HomeMy WebLinkAboutRIVER HILLS ESTATES S12582 & S12668Onsite File
River Hills
Estates
#S12582
#S12668
S12668 - Septic Reserved area for former
Lot 2 is eliminated, reserved area for Lot 2A
is same as former Lot 3
ENG IN E E R I NG, LLC PHYSICAL MAILING OFFICE WEB
1300 E. 68th Ave., Suite" 210 P.O. Box 111989 907-344-3114 triadak.com
Anchorage, AK 99518 Anchorage, AK 99511
March 9th, 2021
Municipality of Anchorage
Development Services
4700 Elmore Rd.
Anchorage, Alaska 99507
Attention: Deb Wockenfuss, MOA On -Site
Subject: River Hills Estates Subdivision
Suitability for On -Site Systems
Platting Case 512582
Ms. Wockenfuss,
The following report details the feasibility of the River Hills Estates Subdivision to support on-site water and wastewater
systems for residential single-family homes. The preliminary plat is attached with this report. The site is located in the
Hillside area of Anchorage Alaska, south of Rabbit Creek Road, north of E 156th Ave, with vehicular access from Snow Flake
Drive. See below for a location map.
Location Map
a
r-
5
R_ 4 Ik1'
S o
1 q
3
2 Rov er Su divisio
_ .._...
2 1 - it Est
I Mo ntain
BIk 4 Subd vision
3 Q�a
1
O�
S"e Ffake D, J�
r
,
JAoun ain it Esta es
ddn N
Gudveina Sub vision
<<ttle Rabb
1 2 3 bdiv ston
S,
1
Adn No it ._ -
dCreek
=._ .- _. 4 I f.
_
Subject
- Property
Tract F-1
L 6
4
N
E 1561'' Ave _ C,5s,,A�
Location Map
March 911, 2021
Subject: River Hills Estates Subdivision—SuitabilityforOn-Site Systems
Platting Case 512582
Page 2 of 4
The parcel is approximately 20 acres in size, split -zoned R6 north of Rabbit Creek and R9 to the south. Based on the zoning
and current code, the R6 portion is being subdivided into 6 single-family lots and the R9 portion is to remain an
undeveloped tract.
The site is bordered by Gudveina Subdivision to the west, Rovier Subdivision to the north, Mountain -Air Subdivision to the
east, and E 156`h Ave to the south. The majority of the surrounding lots are developed with residential single-family homes
equipped with on-site water and wastewater systems.
Water Availability
Data from the MOA On-site department indicates the production of existing wells in the area range from 5 to 15 GPM
with an average rate of 8 GPM. The depth of wells ranges from 81 to 139 feet with an average static water level of 40 feet
below ground surface. See below for a table of the well depths and production rates for the wells surrounding the subject
parcel.
Surrounding Well Data
Subdivision
Lot
Well Depth
(ft)
Static Water Level
(BGS)
Production
(GPM)
Gudveina
6
Undeveloped
Gudveina
7
127
42
5.5
Gudveina
1
Unknown
Unknown
Unknown
Rovier, Block 1
2
1
Undeveloped
Rovier, Block 1
3
117
37
5
Rovier, Block 1
4
Unknown
Unknown
Unknown
Rovier, Block 1
5
123
Unknown
10
Rovier, Block 1
6
81
40
6.5
Mountain Air Estates, Block 4
2
116
60
5
Mountain Air Estates, Block 4
3
139
Unknown
15
Mountain Air Estates, Block 7
1
118
38
15
Mountain Air Estates, Block 7
2
100
20
15
Future wells for River Hills Subdivision are anticipated to have similar performance with an average anticipated depth of
120 feet and a production ranging from 5 to 15 GPM. Individual wells are anticipated to be adequate for the subject
property if it is developed as proposed with the preliminary plat configuration.
The development of this subdivision is not anticipated to have any negative affect on the water availability of the
surrounding subdivision or properties.
Soils and Septic System Information
Test holes were excavated on each of the proposed lots. Native sands and gravels with varying silt content were found
throughout the site. A geotechnical report and test hole logs are attached with this report. Percolation testing was
performed for each lot. See below for a table showing the percolation results.
2
March 91", 2021
Subject: River Hills Estates Subdivision—SuitabilityforOn-Site Systems
Platting Case 512582
Page 3 of 4
Perc Testing - September 2020
Lot
Perc Rate (min/inch)
Testing Depth (BGS)
1
<1
5-6 ft
2
4.55 mi
4-5 ft
3
<1
3-4 ft
4
<1
4-5 ft
5
<1
3-4 ft
6
125
4-5 ft
The perc test for Lot 6 was done within a thin silt tense and is not representative of the general subsurface profile across
the site. An additional test hole and perc test on Lot 6 will be completed during the subdivision improvements.
All lots are suitable for on-site wastewater disposal systems. Development of the individual lots will require an engineered
plan for well and septic locations that will be reviewed and approved by MOA On-site to ensure that the septic tanks and
absorption fields are placed outside of the existing and proposed well radii.
Nitrate Analysis
No existing wells within 250 feet of the proposed subdivision have known nitrate levels exceeding 5 mg/I. See below for a
screen capture of nitrate values from the MOA GIS mapper.
Nitrate Values — Screen Capture 3/10/21
3
March 911, 2021
Subject: River Hills Estates Subdivision—SuitabilityforOn-Site Systems
Platting Case 512582
Page 4 of 4
Due to separation distance restrictions from steep slopes, advanced water and wastewater treatment systems will be
required for all lots.
Drainage
The soils within the area are well-suited to infiltrate runoff and the large lot -sizes stipulated by the R6 zoning helps to
ensure that the ratio of impervious area to vegetated area remains low. An engineered grading and drainage plan is being
reviewed by MOA Private Development as part of the Subdivision Agreement process. Drainage generated by this
development is handled on-site and is not anticipated to have any negative affects to neighboring properties.
Conclusion
The subject property and the associated preliminary plat is well-suited for on-site water and wastewater systems. Well
and septic information from the immediate vicinity of the parcel indicate that aquifer production is adequate for single
family homes; the soils are well -draining and will support septic systems.
Thank you for your time and consideration in this matter. If you require additional information, please call 907-720-6128
or email me at grantmathews@triadak.com.
Sincerely,
Triad Engineering, LLC
l
Grant Mathews, P.E.
Attachments
On Site Systems Grading Plan
Geotechnical Report — Northern Geotechnical Engineering
Perc Tests — Northern Geotechnical Engineering
0
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.• 49 TH t .*
GRANT W. MATHEWS
��sTF�• CE 135444 Ap
W`PpROFESS0
April 91", 2021
512582 River Hills Estates
On -Site Comment Response Letter
1. Show the septic area for Rovier Lot 6 to the north.
I have beeii unable to iind reliable information to site the exisnri,g well anid _.eptic on, the
el i i l � �„ ,, ll �. ? r �t � _
£I i`1Cte'if�, C3i)�t� �fJt, i � ic<�!-w ..�.C)�.cil _ �� the 1 1Gu t�C'a[i�i€i Qri ,Cit i] 1Ci ,kt.i E?titur(3k:.C�1 E)VitC.? I%oV3er Lot 6.
2. Per soil log submitted, Lot 6 is not developable. My understanding is that new soils testing will be
completed soon.
'tCit,e1.E:?#?a. �_.�� {1i...t.. �I+� i..�"t., i ,r. ,�ci,3 t:a?i.tlJletf'a �Ji" , ipr?( �. f x(.1',.'_1.. See uti:SC'I`1vG .�? ie.i� cis"a(
3. The designed systems are not within 30' of a testhole.
i.ie s its
Y +;lation rates, are i"? )rtiogeitous across the iie
4. Add slope arrows to the slope(s) created by the proposed road.
5. Add the engineers seal to the calculations.
6. The calculations for the 5 -wide design is incorrect.
Revised.
7. A sand liner is required for the fast, gravelly soil found. Only 6" of sewer rock beneath the
distribution pipe can be used with a sand liner. When redesigning, make sure the trenches are
parallel to the contours. The bottom of the trenches must meet the required vertical separations
to water and impermeable layers. The silt strata found in some testholes may be impermeable.
tt,Evise-_vas itrcorrao;a.L.d i,to the revised Ir,alct,lai?c,;7s (nc, reduction fac•trar £arc=.).
it: icls are . a idle; to the contours. A4.:Cordin,1,, to Northern C_�:-`c-eC:l'nicall c f1 x €1e ring, E`?!J
i111(s �/
i� r r e ,c r i t �;t
a�e�i fiCl Cj�P 3 s,
� r __ �31t fa £Y i�,£,�i, i xz.t=6 i i_U€ t'.., 1�,I�ii "1Si a
£tv.li ✓e. : ?t ve zhe i,)ott,orri of the prolposed Irerich, design
ign
8. The first note shall state "Cat III Advanced Wastewater Treatment Systems"
Prrc)poseci j,iat notes:
Lots u, 2, , +' and 6 skill requireCat III Advanced '.lhistet>ate 3 it citment a��%`�teni i !. tries`
oth tsvise. JI n'.it l d by . e AAOA On ` e `ief, a eflien .
TO ,:kll; bekomp
cmmt tr or 1, _, 3, cvEx ushall he linked u.1 5 NEw`i?o,T;s.
The areas lor drain h ids, X111 i. C?ts _j, 2, 3, and 6 shall not be use'_<:< for ytnuct`,l,:res,
!"E -r
(:zis
t'JUc7y5, or pe3'141E1,, 1E as unless an aItt.ii'i<li?lf-` crpilC stj.: ?iil di-3<ilgli is submitted t to E".Iid
approved by the ( IOA Chi Site EreparkneM,
Design Calculations for Drain Field Sizing for Lots 1, 2, 3, and 6:
Perc Rate (measured) = 1-5 min/inch
Category III Advanced Wastewater Treatment System Application Rate = 6 gpd/sf
Max Bedroom Count = 5
5 x 150 gpd/bdrm = 750 gpd
750 gpd / 6 gpd/sf = 125 sf
5 -wide trench w/ 4 -ft effective depth
1251/5ft=25 ft
*No reduction factor for 5 -wide with sand liner.
25 linear ft trench provided
Grant Mathews, P.E.
0F, A
*:•49a M �
• WANT VI.MATHEWS
9P •• CE 13544401. g,
����®��PROfESS10�aP�,o.� AW
SEPT 2020 SOILS INVESTIGATION
NORTHERN GEOTECHNICAL ENGINEERING
RIVER HILLS ESTATES SUBDIVISION
LOT HDEPTH TO GW PERC RATE
1 NGWE <1 MIN/INCH
2 NGWE 4.55 MIN/INCH
3 7.45' <1 MIN/INCH
4 NGWE <1 MIN/INCH
5 NGWE <1 MIN/INCH
6 9.03' 125 MIN/INCH
NOTE
AN ADDITIONAL TEST HOLE AND PERC TEST WLL BE CDMPIETED
FOR LOT B.
- I\
BRIT GRE J `0 A I 1
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GOOD P00`� P� S6
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i SEE DETAILQA SHEET C5
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—APPROX LIMITS OF
CLEARING & GRUBBING
i I EX BLOC a
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SUBDIVISION AGREEMENT NUMBER 21-002
1. DATA PROVIDED
BY
This will serve to certify
loot hese Recore Drowi'&
ea true and occurole
PreaenteGon or the project
- constructed.
CONTRACTOR:
nnE: _DATE: --
2. DATA TRANSFERRED
BY: _
COMPANY:
RAIL: __ _
1 DATA TRANSFER CHECKED
Boned on peri.Q:. field ob-
wlions by the Engineer
(w on individuol ureer hia/
her direct supervision), the
Conlroclor-provided do to
oppeersto
const—ted.
resent the
Is project Wcled.
BY:
COMPANY:
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c -E. . P T,r
I LOT 6 CONTAINS AN EXISTING
_
I
I
WELL AND SEPTIC SYSTEM.
— _ _ _ _ —(
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I EXACT LOCATION UNKNOWN.
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10' T&E ESMT
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—APPROX LIMITS OF
CLEARING & GRUBBING
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I I
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SUBDIVISION AGREEMENT NUMBER 21-002
1. DATA PROVIDED
BY
This will serve to certify
loot hese Recore Drowi'&
ea true and occurole
PreaenteGon or the project
- constructed.
CONTRACTOR:
nnE: _DATE: --
2. DATA TRANSFERRED
BY: _
COMPANY:
RAIL: __ _
1 DATA TRANSFER CHECKED
Boned on peri.Q:. field ob-
wlions by the Engineer
(w on individuol ureer hia/
her direct supervision), the
Conlroclor-provided do to
oppeersto
const—ted.
resent the
Is project Wcled.
BY:
COMPANY:
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W
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1 °` 1
Municipality of Anchorage
Development Services Department
On -Site Water and Wastewater Section
- 4700 Elmore St.
P.O. Box 196650 Anchorage, AK 99519-6650
www.muni.orq/onsite
(907)343-7904
Performed For:
Legal Description
TP2
Soils Log - Percolation Test
TRIAD ENGINEERING, LLC Date Performed: 9/9/2020
E1/2, SE1/4, SWI/4 Township, Range, Section: T12N, R3W, SEC 35
49
y .. C4 tarGs.6�aiaha[ _ �
i g C9Y 1485$
10-
11-
12-
13-
14-
15-
16-
17-
18-
19-
20 -
BOH @ 12.0 FT
Site Plan
WAS GROUND WATEF
(Feet)
ENCOUNTERED?
ENCOUNTERED
Depth to Water
ORGANIC MAT
1 -
L
Depth to Water After
0
NOT P
Monitoring?
ORGANIC SILT
2-
ON
Date:
3-
68.41"
9/22/20
3
10/30/20
GRAVEL
4-
68.41"
6"
4
9/9/2020
SILT
5-
68.41"
6„
6-
9/9/2020
GRAVEL WITH SILT
<1 MIN.
68.41"
AND SAND WITH
7-
9/9/2020
COBBLES AND
<1 MIN.
68.41"
TRACE BOULDERS
8-
9-
10-
11-
12-
13-
14-
15-
16-
17-
18-
19-
20 -
BOH @ 12.0 FT
Site Plan
WAS GROUND WATEF
NOT
ENCOUNTERED?
ENCOUNTERED
Depth to Water
s
IF YES, AT WHAT DEPTH?
L
Depth to Water After
0
NOT P
Monitoring?
ENCOUNTERED E
2
ON
Date:
9/9/20
68.41"
9/22/20
3
10/30/20
Reading
Date
Gross Time
Net Time
Depth to Water
Net Drop
1
9/9/2020
2 MIN
<1 MIN.
68.41"
6"
2
9/9/2020
3 MIN
<1 MIN.
68.41"
6"
3
9/9/2020
4 MIN
<1 MIN.
68.41"
6"
4
9/9/2020
5 MIN
<1 MIN.
68.41"
6„
5
9/9/2020
6 MIN
<1 MIN.
68.41"
6"
6
9/9/2020
7 MIN
<1 MIN.
68.41"
6"
PERCOLATION RATE <1 (minutes/inch) PERC HOLE DIAMETER 3" PIPE DIAMETER
TEST RUN BETWEEN 5.201 FT AND 5.701 FT
COMMENTS THE INFILTRATION TEST WAS PREFORMED IN GENERAL CONFORMANCE WITH THE FALLING HEAD PERCOLATION
TEST PROCEDURE OUTLINED IN TABLE 3.9 OF THE EPA ON-SITE EATER TREATMENT & DISPOSAL SYSTEMES MANUAL. 12" OF
WATER DRAINED AWAY IN LESS THAN 30 MIN. TWICE SO TEST WAS STARTED.
PERFORMED BY: CLINTON BANZHAF I SEE NOTE ABOVE CERTIFY THAT THIS TEST WAS
PERFORMED IN ACCORDANCE WITH ALLSTATE AND MUNICIPAL GUIDELINES IN EFFECT ON THIS DATE. DATE: 1/11/2021
Municipality of Anchorage
Development Services Department
On -Site Water and Wastewater Section
- 4700 Elmore St.
P.O. Box 196650 Anchorage, AK 99519-6650
www.muni.org/onsite
(907)343-7904
Performed For:
Legal Description:
1-
2-
3-
4-
5-
6-
7-
8-
9-
10-
11-
12-
13-
14-
15-
16-
17-
18-
19-
20-
TP3
Soils Log - Percolation Test
TRIAD ENGINEERING, LLC Date Performed: 9/9/2020
E1/2, SEI/4, SW1/4 Township, Range, Section: T12N, R3W, SEC 35
49
4
OCM,on J. Banzhaf
/
�¢{ f G 14856
�1rl,,ll tsw�
ORGANIC MAT
ORGANIC SILT
GRAVEL WITH SILT
AND SAND WITH
COBBLES AND
TRACE BOULDERS
BOH @ 8.0 FT
FW
WAS GROUND WATER
NOT
Gross Time
ENCOUNTERED?
ENCOUNTERED
Net Drop
1
9/9/2020
s
IF YES, AT WHAT DEPTH?
56.56"
L
Depth to Water After
NOT
O
P
Monitoring?
ENCOUNTERED
E
3
ON
79 MIN
Date:
9/9/20
4.29"
4
9/22/20
89 MIN
10 MIN.
10/30/20
3.62"
Site Plan
Reading
Date
Gross Time
Net Time
Depth to Water
Net Drop
1
9/9/2020
59 MIN
10 MIN.
56.56"
7.24"
2
9/9/2020
69 MIN
10 MIN.
54.14"
4.82"
3
9/9/2020
79 MIN
10 MIN.
53.61"
4.29"
4
9/9/2020
89 MIN
10 MIN.
52.94"
3.62"
5
9/9/2020
99 MIN
10 MIN.
51.73"
2.41"
6
9/9/2020
109 MIN
10 MIN.
1 51.55"
1 2.23"
Ht:KL;ULAI IUN RHI -E v.00 (minutes/inch) PERC HOLE DIAMETER 3" PIPE DIAMETER
TEST RUN BETWEEN 4902 FT AND 5.402 FT
COMMENTS THE INFILTRATION TEST WAS PREFORMED IN GENERAL CONFORMANCE WITH THE FALLING HEAD PERCOLATION
TEST PROCEDURE OUTLINED IN TABLE 3.9 OF THE EPA ON-SITE EATER TREATMENT & DISPOSAL SYSTEMES MANUAL. 12" OF
WATER DRAINED AWAY IN LESS THAN 30 MIN. TWICE SO TEST WAS STARTED.
PERFORMED BY: CLINTON BANZHAF / SHAE MURPHY SEE NOTE ABOVE CERTIFY THAT THIS TEST WAS
PERFORMED IN ACCORDANCE WITH ALL STATE AND MUNICIPAL GUIDELINES IN EFFECT ON THIS DATE. DATE: 1/11/2021
Performed For:
Legal Description
1-
2-
3-
4-
5-
6-
7-
9-
10-
11-
12-
13-
14-
15-
16-
17-
18-
19-
20-
Municipality of Anchorage
Development Services Department
On -Site Water and Wastewater Section
4700 Elmore St.
P.O. Box 196650 Anchorage, AK 99519-6650
www.muni.org/onsite
(907)343-7904
Soils Log - Percolation Test
9.49
►
Cr
ntonJ.Banahaf
TRIAD ENGINEERING, LLC Date Performed: 9/9/2020
E1/2, SE1/4, SW1/4 Township, Range, Section: T12N, R3W, SEC 35
Slooe Site Plan
Depth TP4
(Feet)
ORGANIC MAT
ORGANIC SILT
GRAVEL
SILT
GRAVEL WITH SILT
AND SAND WITH
COBBLES AND
TRACE BOULDERS
BOH @ 8.0 FT
„251 4° 407 W
7 P,B:
rras7rs x¢1'",sat�ao�T
rasa « TP4
}3P2
3 r
rtisa� �s� � -•
F �
r` k ...�
WAS GROUND WATEI YES
ENCOUNTERED?
S
IF YES, AT WHAT DEPTH? 7.532' ON 9/9120 L
Depth to Water After O
P
Monitoring? 7.612' ON 10/30/20 E
DatE 10/30/20
Reading
Date
Gross Time
Net Time
Depth to Water
Net Drop
1
9/9/2020
6 MIN
<1 MIN.
45.37"
6"
2
9/9/2020
8 MIN
<1 MIN.
45.37"
6"
3
9/9/2020
10 MIN
<1 MIN.
45.37"
6"
4
9/9/2020
13 MIN
<1 MIN.
45.37"
6"
5
9/9/2020
16 MIN
<1 MIN.
45.37"
6"
6
9/9/2020
19 MIN
<1 MIN.
45.37"
6"
PERCOLATION RATE <1 (minuteslinch) PERC HOLE DIAMETER 3" PIPE DIAMETER
TEST RUN BETWEEN 3.281 FT AND 3.781 FT
COMMENTS THE INFILTRATION TEST WAS PREFORMED IN GENERAL CONFORMANCE WITH THE FALLING HEAD PERCOLATION
TEST PROCEDURE OUTLINED IN TABLE 3.9 OF THE EPA ON-SITE EATER TREATMENT & DISPOSAL SYSTEMES MANUAL. 12" OF
WATER DRAINED AWAY IN LESS THAN 30 MIN. TWICE SO TEST WAS STARTED.
PERFORMED BY CLINTON BANZHAF/SHAE MURPHY I SEE NOTE ABOVE CERTIFY THAT THIS TEST WAS
PERFORMED IN ACCORDANCE WITH ALL STATE AND MUNICIPAL GUIDELINES IN EFFECT ON THIS DATE. DATE: 1/11/2021
Performed For:
Legal Description:
1-
2-
3-
4-
5-
6-
7-
8-
9-
10-
11-
12-
13-
14-
15-
16-
17-
18-
19-
20 -
Municipality of Anchorage
Development Services Department
On -Site Water and Wastewater Section
4700 Elmore St.
P.O. Box 196650 Anchorage, AK 99519-6650
www.muni.org/onsite
(907)343-7904
Soils Log - Percolation Test
TRIAD ENGINEERING, LLC Date Performed: 9/9/2020
E1/2, SE1/4, SW1/4 Township, Range, Section: T12N, R3W, SEC 35
Aw
4 TH i
. . c- 3, . .
t wiinion.i.B�rt2t:�s
Depth TP5
(Feet)
ORGANIC MAT
ORGANIC SILT
GRAVEL
SILT
GRAVEL WITH SILT
AND SAND WITH
COBBLES AND
TRACE BOULDERS
WAS GROUND WATEI
NOT
Gross Time
ENCOUNTERED?
ENCOUNTERED
Net Drop
BOH @9.5FT
9/9/2020
s
IF YES, AT WHAT DEPTH?
NOT
L
Depth to Water After
ENCOUNTERED O
Monitoring?
ON
9/2/20
p
E
6"
9/9120
9/9/2020
Date:
10/30/20
53.52"
Site Plan
TE_6 1J}r 3d J S?4 i
'^� ;, !,y '-�: '"��R�f~'r • L'1 '"7GA'M.91� `3r.
t 5874&� _ rases o> _ T a¢
"t
.: �
TF4� -.
wt
Reading
Date
Gross Time
Net Time
Depth to Water
Net Drop
1
9/9/2020
2 MIN
<1 MIN.
53.52"
6"
2
9/9/2020
2 MIN
<1 MIN.
53.52"
6"
3
9/9/2020
3 MIN
<1 MIN.
53.52"
6"
4
9/9/2020
3 MIN
<1 MIN.
53.52"
6"
5
9/9/2020
4 MIN
<1 MIN.
53.52"
6"
6
9/9/2020
4 MIN
<1 MIN.
53.52"
6"
PERCOLATION RATE <1 (minutes/inch) PERC HOLE DIAMETER 3" PIPE DIAMETER
TEST RUN BETWEEN 3.960 FT AND 4.460 FT
COMMENTS THE INFILTRATION TEST WAS PREFORMED IN GENERAL CONFORMANCE WITH THE FALLING HEAD PERCOLATION
TEST PROCEDURE OUTLINED IN TABLE 3.9 OF THE EPA ON-SITE EATER TREATMENT & DISPOSAL SYSTEMES MANUAL. 12" OF
WATER DRAINED AWAY IN LESS THAN 30 MIN. TWICE SO TEST WAS STARTED.
PERFORMED BY CLINTON BANZHAF/SHAE MURPHY I SEE NOTE ABOVE CERTIFY THAT THIS TEST WAS
PERFORMED IN ACCORDANCE WITH ALL STATE AND MUNICIPAL GUIDELINES IN EFFECT ON THIS DATE. DATE: 1/11/2021
Performed For:
Legal Description
Municipality of Anchorage
Development Services Department
On -Site Water and Wastewater Section
4700 Elmore St.
P.O. Box 196650 Anchorage, AK 99519-6650
www.muni.or_q/onsite
(907)343-7904
Soils Log - Percolation Test
491H
.* I�
Clinton J. Banzhaf
TRIAD ENGINEERING, LLC Date Performed: 9/9/2020
E1/2, SE1/4, SW1/4 Township, Range, Section: T12N, R3W, SEC 35
Depth TP6
(Feet)
ORGANIC MAT
1-
2- ORGANIC SILT
3-
4-
5-
6-
7-
8-
9-
10-
11-
12-
13-
14-
15-
16-
17-
18-
19-
20 -
SILTY GRAVEL TO
GRAVEL
SILT
SILTY SAND WITH
GRAVEL
BOH @ 8.5 FT
Rita Plan
WAS GROUND WATEI
NOT
Gross Time
ENCOUNTERED?
ENCOUNTERED
Net Drop
1
9/9/2020
S
IF YES, AT WHAT DEPTH?
NOT
L
Depth to Water After
ENCOUNTERED
O
<1 MIN.
ON
P
Monitoring?
9/2/20
E
<1 MIN.
9/9/20
6"
Date:
10/30/20
3 MIN
Reading
Date
Gross Time
Net Time
Depth to Water
Net Drop
1
9/9/2020
2 MIN
<1 MIN.
40.86"
6"
2
9/9/2020
2 MIN
<1 MIN.
40.86"
6"
3
9/9/2020
3 MIN
<1 MIN.
40.86"
6"
4
9/9/2020
3 MIN
<1 MIN.
40.86"
6,
5
9/9/2020
4 MIN
<1 MIN.
40.86"
6"
6
9/9/2020
4 MIN
<1 MIN.
40.86"
6"
F'EKGULA I ]ON RATE <1 (minutes/inch) PERC HOLE DIAMETER 3" PIPE DIAMETER
TEST RUN BETWEEN 2.905 FT AND 3.405 FT
COMMENTS THE INFILTRATION TEST WAS PREFORMED IN GENERAL CONFORMANCE WITH THE FALLING HEAD PERCOLATION
TEST PROCEDURE OUTLINED IN TABLE 3.9 OF THE EPA ON-SITE EATER TREATMENT & DISPOSAL SYSTEMES MANUAL. 12" OF
WATER DRAINED AWAY IN LESS THAN 30 MIN. TWICE SO TEST WAS STARTED.
PERFORMED BY CLINTON BANZHAF/SHAE MURPHY I SEE NOTE ABOVE CERTIFY THAT THIS TEST WAS
PERFORMED IN ACCORDANCE WITH ALLSTATE AND MUNICIPAL GUIDELINES IN EFFECT ON THIS DATE. DATE: 1/11/2021
Performed For:
Legal Description
Municipality of Anchorage
Development Services Department
On -Site Water and Wastewater Section
4700 Elmore St.
P.O. Box 196650 Anchorage, AK 99519-6650
www.muni.or /oq nsite
(907) 343-7904
Soils Log - Percolation Test
TRIAD ENGINEERING, LLC Date Performed: 9/9/2020
E1/2, SE1/4, SW1/4 Township, Range; Section: T12N, R3W, SEC 35
Depth TP7
( Feet)
ORGANIC MAT
1- ORGANIC SILT
2-
4-
5-
6-
7-
8-
9-
10-
11-
12-
13-
14-
15-
16-
17-
18-
19-
20 -
WELL GRADED
GRAVEL WITH SAND
AND COBBLES AND
TRACE BOULDERS
BOH @ 9.1 FT
Site Plan
WAS GROUND WATEI YES
ENCOUNTERED?
s
IF YES, AT WHAT DEPTH? L
Depth to Water After 9.0' ON 912/20 O
9.1' ON 9/9/20 P
Monitoring.
8.6' ON10/30/20 E
Date:
Reading
Date
Gross Time
Net Time
Depth to Water
Net Drop
1
9/10/2020
30 MIN
30 MIN.
0.24"
0.24"
2
9/10/2020
60 MIN
30 MIN.
0.23"
0.23"
3
9/10/2020
90 MIN
30 MIN.
0.24"
0.24"
F'tKGULA I IUN KA I 125.0 (minutes/inch) PERC HOLE DIAMETER 3" PIPE DIAMETER
TEST RUN BETWEEN 4.097 FT AND 4.597 FT
COMMENTS THE INFILTRATION TEST WAS PREFORMED IN GENERAL CONFORMANCE WITH THE FALLING HEAD PERCOLATION
TEST PROCEDURE OUTLINED IN TABLE 3.9 OF THE EPA ON-SITE EATER TREATMENT & DISPOSAL SYSTEMES MANUAL. A 24HR
SOAKING PERIOD WAS COMPLETED.
PERFORMED BY CLINTON BANZHAF/SHAE MURPHY SEE NOTE ABOVE CERTIFY THAT THIS TEST WAS
PERFORMED IN ACCORDANCE WITH ALL STATE AND MUNICIPAL. GUIDELINES IN EFFECT ON THIS DATE. DATE: 1/11/2021
Performed For:
Legal Description:
Municipality of Anchorage
Development Services Department
On -Site Water and Wastewater Section
4700 Elmore St.
P.O. Box 196650 Anchorage, AK 99519-6650
www.muni.org/onsite
(907) 343-7904
Soils Log - Percolation Test
TRIAD ENGINEERING, LLC Date Performed: 4/7/2021
E1/2, SE1/4, SWI/4 Township, Range, Section: T12N, R3W, SEC 35
(ENGINEER'S SEAL)
OF At �Z
� . TH
F 1k
I ''�� GF • i�9�6 ��;� r
TP9
(Feet)
ORGANIC MAT
1 -
ORGANIC SILT
2-
3 -
GRAVEL
4-
BOH @ 4.5 FT
6-
7-
8-
9-
10-
11-
12-
13-
14-
15-
16-
17-
18-
19-
20 -
WAS GROUND WATEF
NOT
ENCOUNTERED?
ENCOUNTERED
Depth to Water
S
IF YES, AT WHAT DEPTH?
L
Depth to Water After
O
NOT p
Monitoring?
ENCOUNTERED E
2
ON
Date:
4/7/2021
Site Plan
Reading
Date
Gross Time
Net Time
Depth to Water
Net Drop
1
4/7/2021
2 MIN
<1 MIN.
6.00"
6"
2
4/7/2021
3 MIN
<1 MIN.
6.00"
6"
3
4/7/2021
4 MIN
<1 MIN.
6.00"
6"
4
4/7/2021
5 MIN
<1 MIN.
6.00"
6"
5
4/7/2021
6 MIN
<1 MIN.
6.00"
6"
6
4/7/2021
7 MIN
<1 MIN.
6.00"
6"
PERCOLATION RATE <1 (minutes/inch) PERC HOLE DIAMETER 6"
TEST RUN BETWEEN 4.000 FT AND 4.500 FT BELOW GROUND SURFACE
INITIAL READING TO DETERMINE IF A SOAKING PERIOD IS REQUIRED WAS TAKEN WITH 6" OF WATER IN PIPE (INITIAL WATER DEPTH IS NOT STATED IN MOA CODE). MOA CODE REQUIRES
MEASUREMENTS IN 10 MIN. INTERVALS FOR 1 HR. IF THE WATER DRAINS IN LESS THAN 30 MIN, THE WATER DRAINED IN LESS THAN 1 MIN. THEREFORE THE PIPE WAS IMMEDIATELY FILLED
AFTER THE 6" OF WATER DRAINED TO PROCEED WITH THE TEST. THE WATER CONTINUED TO DRAIN LESS IN LESS THAN 1 MIN SO 6 MEASUREMENTS/TIMES WERE RECORDED TO PROVIDE A
REPRESENTATIVE PERCOLATION RATE. THESE VARIATIONS TO THE CODE WERE APPROVED VERBALLY AND BY EMAIL BY DEB WOCKENFUSS PRIOR TO THE TEST. THESE WERE THE ONLY
VARIATIONS TO THE MOA TEST PROCEDURE.
PERFORMED BY: SHEA MURPHY I SEE NOTE ABOVE CERTIFY THAT THIS TEST WAS
PERFORMED IN ACCORDANCE WITH ALL STATE AND MUNICIPAL GUIDELINES IN EFFECT ON THIS DATE. DATE: 4/9/2021