HomeMy WebLinkAboutSTUCKAGAIN MANOR Block 1 Lots 3, 4, and 7 Block 2 Lots 3, 6, 9, and 12 Soil Information
4040 "B' Stree! Anchorage, Alaska 99503
Phone (~7)27~,15~t (Telecopier~7)272-5742)
3, 1981
~D13370
1135 W. 8th Avenue
Anchorage, Alaska 99501
Subject:
Subsurface investigation for
sewage disposal, Lots 3, 4,
12 Block 2, Stuckaga n Manor
Dear Mr. Bachner:
OCT 2 1 1981
RECEIVED
suitabi ity of on-site
7 Block t; Lots 3, 6, 9,
Transmitted herein are the so boring logs and percolation
test resu'ts for the test holes placed on the subject ~ots.
Also included are results of laboratory testing on selected
samples, and a ocation sketch for the test holes.
A previous soils investigation was performed for this area by
Alaska Test ab, which consisteo of 9 test holes, 3 of which
had percolation tests run n them. A copy of this report is
attached. This recent'investigation was initiated by a re-
quest from the Municipa'ity of Anchorage Department of Health
and Environmental Proection to supplement the previous inves-
tigation.
Conclusions
The permeability of the site soils appear to be adequate
for on-site sewage disposal. Soil types encountered were
fairly consistent with the previous 'nvestigation.
A hign groundwater table does not appear to be a problem
on the site. Groundwater was encountered only on Lot 12,
Block 2 (T.H. A) and was likely a local perched condition
over the silt layer. However, these test holes were gen-
erally placed in higher ground; any gullies or Iow areas
may have shallow groundwater and should be avoided. Also,
is noted for having intermittent spring activ-
rates
this area
ity; these should also be avoided if encountered.
3. The roi owing table gives the measured percolation
I for' the subject lots.
Melvin R. Ni~ Jmls
BACHNER COMPAN?TM ~-'Septembe~ 3, 1981
Mr Karl Bachner Page 2
Block
1
Lot.
PercolaLion Rate
3 (T.H. C) 5.5 minuLes/inch
4 less than 1.O minutes/:nch
7 (T.H. A) less than 1 g minuges/incn
5 (T.H. B) 2.g minutes/inch
6 3.8 mirutes/inch
9 10.0 minutes/inch
12 (T.N. B) 2.0 minutes/inch
Discussion
The test holes of this exploration were dri led on August 17
and 18, 1981, and were a inches in diameter and about 16 feet
deep. The drilling was done using a Nodwell ~ounted, Mobile
B-50 drill fitted with a hollow stem auger, owned and operated
by Denali Dri I 'ng, Inc. The drilling was supervised and the
test holes were logged by Mr. Terry Barber, geologist with
Alaska Testlab. Grab samples were obtained at about 5-foot
intervals, were visually classified, and were sea'ed in con-
tainers for further testing. Laboratory testing consisted of
grain size dis[r'bution analysis of selected samoles.
The upper sol s at Ehis site are ~argely sands aha gravels with
liLtle si t, and therefore have gooa percolation characteris-
tics. However, some silt avers were encounterea on LOt
Block 1 and LOt 12, Block 2. This silt should be avoiaec, if
possible, in the construction of seepage fields. Systems
placed near Test Hole C of L-3, B-I, and T.H.B., L-12, B-2,
should encounter the more favorable conditions.
The percolation test was performed by filling the test hole
with water and allowing it to soak for 2~ hours. The hole was
then refilled with water, and the drop in the water eve was
monitored for one nour. The percolation rate isted in this
report was computed from the last 10 minutes of the test and
was obtained for a depth of 8 to 1~ feet in the test hole
If you have any questions regarding our investigation, or if
we may be of further service, please feel free to call.
Very truly yours,
DOWL Engineers
Carl A. Bassler
Geotechnical Engineer
Approved by:
Melvin R Nichols, P.E.
Partner
~.'MUNICIPALtTy. OF ANCHoi~AGE
'' ' ' '~ DEPT. OF FIE
L.~ENVIRONME,. ALT/-/ &
,-//'~ OCT 2 '~ 1981
ECEIVED
Test Hole A
Lot 3, Block 1
W.O. ~D13370
Date: 8/17/81
Logged by; TB
.?epth in Feet
From To
0 2.0
2.0 6.0
6.0 10.0
10.0 15.0
Soi Description
Brown Peat, (Pt)
NFS. Grey-Brown Gravelly Sand, ('SP), trace silt,
subrounded gravel, 3/4"% moist, aense
F-2, Brown Gravelly Sand (SP-SM), trace silt, wet by 7'
F-2, Brown Si ty~ Gravelly Sara, (SM), l"+, wet to
sat., dense
MUNICIPALITY OF ANCHORAGE
DEPT, OF HEALTll &
ENVIRONMENTAL PRGTECTION
OCT 2 1 1981
RECEIVED
Bottom of Test Hole:
Frost Line:
Free Water Level:
15.0 ft,
none observed
none observed
Sa.
No. Depth
Type of
Sample Unified
I 5' G SP
2 10~ G SP-SM
3 15~ G SM
Remarks:
1. Type of Sample¢ G:Grab, SPT = Standard Penetration,
U = Undisturbed.
2. Dry Strength, N=None, L=Low, M=Medium, H=High.
3. Group refers to similar material, this study only.
4. Genera Information, see Sheel: 1.
5. Frost and Textural Classification, see Sheet 2.
6. Unified Classification, see Sheet 3.
6A-1
Test Hole B
Lot 3, Block 1
w.O. ~D13370
Date: 8/17/81
Logged by: TB
Depth in Feet
F rom To
Soil Description
0 0.5
0.5 6.0
6.0 10.0
Topsoil
F-4, Brown Sandy Silt, (ML), saturated
F-2, Brown Silty Gravelly Sand (SM); saturated
Bottom of Test Hole:
Frost Line:
Free Water Level:
10.0 ft.
none observed
none observed
Sa. Type of
No. Depth Sample Unified
1 5~ G IVlL
2 10~ G SM
Remarks:
1. Type of Sample, G=Grab, SPT = Standard Penetration,
U = Undisturbed.
2. Dry Stren§th, N=None, L=Low, M=Medium, H=High.
3. Group refers to similar material, this study only.
4. Genera Information, see Sheet 1.
5. Frost and Textural Classification, see Sheet 2.
6. Unified Classification, see Sheet 3.
6A-2
Test Hole C
Lot 3, Block
W.O. ,D13370
DaLe; 8/17/81
Logged by: TB
Depth in Feet
From To
0 0.3
0.3 16.0
Soil Description
Brown Peat, (Pt)
F-l, Brown Silty Sandy Gravel, (GP-GM), 2"+, moist,
dense
Percolation rate : 3.5 minutes/inch
Rate determined for a water level at 10'.
Bottom of Test Hole:
Frost Line:
Free Water Level:
16.0 ft.
none oOserved
none observed
Sa. Type of
No. Depth Sample Unified
I 5' G GP-GM
2 10' G GP-GM
3 15' G GP-GM
Remarks:
1. Type of Sample, G=Grab, SPT = Standard Penetration,
U = Undisturbed.
2. Dry Strength, '~=None, L=Low, M=Medium, H=High.
3. Group refers to similar material, this study only.
4. General In~'ormaLion, see Sheet 1.
5. Frost ano Textural Classification, see Sheet 2.
Unified Classification, see Sheet 3.
GA -3
Lot 4, Block I
W.O. ~D13370
Date: 8/18/81
Logged by: TB
Depth in Feet
From To
Soil Description
0 0.5
0.5 12.0
12.0 16.0
Topsoi
NFS, Grey Gravelly Sand, (SP), Subrounded gravel,
1~"+, moist to wet, dense
NFS, Grey fine-med Sand~ (SP), moist, reed dense
Percolation rate = 1.0 minutes/inch
Water quickly seeped out of hole.
Bottom of Test Hole:
Frost Line:
Free Water Level:
16.0 ft.
none observed
none observed
Sa.
No... Depth
I 5'
2 10I
3 161
Type of
.. Sample.
Unified
G SP
G SP
G SP
Remarks:
1. Type of Sample, G=Grab, SPT = Standard Penetration,
U = Undisturbed.
2. Dry Strength, N=Nbne, L=Low, M=Medium, H=High.
3. Group refers ~o similar material, this study only.
4. General Information, see Sheet 1.
5. Frost and Textural Classification, see Sheet 2.
6. Unified Classif'icaLion, see Sheet 3.
6A-4
Test Hole A
Lot 7, Block 1
W.O. ~D13370
DaLe: 8/17/81
Logged by: TB
Depth in Feet
From To
0 1.0
1.0 7.0 '
7.0 16.0
Soil Descriptior
Topsoil
~IFS/F-2, Brown Gravelly Sand, (SP-SM), trace silt,
moist-wet, mea. dense
NFS, Grey Gravelly Sand, (SW), moist-wet, med. dense
Percolation rate : 1.0 minutes/inch
Water quickly seeped out of hole.
Bottom of Test Hole:
Frost Line:
Free Water Level:
16.0 ft.
none observed
none observed
Sa,
No. Depth
Type of
Sample Unified
5' G SP-SM
10' G SW
16' G SW
Remarks:
I Type of Sample, G=Grab, SPT = Standard Penetration,
U = Undisturbed.
2. Dry Strength, N=None, L=Low, Nl=Medium, H=High.
3. Group refers to similar materia , this study only.
4. General nformation, -see Sheet 1.
Frost and Textural Classification, see Sheet 2.
Unified Classification, see Sheet 3.
6A'5
Test Hole B
Lot 7, Block 1
W.O. ~D13370
Date: 8/17/81
Logged by: TB
Depth in Feet
From To
0 7.0
7.0 8.0
8.0 16.0
Soil Description
F-l/F-2, Brown Silty Gravelly Sand lo Silty Sandy Gravelt
(SM-GM)~ moist to wet,
NFS, Brown fine-med Sand, (SP)
NFS, Brown Sandy Gravel to Gravelly Sand, (GW-SW),
trace silt, 2u+
Bottom of Test Hole:
Frost Line:
Free Water Level:
16.0 ft
none observed
none observed
Sa. Type of
No. Depth Sample Unified
I 5' G SM-GM
2 10' G GW-SW
3 16' G GW-SW
Remarks:
1. Type of Sample, G=Grab, SPT = Standard Penetration,
U = Undisturbed.
2. Dry Strength, N=None, L=Low, M=Medium, H=High.
3. Group refers to similar material, this study only.
4. General Information, see Sheet 1.
5. Frost and Textural Classification, see Sheet 2.
6. Unified Classification, see Sheet 3.
6A-6
Lot 6, Block
W.O. ~D13370
Date: 8/18/81
Logged by: TB
Depth in Feet
From To
Soil Description
0 1.0
1.0 10.5
10.5 16.0
Topsoil
F-l, Brown Silty Sandy Gravel, (GM), Subrounded gravel,
2"+, moist, dense
F2, Brown Silty Gravelly Sand, (SM), Subrounded gravel,
2'~+, moist, dense
Percolation rate = 3.8 minutes/inch
Rate determined for a water level at 14'.
Bottom of Test Hole:
Frost Line:
Free Water Level:
t6.0 ft.
none observed
none observed
MUNICDIPALITY OF ANCH
E" EPT. OF HEALT O£AOE
INVIRoNMENTA~ ~ H &
L r,,~T£CTiON
OCT 2 1981
RECEIVED
Sa. Type of
No. Depth Sample
Unified
1 5' G GM
2 10~ G GM
3 16' G SM
Remarks:
1. Type of Sample, G=Grab, SPT = Standard Penetration,
U = Undisturbed.
2. Dry Strength, N=None, L=Low, M=Medium, H=High.
3. Group refers to similar material, this study only.
4. General In£ormaLion, see Sheet 1.
5. Frost and Textural Classification, see Sheet 2.
6. Unified Classifica[ion, see Sheet 3.
6A-7
Test Hole A
Lot~3~l Block 2
Depth in Feet
From To
W.O. ~D13370
Date: 8/18/81
Logged by: TB
Soil Description
0 1.0
1.0 3.5
3.5 8.0
8.0 14.0
Topsoil
NFS/F~1, Brown Sandy Gravel, (GW-GM), Subnounded
gravel, 2"+
NFS, Brown Gravelly Sand, (SP-SW)
NFS, Brown Sandy Gravel, (GW), Subrounded gravel,
1~", moist, dense
Bottom of Test Hole:
Frost Line:
Free Water Level:
14.0 ft.
none observed
none observed
Sa.
No, Depth
I 5'
2 10~
RemarKs: 1.
3.
4.
5.
6.
Type of
Sample
Unified
G GW
Type of Sample, G=Grab, SPT = Standara Penetration,
U = Undisturbed.
Dry StrengLh, N=None~ L=Low, fYI=Medium, H=High.
Gnoup refers to similar material, this study only.
General In[ormation, see Sheet 1.
FrosL and TexLural ClassifJcaLion, see Sheet 2.
tJnifiecJ Classification, see Sheet 3.
GA-8
Test Hole B
Lot 3, Block 2
W.O. ~D13370
Date: 8/18/81
Logged by: TB
Depth in Feet
From To
0 3.5
3.5 16.0
Soil Description
F-4, Brown organic Silt, (OL), wet, soft
F-l, Brown Silty Sandy Gravel, (GW-GM), Subrounded
gravel, 2"+, moist, dense
Percolation rate = 2.0 minutes/inch
Rate determined for a water level at 8'.
Bottom of Test Hole:
Frost Line:
Free Water Level:
16.0 ft.
none observed
none observed
Sa. Type of
No. Depth Sample
Unified
1 5' G GW-GM
2 10' G GW-GI~
3 161 G GW-GlVi
Remarks:
1. Type of Sample, G=Grab, SPT = Standard Penetration,
U = Undisturbed.
2. Dry Strength, N=None, L=Low, M=Medium, H:High.
3. Group refers to similar material, this study only.
4. General Information, see Sheet 1.
5. Frost and Textural Classification, see Sheet 2.
6. Unified Classification, see Sheet 3.
6A-9
Lot 9, Block 2
W.O. ,D13370
Date: .8/18/81
Logged by: TB
Depth in Feet
From To
Sol Description
0 0.3
0.3 16.0
Topsoil
NFS, Brown Gravelly Sand, (SP-SW), trace silt, Sub-
rounded gravel, 2"+, moist, meo. dense
Gravel increases with oepth
Percolation rate = 10.0 minutes/inch
Rate determined for a water level at 8'.
Bottom of Test Hole:
Frost Line:
Free Water Level:
16.0 ft.
none observed
none observed
Sa. Type of
No. Depth Sample
Unified
I 5' G SP-SW
2 10' G SP-SW
3 16' G SP-SW
Remarks: 1.
3.
4.
5.
6.
Type of Sample, G=Grab~ SPT : Standard Penetration,
U = Undisturbed.
Dry Strength, N=N6ne, L=Low~ M=Medium~ H=High.
Group refers to similar material, this study only.
General Information, see SheeL 1.
Frost and Textural Classification, see Sheet 2.
Unified Classification, see Sheet 3.
6A-10
Test Hole A
Lot 12, Block 2
W.O. ,D13370
Date: 8/18/81
Logged by: TB
Depth in Feet
From To
0 6.5
6.6 11.0
11.0 16.0
Soil Description
F-2, Brown Silty .Sand,
silt, moist-wet, med. dense, 2"+
F-2, Brown SiJty Gravelly Sand,
gravel, 1"+
F-4, Brown Gravelly Sandy Silt,
sat., firm, 1"+
(SM), fine-medium sand, 15-20%
(SM), Subrounded
(Mt), PL+, wet to
Bottom of Test Hole:
Frost Line:
Free Water Level:
16.0 ft.
none ooserved
11.0 ft.
Sa. Type of
No. Depth Sample · Unified
I 5' G SM
2 10' G SM
3 16' G NIL
Remarks:
1. Type of Sample, G=Grab, SPT = Standard Penetration,
U = Undisturbed.
2. Dry Strength, N=None, L=Low, M=Medium, H=High.
3. Group refers to similar material, this study only.
4. General Information, see Sheet 1.
5. Frost and Textural Classification, see Sheet 2.
6. Unified Classification, see Sheet 3.
6A-11
Test Hole B
Lot 12, Block 2
W.O. , D13370
Date: 8/18/81
Logged by: TB
Depth in Feet
From To
0 3.5
3.5 9.5
9.5 14.0
14.0 15.0
15.0 16.0
Soil Description
F-4, Brown SancJy Silt, (ML)
F-l, Brown Silty Sandy Gravel, (GM), Subrounded
gravel, 1"+, moist-wet, dense
NFS, Brown fine-medium Sand, (SW), well graded,
moist, med. dense
F-2, Brown Silty Sand, (SM)
F-l, Brown Silty Sandy Gravel, (GM)
Percolation rate = 2.0 minutes/inch
Rate determined for a water level at 9'.
Bottom of Test Hole:
Frost Line:
Free Water Level:
16.0
none observed
none observed
Sa. Type of
No. Depth Sample Unified
I 5' G GM
2 10' G SW
3 16' G GM
Remarks:
6A-12
1. Type of Samole, G=Grab, SPT = Standard Penetration,
U = Undisturbed.
2. Dry Strength, N=None, L=Low, M=Medium, H=High.
3. Grouo refers to similar material, Lhis study only.
4. General Information, see Sheet 1.
5. Frost and Textural ClassificaLion, see Sheet 2.
6. Unified Classification, see Sheet 3.
~gNIC
o o o o >~ g g § o
RECEIV~.D
8 o°I°'° o ~
L__.P. L A~_ L N_..
_LL~L I I
Test Hole Lolll - Description Guide
The logs often include the following items:
Dcpt In errs[ -- usually shown to 0.1 foot, within that zone no
~xgnit'ica~i change in soil type was observed through drill action, d reft
Frost Classification NFS, Fl, F2, F3, F4, see "Soil Classification
Chart"
Texture .I soil An engineering classification of the soils by particle
LW, NP. M%or ddatency. J
tqae clay-silt groups. Derived from drill action and/or sample data. Very
soft, soft, stiff, very Stiff and hard are commonly used terms.
1-3/8", Shelby tube Y', auger flights (minute-man) 2", Auger flights
(B-50 hollow stem} $"-8'. Larger particles are described ind~ectly by
action of the drilling and are referred to as cobble*, 3" to 8", or
boulders 8'+. Therefore whe. reviewing die gradation sheets, if any,
the description on the hole log must be con,idered for an indication of.
larger particles.
Unified Soil Classification - This is a two letter code. See unified
Classi{~ation sheet ~or further defiuition. In some case~ AASHO and/or
FAA soil classifications may be shown a~ well a~ the unified.
Atterberg Limits useful for fine grained and other plastic softs.
PJ+; natural moisture content believed to be between plastic and liquid
limits
N~; non-plastic, useful as a modifying description of some silty
s~rS~e%i or n,'~rly s;turated soil sample wbeu vibrated or johed - used
Rock flour - finely ground soil that is not plastic but otherwise appears
similar to a c.ayey silt.
Organic Content - usually described as Peat, PT, sometimes includes
discrete particles such as wood, coal. etc. as a modifier to an inorgamc
soil. Quantity described as; trace, or an estimate of volume, or, in case
of all organic, - as Peat. This may include tundra, muskeg and bog
material.
Muck - a modifier used to describe very soft, semi-organic deposits
usually occuring below a peat deposit.
Amorphus peat -- organic particles nearly or fully disintegrated.
Fibrous Peat - organic particles more-or-less intact.
Bottom of Tcsthole - includes last sam pie interval.
Frost Line - seasonal frost depth as described by drilling action and/or
samples at the time of drilling.
Frozen Ground - other than frost line. described by samples, usually
includes description of ice content, often will include moditied Unified
Classification for frozen soils - this is a special case related to
permafrost studies.
Free ~/ater Level - The free water level noted during drilling. This is
not necessarily the static water table at tbe tinge of drilling or at other
seasons; Static water table determination ill other thau very perlneable
soils requires observation wells or piezometer installations, used only in
special cases.
Blow/6' - The number of blows of a 140 weight free falling 30" to.
advance a 2" split spoon 6"; the number of blows for a 12" advance is~
by definition, the standard penetration.
M% - natural moisture content of the soil sample, usually not
pe-~r ormed on clean sands or gravels below the water table.
Type of Sample
S__P, refers to 2" split spoon driven into file soil by 140 pound
weight, a disturbed sample,
S, thin wall tube, "Shelby" used to obtain undisturbed samples
of fine grained soil,
.Ct, "grab" disturbed sample from auger flights or wall of trench,
.~, cut sample, undisturbed sample from wall of trench.
Dry Strength - a useful indicator of a soil's clayey fraction, N'=-None,
L=Low, M=Medium, H=Higb
Group - The samplcsarc placed int. apparently simdar groups based
SOIL
TEXTURAL
CLASSIFICATION
CHART
GRAVEL .30%
CLAY
\
CLAYE
CLAYE'~
OR
SILT
GRAVEL
GRAVELLY SAND GRAVEL
0 I0 20 30 40 50 60 70 80 90
GRAVEL (+ ~4 SCREEN) % BY WEIGHT
I00
FROST CLASSIFICATION SYSTEM
NONFROST SUSCEPTIBLE 501L5 ARE ~NORGANIC SOILS CONTAINING LES5 THAN 3% FINER THAN 0,02 mm,
GROUPS OF FROST-SUSCEPTIBLE SOILS:
F1 GRAVELLY SOILS CONTAINING BETWEEN 3 AND 20% FINER THAN 0.02 mm.
F2 SANDY SOILS CONTAINING BETWEEN 3 AND 15% FINER THAN 0.02 mm.
F3 a. GRAVELLY SOILS CONTAINING MORE THAN 20% FINER THAN 0.02 mm. AND SANDY SOILS
· , (EXCEPT FINE SILTY, SANDS) CONTAINING MORE THAN 15% FINER THAN 0.02 mm.
b. CLAYS WlTI-I PLASTICITY INDEXES OF MORE THAN 1.2. EXCEPT VARVED CLAYS.
F4 a. ALL SILTS INCLUDING SANDY SILTS.
b. FINE SILTY SANDS CONTAINING MORE THAN 15% FINER THAN 0.02 mm.
c. LEAN CLAYS WITN PLASTICITY INDEXES OF LESS THAN 12.
d. VARVED CLAMS.
October 4, 1978
W.O. ~Dl1511
Grid a2043
Mr. Dick Rubio
733 W. 4th Avenue
Anchorage, AK 99501
Subject:
Subsurface Investigation for Suitability
for On-Site Sewage Disposal Systems,
Lots 1-23, Block 5, Stuckagain Manor
Dear Mr. Rubio:
As requested by Mr. Deane Lawrence of DOWL Engineers, we
have performed a subsurface investigasion on the above
referenced property. The data from that investigation is
presented as follows:
Conclusions
Discussion
Test Hole Location Sketch Figure 1
Test Hole Logs Table A
Grain Size Distribution Curves Sheets 1-3
Standard Explanatory Information Sheets 4-6
CONCLUSIONS
The permeability of the site soils on all 23 lots
appears to be adequate, within Municipality of Anchorage
Department of Public Health and Environmental Protection
Regulation, to construct on-site sewage disposal systems.
A high ground water table does not appear to be a
problem on this sise. However, this area is noted for
having intermittent spring activity. Such springs, if
encountered, should be avoided when placing on-site
sewage disposal systems. Also, any shallow gullies or
low, poorly drained areas should be avoided as shallow
ground water ]nay be found in these locations. This
should be addressed when selecting the exact location
for the o~]-s~te sewage disposal systems for each lot
before construction.
The fol]ow~)]g t.3b].e qives a~] estimated percolation
rating fer each lot in the subdivision.
Dick !ubio
Octob~.r 4, 1978
Lot
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
Percolation Ratln~
15.0
15.0 minut~,s
less than 10
less than 5
less than 5
less than 8
less than 8
less than 8
minutes/inch
/inch
0 minutes/inch
0 minutes/inch
0 minutes/inch
0 minutes/inch
0 minutes/inch
0 minutes/inch
2°0 minutes/inch
/2.0 minutes/inch
/}ess than 8.0 minutes/inch
less than 8.0 minutes/inch
less than 8.0 minutes/inch
5.0 minutes/inch
5.0 minutes/inch
less than 5.0 minutes/inch
less than 5.0 minutes/inch
less than 5.0 minutes/inch
less than 2.0 minutes/inch
less than 2.0 minutes/inch
less than 8.0 minutes/inch
less than 10.0 minutes/inch
less than 15.0 minutes/inch
With the exceptions of Lots 1, 2, 9, 10, 14, and 15, the
percolation rating given above was estimated based on extrapola-
tion and interpretation of test hole data and the grain size
distribution curves related back to similar soils in which
percolation tests had been run. We are confident that the
ratings listed are conservative. However, because of the
conservative nature of the ratings, it may prove economic to
actually run percolation tests on Lots ~, 2, 3, 11, 12, 13,
21, 22, and 23 because of the possibility of finding soils
that are substantially better than the ratings estimated.
However, it should be-remembered in all cases, even when a
test hole is placed on every lot, that to extrapolate the
data from s 9" diameter test hole out to a 50'-100' long
absorption trench can present problems. Therefore, on every
lot, even those with a specific percolation test, care
should be taken to ~nspect ~he excavated absorption trench
prior to backfill to verify that there is no substantial
variance from the soil conditions observed in this report.
DISCUSSION
The drillinq was conducted on September 26, 1978 and consist-od
ot: the plaeinq of nine t.e~;t hoists 16'--20' deep. The rest
he, lc:; w, t', drillt,d tt~:ing ;I track mc)nnt~'d, MrM~ilc~ Drill B-50
Mr. Dick Ruble
October 4~ 19?a.
Pdrl b' 3
test holes were logqcd and the drilling supervised by Hr. Jim
Mack, laboratory supervisor with Alaska Tcstlab.
Solid flight, continuous auqcr was utilized. As the drill
bit was raised to the surface, samples were taken directly
off the bit at 5' intervals. Samples were then placed in
sealed plastic bags and transported to the laboratory where
their natural moisture content and dry strength were determined.
Each sample was then visually classified with samples of
similar color, texture and grazn size distribution being
given an arbitrary group designation. Further laboratory
analysis was then performed on composite samples from the
group rather than on individual samples.
A total of slx distinct soil groups were encountered and are
described below:
Group A
is a brown Sandy ~ilt that is highly frost susceptible
being rated F-4. Its unified classification is ML
and its percolation characteristics are poor. It
was a small group and contained only one sample
out of test hole
Group B
is a brown Sandy Silt with a trace of Gravel that
is highly frost susceptible being rated F-4.
Its unified classification zs HL. Its percolation
characteristics are poor though it was a small
sample, the group consisting of only two samples
out of test holes ~1 and ~2.
Group C
was a Gravelly Sandy Silt being highly frost
susceptible being rated F-4. Its unified classifi-
cation is ML and its percolation characteristics
are poor. It consisted of only one sample out of
test hole ~1.
Group D
~roup E
was a brown Silty Sand~ Gravel that is moderately
frost susceptible being rated F-l. Its unified
classification is GM and its gradation is shown on
Sheen 1. Percolation characteristics of this
material are good. This was the predominant soil
found at the site. It was identified in every
hole except ~csn hole ~1.
is a brown Gravelly Sand that is non-frost susceptible
bc'il~q rat'cd.x. .... ,. ].t~]nified classif.icatJon ]s SP
;llld ~ t!l {IF,1 l,/t ioI] 1 ~3 shown Ol1 Sheet 2. Its pcreol a-
Lion characteristics arc cxccllent.
is n 1)ro\.;n incdtum fl:~nd that is non-frost suscc ~l'ib]e
beinq rat~,¢l NI'~i. lt:; qradat.ion is shown en fUn,et 3.
Its m~ifi~,d classii ]cation i~; ~lP and it'~; p~,rcolaticm
Mr. Dick Ruble
Oct.~b~'r 4, 1978
Thou~h the purpose of this exploration was to look specifically
at thc ~)erco]ation characteristics of the site soils with
regard to th ~i.r suJt~bi].ity for construction of on-site
sewage disposal systems, we would like to make a brief
comment the [~ossible use of site soils as subbase material
for road construction. There docs seem to be considerable
moderately to non-frost susceptible soils on the site that
should prove adequate for on-site construction. It may be
necessary though, to do some additional exploration to
further define potential borrow areas.
We hope this report is sufficient to your present needs. If
we may be of further service, please do not hesitane ~o
cc n~act us.
Very sincerely,
ALASKA TESTLAB
Melvin R. Nichols, P.E.
Laboratory Manager
MRN:rb
Enclosures
A
T,'~ b I t. A
we
.,~I)t. 26, 1n
? rola '-PO
0.0' - 1.0'
1 °0' - 8.0'
8.0' 20.0'
O~qaillC
F-4, Si]t, NL, damp, Group A.
F-4, Gravelly Si]t, ~L, wet,
20', Group B and C.
cobbles 12' to
Bottom of Test Hole:
Frost Line:
Free Water Level:
20.0' Remarks:
None Observed
None Observed
Per,: Test
!5 minute/inch
Sample Depth
5.0'
2 10.0'
3 17.0'
Type of Dry
Blows/6" M% Sample Strenqth Group UnJ (Sod
- 14.7 G L A
- 17.6 G L B
- I 1 . 7 G L-.~ C ,.'4L
Remarks: 1.
3.
4.
5.
6.
Type of Sample, G=Grab, SP Standar'd Penetration,
U = Undisturbed.
Dry Strength, N=None, L=Low, M=Ncdium, H=High.
Group refers to simJ]ar material, this study only.
Geueral ]nformatiou, see Sheet 1.
Frost and Textural Classification, see Sheet 2.
Unified C].assJfJcatJon, soo Sheet 3.
Tcu;L llol c'
¥40 ",D1 )ql 1
Date': S(,[)L. 26,
0.0' - 5.0'
5.0' - 10.0'
Soil D(,scr tpt ion
Pc,at, wet, soft.
I"-4, Silt, HL, wet.
Bottom of Test llole: 10.0' Remarks:
Frost Line: None Observed
Free Water Level: None Observed
Bole
gully
located
in a
small
T,r~q,l~,d ~.,: J .
SoJ ! D(,SC~ll)tlOll
0.0' 1.0'
1.0' 7.0'
7.0' 12.0'
Orga'lJc overburden.
F-l, brown Silty Sandv~ Gravel, (]~, damp,
Group D.
F-4, brown Sandy Silt, ML, damp to 10',
wet, Group ~.
5hen
12.0' 20.0'
F-4, brown Gravelly Silt, ML, wet.
Bottom of Test Hole:
20.0' Remarks: Some water (6") snandinq
on silt layer 7', t~erched.
Frost Line:
Free Water Level:
None Observed
None Observed
Sample Depth
5.0'
2 8,0
Blows/6"
Type of Dry
Sample S_trenqth Grouo U_n_~ fj e_d_
G N D
G L B
I. Type of Sample, G=Grab, SP = Standard Penetration,
U undisturbed ·
2. Dry Strenqtb, N=None, L--Low, M=Medium, ll-:IlJqh.
3. Group re/'~rs to szmilar material, this study only.
4. General ]uforn]ation, see Sheet 1.
5. Fros~ aud Textural Classification, see Shoo5 2.
6. Un~[i,'d C]assiJ'icau/ou, see Shceu 3.
Table' A
we ItDI t',1 ]
D,LLc: fk,i)k...'~r~, 1~
[){,Ill h itl l'~'~'l.
0.0' ].0'
3.0' 12.0'
12.0' 14.0'
14.0' ~6.0'
Soil [),,serJl)t.lon
F-1,/F-2, brov.'n Silty Sandy qraw~l, GM,
,_q_j~] t___v_ Gravel iv' ,ah'{n~I ,- ...... ' ........ -"' ,
S!l, wet to ~ damp to
3'
NFS, grey Sand, SP, layered with a Sandy
Gravel, GP, danlp, Group E.
F-l, brown ~ilty Sandy Gravel, GM, damp,
Group D.
F-2, brown Gravelly Silty Sandy, SM, wet.
Bottom of Test Hole:
Frost L~ne:
Free Water Level.:
16.0'
None Observed
None Observed
Sample Depth
5.0'
2 8.0'
3 13.0'
Type of Dry
Blo;,:s/6" M% Sample Strength_ GrouP_
a.3 G N E
4.2 G N E
5.9 G N D
Unf fi. ed
SP
SP
G..'!
Remarks: 1.
3.
4.
5.
6.
Type of Sample, G=Grab, SP Standard Peneurat~on,
U := undintnrbod.
Dry Siren<lib, N=None, L=Low, ?~::bledium, II=HJq}l.
Group ret. ers to szmzlar material, ti:ts study on],'.
(;oncr~] TI]~OFIIWIIiJOII, SOO SI'leek I .
Frost a~d Textural C]assificat].on, sce Sheet'. 2.
UnifJod ClassilTiCnLJOn, see Si]ccc 3.
Table A
Dt ~Lh in 1',.. t.
0.0' 12.0'
Soil D(,scrlption
t'-1, brown Silty Sdn. l¥ Crnvel, GM, cobbles
7' to 12', ~roup ~.
Bottom of Test Bole:
Frost Line:
Free Water Level:
12.0' Remarks:
None Observed
None Observed
Perc. nest 5.0 rain/inch
Sample Depth
1 5.0'
Type of Dry
Blows/6" ~!% ~ample Strength Group Unified
6.1 G
N D
Remarks:
2.
3.
4.
5.
6.
Type of Sample, G=Grab, SP = Standard
U = Undisturbed.
Dry Strength, N=None, L=Low, M=Medium,
Group refers to similar material, this
General Infcrmation, see Sheet 1.
Frost and Textural Classification, see
Unified Classification, see SI~eet 3.
Penetration,
H=High.
study onl. 5'.
Sheet 2.
! d b 1 . A
0.0' 1.5'
1.5' ?.0'
7.0' 16.0'
Soil D,,scrl')~ ~en
Organic ovcnfburden.
NfS, brown Sandy Gravel, GP/GM,
F-l, brown Silt,, Sandy Gravel,
10'-16', Group D.
damp.
GM, cobbles
Bottom of Test Ilole:
Frost Line:
Free Water Level:
16.0'
None Observed
None Observed
Salnp].e Depth
1 5.0'
2 10.0'
Type of Dry
Blows/6" H% Sample _Strenoth~ GrouP_
6.4 G N
11.1 G N D
Unifi.,.~
Gl'
Remarks: 1.
3.
4.
5.
6.
Type of Sample, G=Grab, SP Standard Penetration,
U = Undi-~;tur bed -
Dry Strength, N=None, L=Low, M=Medium, It=llJ~h.
Group re£ers to s~milar material, this study only.
G~ncra] Information, see Sheet 1 .
['rosn and Texuural Classifica%:zon, soo Sheet 2.
Unified Classification, see Sheet 3.
T;Ibl t' A
LO(Tq('d BV: J. r.~ack
Date: S,,pt. 26, 197.q
0.0' 0.5'
0.5' 4.0'
4,0' 16.0'
Bottom of Test Hole:
Frost Line:
Free Water Level:
Soil Description
Organic overburden.
NFS, brown Sandy Gravel, GP, damp.
F-l, brown ~ilty Sandy Gravel,
Group D.
16.0' Remarks:
None Observed
None Observed
Perc.
damp,
tes~ 2.0~in/inch
~ample D~E&~
1 5.0'
2 10.0'
Type of Drv
" ho Sample Strength Grouo Unified
Blows/6 '~ ........
3.7 G N D
3.3 G N D G;.[
Remarks: 1.
Type of Sample, G=Grab, SP = Standard Penetration,
U undisturbed.
Dry Strength, N=None, L=I.ow, H=Medium, II=High.
Group roi-ers to similar material, chis study only.
Genera] Informarion, see Sheet I.
F~-ost and Tex[:ura] Classification, see Sheet 2.
Unified Classification, see Sheer. 3.
'1 c:;I lie ] ~'
Tdl,l c A
t',oocfud Bv:
Date:
J. tla c k
26, 1 [!/~I
0.0' 1 .0'
1.0' - 16.0'
Soil Dcscr~)tion
Oruan~c overburden,
F-l, brown Silt. v Sandv Gravel,
very dense [~elow ]-2.--0'-r, Group D.
do r~p,
Bottom of Test Hcle:
Frost Line:
Free Water Level:
16.0'
None Observed
None Observed
~ample Depth
1 5.0'
2 10.0'
Type of Dry
Blows/6'~ M% Sample Strenqth Group Unified
5.4 G N D GM
5.5 G N D GM
Remarks: I .
3.
4.
5.
6.
Type of Sample, G=Grab, SP Standard Penetration,
U = Undisthrbed.
Dry Strenoth, N=None, L=Low, M=Medi.um, H=tii~h.
Group refers to similar'material, this study only.
General Information, see Sheet
Frost and Textural Classification, see Sheet 2.
Unified Classification, see Sheet 3.
q_',lb] e A
WO riD1'5!1
l,om~(,(.I 1;7: J. Mm'l:
Ddt(': ,%-'~,Dt-. 2~, 1~'i~!
0.0' 0.5'
0.5' 4.0'
4.0' 6.0'
6.0' 12.0'
12.0' 16.0'
Soil Dc, scrit~t ion
Organic overburden.
F-l, brown ~ilty Sandy Gravel, GH, damp,
Group D.
NFS, brown Sand, SP, damp, Group F.
NFS, brown Gravelly Sand, SP/SW) damp,
Group E.
F-l, brown ~il~y Sandy Gravel, GM, damp,
Group D.
Bottom of Test Itole: 16.0'
Frost Line: None Observed
Free Water Level: None Observed
Type of Dry
Sample Depth Blows/6" M% Sample Strength Group Unified
I 5.0' 3.6 G lq F SP
2 10.0' 3.0 G N E SP
3 I 5.0 ' 3.3 G N D G."d
Remarks: 1. Type of Sample, G=Grab, SP = Standard Penetration,
U Undisrut-bcd.
2. Dry Strcn(~kh, N:-Hone, L=Low, M=Medium, H=l!igh.
3. Grou[~ rotors to s].mi].ar material, this study on]v.
4 . (]~'IICI'/]i [FfOl'lllatlOll, SOC ~;beo~ I .
5. I-'rot;t and 'ik'xruva] C/assifncation, see Sheet 2.
6. 'U~l'it,d Cla~:;i(icat:~en, s(,o Shecu 3.