lor
fellow, d Lalerel
MfarePledift.1 SOW Law
s.r1n«
TABLE OF PERFORATION DISCHARGES IN CPM
Head Perforation diameter (inches)
10
7/r
1/.
1.0a
0.56
0.74
is
0.69
0.90
2.Ob
0.80
1.04
2s
0.89
1.17
3.0
0.98
1.28
44
1.13
1.47
SA
1.26
1.6S
Wse 1.0 foot of head for residential systems.
bUse 2A het of hssd for other ashbW -wab
Pipe Length
Point of Discharge
Elevation Difference
Pump
F -18b
1.5 inch 2.0 inch 3.0 inch
8Pm F kLkn tns per 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
0.48
SO
3.99
0.58
55
4.76
0.70
60
5.60
0.82
Location or Project Dickey site, Lot 1, Block 1, Orono
Borings made by S -P T,,sting, Inc. Steve Schirmers Date 11-3-93
Classifiction System: AASHO USDA -SCS X Unified Other
Auger used (check two): Hand X or Power Flight or Bucket
Depth, Boring number _1 Depth, Boring number 2
in in
feet Surface elevation 1010.3 feet Surface elevation
- — — ----- — n _ -- -
Topsoil dark brown loam
0 - 10"
Brown clay loam
10" - 1 -1/2' -MOTTLED 1-1 2'
Rusty olive brown
clay loam
2 -
3 -
4 -
5 -
C3
`M
8 -
Topsoil dark brown
loam
0 - 1' -MOTTLED 1'
Rusty olive brown clay
1' - 1-1/2' loam
Rusty olive gray clay loan
1-1/2' - 2-1/2'
Rusty olive gray silty
2-1/2' - 3'4" loam
Rusty olive brown
loam
3 ' 4 " - 51
End of boring at 5' feet.
Standing tater table:
present at 4-1/2' feet of depth,
18-1/2 hours after borinq.
Not present ici ;i•;le
Mottled soil:
Observed at 1
feet of depth.
Not present in hole
Comments:
2 -
3 -
W-=
5 -
6 -
7 -
8 -
1-1/2' - 3'2"
Rusty olive brown
loam
3'2" - 4-1/2'
Rusty olive brown sandy loa
4-1/2' - 5'
End of boring at 5' feet.
Standing water table:
present at feet of depth,
hours after boring.
Not present in hole X
Xottled soil:
Observed at 1-1/2' feet of depth.
Not present in hole
Comments:
Location or Project Dickey site, Lot 1, Block I., Orono
Borings made by S -P :.esting, Inc. Steve Schirmers _ Date 11-3-93
Classifiction System: AASHO USDA -SCS X Unified Other
Auger used (check two): (land X or Power Flight , or Bucket X
Depth, Boring number 3 Depth, Boring number 4
in in
feet Surface elevation 1011.1 feet I Surface elevation 1008.5
Topsoil dark brown loam
0 - 8"
1 _ Brown clay loam
8" - 1'8" -MOTTLED 118"
Rusty olive brown clay loa
2 - 198" - 212"
Rusty olive brown
loam
3 -
2'2" - 3'4"
4
I Rusty olive gray
- loam
5 -
6 -
7 -
8 -
End of boring at _51 feet.
Standing eater =-isle:
present at feet of depth,
hours after boring.
Not present in hole x
Mottled soil:
Observed at 1'8" feet of depth.
Not present in hole
Comments:
u
Topsoil dark brown
loam
n - 1 I _MnTTT.Rn 1
Rusty gray loam
2 -
' - 2-1/2'
3 -
Rusty olive gray
loam
4 -
2-1/2' - 5'
5 -
6 -
FM
8 -
End of boring at 5' feet.
Standing water table:
present at 314" feet of depth,
hours after boring.
present in hole
Mottled soy':
Observed at lfeet of depth.
Not present in hole
Comments:
Location or Project Dickey site, Lot 1, Block 1, Orono
Borings made by S -P ,estinq, Inc. Steve Schirmers Date 11-3-93
Classifiction System: AASHO USDA -SCS X Unified Other
Auger used (check two): Band X or Power Flight or Bucket X
Depth, Boring number 5 Depth, Boring number 6
in in
feet Surface elevation 1009.7 feet Surface elevation 1008.3
0 - --- - --- 0 - --
Topsoil dark brown loam
0 - 10"
1 - Brown clay loam
10" - 1' 8"-MOJTUD
2 Rusty olive brown
clay loam
3 - 108" - 312"
Rusty olive brown
loam
4 -
3'2" - 4-1/2'
Rusty olive brown sandy loa
4-1/2' - 5'
6 -
7 -
End of boring at 5' feet.
Standing eater table:
present at 413" tett of depth,
18-1/2 hours after boring.
Not present in holy
Mottled soil:
Observed at 1'8"feet of depth.
Not present in
Comments:
Topsoil dark brown loam
0 - 10"
1 - Brown clay loam
10" - 114" -MOTTLED 114"
Rusty olive brown clay loam
2 - 1 1 A 19 - 2 1 2 01
Rusty olive brown loam
21211 - 31
3 -
Rusty olive gray
loam
4 -
3' - 5'
5 -
6 -
E�
End of boring at ' _ _ feet
Standing water table:
3'1"
resent at feet of depth,
18-1/2 hours after boring.
Not present in hole
-ofsoil:
Observed at 1'4" feet of depth.
..0t pr( sC-':t ir, hole
Comments:
CL:iti.tr00627
PERCOLATION TEST DATA SHEET
���%
Percolation test readings made b% S—P Testing, Inc. Orr 11-4-93 starting a► 10:14 pmt
Lotl,Blk.l,Dickey site 1
11-3-93
Test hole location , Hole number Date hole ,..,s 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
2
Depth of gravel in bottom of hole inches
11-3-93 k.30pm12
Date and hour of initial water filling pth of initial water filling inches above hole bottom
Method used to maintain at least 12 inches of water depth in hole for at least 4 hours— Automatic siphon
, Maximum water depth above hole bottom during test 6 inches
ime
Time
interval.
minutes
Mcas.trement,
in ches
Drop in water
level. inches
Percolation
rate.
minutes per
inch
Remarks
10:04
preii11
6
10:14
10:44
4-3/4
6.3
30 min
10:55
11:25
4-11/16
6.4
"
11:26
11:56
4-5/8
6.5
I
Percolation rate = 6.4 minutes per inch.
CERT. #k00627
PERCOLATION TEST DATA SHEET
S -P Testing, Inc. 11-4-93 10:15 _-
:,:o!!ion test readings made by on Idwo startim, at p.m.
Test hole location Lotl , Blk . 1 , Dickey site liole number 2 Date hole v as prepared 11-3-9 3
Depth of hole bottom 12 inches, Diameter of hole 6 inches
Soil data from test hole:
Depth, inches
0 - 10"
10" - 12"
Soil texture
Topsil dark brown loam
Brown clay loam
Method of scratching sidewall Kn i f e
2
Depth of gravel in bottom of hole inches
11-3-93 3:30pm 12
Date and hour of initial water filling , Depth of initial water filling inches above hole bottom
Method used to maintain at least 12 inches of water depth in hole for at least 4 hours Automatic siphon _
Maximum water depth above hole bottom during test 6 inches
ime
Time
interval,
minutes
Measurement,
inches
Drop in water
level, inches
Percolation
rate,
minutes per
inch
Remarks
10:04
pref ill
6
10:15
10:45
2-11/16
11.2
30 min
10:54
11:24
t
2-1/2
12.0
"
11:27
11:57
2-7/16
12.3
"
I
}
Percolation rate = 11.8 minutes per inch.
CERT.r00627
PERCOLATION TEST DATA SHEET
S—P Testing, INc. 11-4-93 10:16
Percolation test readings made by on starting at p. m.
Lotl,Blk.l,Dickey site 3 11-3-93
Test hole location Hole number Date hole aas prepare.►
6
Depth of hole bottom 12 inches. Diameter of hole inches
Soil data from test hole:
Depth, inches Soil texture
0 - 8"
8" - 12"
Method of scratching sidewall Knif e
Topsoil dark brown loam
Brown clay loam
Depth of gravel in bottom of hole 2 inches
11-3-93 3:30pm 12
Date and hour of initial water filling , Depth of initial water filling inches above hole bottom
Method used to maintain at least 12 inches of water depth in hole for at least d hours Automatic siphon
6
Maximum water depth above hole bottom during test inches
ime
Time
interval, Measurement.
minutes I inches
I
Drop in "ater
level. inches
Percolation
rate,
minutes per
inch
Remarks
0.04
prefill 6
0.16
10:46
4-1/4
7.1
30 min
:53
11:23
4
7.5
"
11:58
3-7/8
7.8
"
I
Percolation rate = 7.5 nunutes per inch.
CERT.#00627
PERCOLATION TEST DATA SHEET
INc.
Percolation test readings made by S—P Testing, on 11-4-93 start10:17ing at p.m.
Test hole location Lot 1 , B lk . 1 ,Dickey site , I{ole number 4 Date hole was prepared 11-3-93
Depth of hole bottom 12 inches, Diameter of hole 6 inches
Soil data from test hole:
Depth, inches Soil texture
0 - 4"
4" - 12"
Method of scratching sidewalt Kn i f e
Topsoil dark brown loam
Rusty gray loam
Depth of gravel in bottom of hole 2 inches
Date and hour of initial water filling 11— 3 —9 3De;t�tl9 Wal water filling 12—inches above hole bottom
Metnod used to maintain at least 12 inches of water depth in hole for at least 4 hours Automatic siphon
. Maximum water depth above hole bottom during test 6 inches
irne
Time
interval,
minutes
Measurement,
inches
Drop in water
level, inches
Percolation
rate,
minutes per
inch
Remarks
10:04
pretill
6
10:17
10:47
3-1/2
8.6
30 min
10:52
11:22
3-1/4
9.2
"
11:29
11:59
3-1/8
9.6
"
i
Percolation rate = 9.1 minutes per inch.
CERT.#00627 '
PERCOLATION TEST DATA SHEET
Percolation test readings madebY S—P Testing, Inc. on at10:18 a:m_
Test hole location_ Lot1,B1k.1,Dickey site 5 11-3-93
,Hole number , Date hole \\:J,l prepared
Depth of hole bottom 12 inches. Diameter of hole 6 inches
Soil data from test hole:
Depth, inches Soil texture
0 - 10"
10" - 12"
Topsoil dark brown loam
Brown clay loam
Method of scratching sidewall Knif e
2
Depth of gravel in bottom of hole inches
Date and hour of initial water filling 11-3-93 De3p0off i ntial water filling 12 inches above hole bottom
Method used to maintain at least 12 inches of water depth in hole for at least 4 hours Automatic Siphon
6
Maximum water depth above hole bottom during test inches
line
Time
interval.
minutes
Measurement,
inches
Drop in water
level, inches
Percolation
rate, I Remarks
minutes per
inch
10:04
prefill
6
10:18
10:48
4-5/8
6.5 30 min
10:51
11:21
4-7/16 I 6.8 I "
11:30
12:00
4-5/16 7.0
I I
I
------ - --- ------ ------ ----------
I
I i
_
I �
Percolation rate = 6 ' 8 minutes per inch.
CERT.#00627 _
PERCOLATION TEST DATA SHEET
Percolation test readings made by S–P Testing, Inc. -on 11-4-93start ing at -10:19
fa,r„
Test hole location Lot, B k. 1, Dickey siteHole number 6 , Date hole %k as prepared 11-3-93
Depth of hole bot.- 12 inches, Diameter of hole 6 inches
Soil data from tt�.
Depth, inches Soil texture
0 - 10" Topsoil dark brown loam
10" - 12" Brown clay loam
Method of scratching sidewall Knif e
2
Depth of gravel in bottom of hole inches
Date and hour of initial water filling 11– 3 –9 3 , &-pl0Rmitial water filling 12 inches above hole bottom
Method used to maintain at least 12 inches of water depth in hole for at least 4 hours_ Automatic s iphon
, Maximum water depth above hole bottom during test 6 inches
'; ime
Time
interval,
minutes
Measurement,
inches
Drop in wa
level, inches
Percolation
rate,
minutes per
inch
Remarks
10:04
prefill
6
10:19
10:49
"
4-7/8
6.2
30 min
10:50
11:20
4-11/16
6.4
"
11:31
12:01
4-5/8
ti.5
"
Percolation rate = 6.4 minutes per inch.