HomeMy WebLinkAboutGREGORY Soils Logs S-3780
4040 "B" S'~PEE:T,
ANCHORAGE, At. ASKA 99503
PHONE: 907-279-2581
Walatka & Assoc.
3107 W. 29th Ave.
Anchorage, AK 99503
Attn:
Mr. Fred Walatka
July 3]., ]_975
W.O. #17387
Subject: Addendum to the Soils Investigation
of Gregory Subdivision
Gentlemen:
At your request, we have reviewed our report of 0uly 7, 1975.
Sam Sparkman, the technician who logged 'the ~estbo]es, des-
cfi_bed the soils above the free water level as b~i~ wet.:
This is not uncommon and we do not expect that ali. the voids
in this material are filled with wate~ We therefore fee]
~/~ free water leve3 is relate, vel sh
..... " ' Y - ' -thi~ area. A
leach field J_s therefore reco~uended. The construction of
the leach field should conform to that o~ a standard septic
system~with regard to ~bsorption area; however the depth of
~nbedment should be bevween three and ~our feet to reduce
~-'~the possibility of freezinq the pipes. A tt~aw wire extend-.
lng from the outlet of the system through one of 'the legs of
the leach field is a prudent precaution in th:i_s regard.
It is also prudent 'ho design 'hbo system so that a substantial
gravity head exists between the ].each field and tine treatment
system.
We trust the foregoing transmittal is sufficient to your
immediately needs. Please feel free to call should que. stions
arise in this regard, or if we can be of further service to
this project as it develops.
Very truly yours,
ALASKA TES'J?LAB
JML: chc ..~ /' ~' ,
Ill .[ )/; / / Jonn M. Lambe
Natty l~./];,ee,
4040 "B" STREET,
ANCHORAGE, ALASKA 99503
PHONE: 907-279-2581
July 7, 1975
WO #17387
Walatka & Associates
3107 West 29th Avenue
Anchorage, Alaska 99503
Attention: Mr. Fred Walatka
Subject: Soils Investigation
Gregory Subdivision
Dear Fred:
Transmitted in this letter are the results of the subsurface
soils investigation performed on the subject property on July
2, 1975.
Drilling was accomplished with a Nodwell mounted Mobile B-50
drill fitted with a 6" solid flight auger.
Grab samples were taken at five-foot intervals by pulling the
auger out of the hole and removing the samples from the flights
from near the bit. As the samples were recovered, they were
visually classified and each was pleced in a plastic bag and
transported to the laboratory.
The samples were visually classified and grouped according
to similarities in texture and particle size, and given an
arbitary group letter designation to reference the soil types
between test holes.
The compilation of the field and laboratory data is recorded
on the test hole logs which follow immediately after this letter.
Following the test hole logs are three sheets with data explaining
the soils classification systems employed and other information
regarding the test hole logs.
Basically the soils system in the study area can be described
as a three layer system. Uppermost is eight inches to one
foot of organic overburden which is immediately underlain by
NFS gravelly sand to sandy gravel to a depth of 7 to 14 feet.
Underlying these clean materials is an F-4 silt or sandy silt.
In all five test holes the free water table was encountered
at between 7-1/2 to 9 feet below the existing ground surface.
Walatka & Associates
July 7, 1975
Page 2
In reviewing the logs, please note that the unified classification
of each of the major soil stratum follows at the end of the
-verbal description of each layer, and is again noted at the
bottom of each test hole log under "unified classification"
in the sample description.
We trust the foregoing data transmittal is sufficient 'to your
immediate needs. Please feel free to call the writer should
questions arise in this regard~or if we can be of further service
to this project as it develops.
Very truly yours,
ALASKA TESTLAB
John M. Lambe
JML:mm
Enclosure
Approved: H~~~,
H~ry R.~et'~PE
Fred Walatka
July 3, 1975
Test Hole No. 1
TABLE A
W.O. #17887
Depth in Feet
From To
0 1.0
1 .0 7.0
7.0 16.0
Ottom of Test Hole:
Frost Line:
Free Water Level:
SOIL DESCRIPTION
Organic Overburden.
NFS~ brown Gravell_~ Sand, wet, SP
F-4, tan Sand~ Silt becoming grey Silt by 15 ft.
saturated, ML --
16.0 ft.
None observed
8.0 ft.
SA.
NO. ?~pth
1 5-6
2 9-10
3 15-16
Type of
Blows/6" M%
..... Grab
..... Grab
Grab
Dry
S h r e n.~.3, th Groin. Unified
--- A SP
--- B ML
--- C ML
Notes:
1) Group: Refers to similar samples this study only.
2) Type of Sample: G-= Grab; SP = Standard Penetration.
3) Unified Classified, see Sheet 2.
4) Frost and textural classification, see Sheet 1.
5) General information, see Sheet 3.
Fred Walatka
July 3, 1975
Test Hole No. 2
Depth in Feet
· From To
0 1.0
1 .0 11 .0'
11.0 16.0
TABLE A '
SOIL DESCRIPTION
W.O. #17887
Organic Overburden.
NFS, brown Sand~ Gravel becoming Gravelly SanQ
by 9 feet, wet (saturated @ 8.5 ft.), GP/SP
F-4, grey Silt, NP, ML
Bottom of Test Hole:
Frost Line:
Free W~ter Level:
16.0 ft.
None Observed
8.5 ft.
SA.
N~O. Depth
1 5-6
2 9-10
3 15-16
Type of Dry
Blows/6" M% ~.~mple_ Strength Grou~ Unified
.... .- Grab --- D SP
..... Grab --- A ~L
..... Grab --- E ML
Notes:
1) Group: Refers to similar samples this study only.
2) Type of Sample: G = Grab; SP = Standard Penetration.
3) Unified Classified, see Sheet 2.
4) Frost and textural classification, see Sheet 1.
5) General information, see Sheet 3.
Fred Walatka
July 3, 1975
Test Hole No. 3
TABLE A
W.O. #17887
Depth in Feet
From To
0 0.6,
0.6 13.0
13.0 16.0
SOIL DESCRIPTION
Organic Overburden
NFS, brown Gravell~ Sand wet (saturated @ 9.0 ft.),
SP
F-4, grey ~oarse Silt, saturated, NP, ML
Bottom of Test Hole:
Frost Line:
Free Water Level:
16.0 ft.
None observed
9.0 ft.
SA.
NO. Depth
1 5-6
2 9-10
3 15-16
Type of Dry
Blows/6" M% Sam~e___ Strength Group Unified
..... Grab --- A SP
..... Grab --- A SP
..... Grab --- F ML
Notes:
1) Group: Refers to similar samples this study only.
2) Type of Sample: G = Grab; SP = Standard Penetration.
3) Unified Classification, see Sheet 2
4) Frost and textural classification, see Sheet 1.
5) General information, see Sheet 3.
]Fred Walatka
July 3, 1975
Test Hole No. 4
Depth in Feet
From To
0 0.6
0.6 14.0.
14.0 16.0
TABLE A
SOIL DESCRIPTION
W.O. #17887
Organic Overburden
NFS, brown Sand~ Gravel becoming Gravelly Sand
by 9 feet,' Qet (~ted @ 8.0 ~-~.j TsP
NFS/F-2, brown Sand, saturated, SP/SM
Bottom of Test Hole:
Frost Line:
Free Water ]bevel:
16.0 ft.
None observed
8.0 ft.
SA. Type of Dry
N_20. ~epth B__l~ws/6" M% Samp~e~ StreDgth Group Unified
1 5-6 ..... Grab --- D GP
2 9v10 ...... Grab --- A SP
3 15-16 ...... Grab --- G SP/SM
Notes:
1) Group: Refers to similar samples this study only.
2) Type of Sample; G = Grab; SP = Standard Penetration.
3) Unified classification, see Sheet 2.
4) Frost and textural classifJ, cation, see Sheet 1.
5) General information, see Sheet 3.
Fred Walatka
July 3, 1975
Test Hole No. 5
TABLE A
W.O. #17887
Depth in Feet
From To
0 1.0
1 .0 7.0
7.0 16.0
SOIL DESCRIPTION
Organic Overburden
NFS, brown ~ravel~ Sand, wet, SP
F-4, grey Silt, saturated, NP, ML
Bottom of Test Hole:
Frost Line:
Free Water Level:
16.0 ft.
None 6bserved
7.5 ft.
SA.
N__qO. ,,Depth
'1 5- 6
2 9-10
3 15-16
Blows/6"
Type of Dry
~ Sample-- Stre~ t~ Grou~ Unified
-- Grab --- A SP
-- Grab --- F ML
-- Grab --- F ML
Notes:
1) Group: Refers to similar samples this study only.
2) Type of Sample: G = Grab; SP = Standard Penetration.
3) UnifJ. ed ClassifJ. cation, see Sheet 2
4) Frost and textural classification, see Sheet 1.
5) General Information, see Sheet 3.
SOIL CLASSIFICAT[ON CHART
30% GRAVEL
CLAY
CLAYEY
OR
SILTY
SAND
CLAYEY CLAYEY
SILTY SILTY
GRAVELLY SAND SANDY
CLAYEY
GRAVE[_
SILTY
GRAVEL
SAND GRAVELLY SAND SANDY GRAVEL GRAVEL
0 10. 20 30 40 50 60 70 80 90 100
GRAVEL (+#4 SCREEN) % BY WEIGHT
NONFROST SUSCEPTIBLE SOILS ARE INORGANIC SOILS CONTAINING LESS 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% FINlZR THAN 0.02 mm.
F3 a. GRAVELLY SOILS CONTAINING MORE THAN 20% FINER TI-JAN 0.02 mm. AND SANDY SOILS
(EXCEPT FINE SILTY, SANDS) CONTAINING MC)RE THAN 15% FINER THAN 0.02 mm.
b, CLAYS WITH PLASTICITY INDEXES OF MORE THAN 12, EXCEPT VARVED CLAYS.
F4 a, ALL SILTS INCLUDING SANDY SILTS.
b. FINE SILTY SANDS CONTAINING MORE THAN ]5% FINER THAN 0.02 mm.
c, LEAN CLAYS WITH PLASTICITY INDEXES OF LESS THAN 12,
d, VARVED CLAYS.
Test Hole Log - Description Guide
Thc soil descripSions shuwi,, on the Jogs are the best estintatc or the soil's
characteristics at the time of field examination and as such do not achieve thc
precision of a laboratory testing procedure. If the log includes soils samples,
those samples receive an independent textural classification in tbc laboratory
to verify the field examination,
The lugs often include thc following items:
Depth Interval - usually sho~vn to 0.1 foot, witbin that zone no
significant change in soil type was observed through drill action, direct
observation or sampling.
Frost Classification -- NFS, Fl, F2, F3, F4, see "Soil Classification
Chart"
Texture of Soil - An engineering classification of the soils by particle
size and proportion, see "Soil Classification Chart", note the
proportions are approximate and modifications to the soil group due to
stratification, inclusions and changes in properties are included.
Moisture Content - this is a qualitative measure:
dry, no or little apparent surface moisture,
damp, ntoisture forms portion of color, less than plastic limit,
wet, no free water, often soft, if cohesive soil,
saturated, frcc water may be squeezed out, ifa free draining soil;
di]atent at natural moisture content, ifa non plastic silt or fine
sand. (Tb~ moisture content is further definedby reference to PI,
LW, NP, M% or dilatency.}
_Detlsity -- refers to more-or-less non-cohesive soi]s~ such as sand gravel
mixtures with or without a fine fraction, derived froln drilling action
and/or sample data: usually described as: very loose, loose, medium
dense, very dense. General intent is to portray earthwork
characteristics.
Stiffness - refers to more-or-less cohesive soils and fine grained silts of
the clay-silt groups. Derived from drill action and/or sample data. Very
soft, soft, stiff, very stiff and hard are commonly used terms.
Particle size - Tbe largest particle recovered by the split spoon is
1-3/8", Shelby tube 3", auger flights (minute-man) 2", Auger flights
(B-50 hollow stem) 6'-8". Larger particles are described indirectly by
action of tbe drilling and are referred to as cobbles, Y' to 8", or
boulders 8"+. Therefore when reviewing the gradation sheets, if any,
the description on the bole log must be considered for an indication of
larger particles.
Unified Soil Classification This is a two letter code. See Unified
Clnssification sheet for further definitiom In some cases AASHO and/or
[:AA soil classifications may be sbown as well as tbe unified.
Atterberg Limits useful for fine grained and other plastic soils.
P~l; natural moisture content believed to be less than plastic limit
PI+; Imtural moisture content believed to be between plastic and liquid
I~mit s
Lw+; natural nloisture content believed to be greater than liquid limit
N~P; non-plastic, useful as a modifying description of some silty
materials.
l)iJatency_ -- is tile ability of water to trlig~ate to tile surface of a
sittut,dcd or nearly saturated soil sample ;vbcn vibrated or jolted -. used
as an aid to determine it'a fine grained soil is a slightly or nrta-plastic
silt or a volcanic aslt,
Rock flour - finely ground soil that is not plastic but otbcrwise appears
~ar to a clayey silt.
Organic Content - usually described as }'eat, PT, sometimes includes
discrete particles sucb as wood, coal, etc. as a modifier to an inorganic
soil. Quantity described as: trace, or an estbnate of volume, or, in case
of all organic, ~ as Peat. This may include tundra, muskeg and bog
material.
Muck -- a inodifier used to describe very soft. semi-organic deposits
usually occuring below a peat deposit.
Amorphus peat - organic particles nearly or fully disintegra ed.
Fibrous Peat - organic particles more-or-less intact.
Bottom of Testho]e - includes last sample interval.
Frost Line - seasonal frost depth as described by drilling action and'or
~qmples at the time of drilling.
Frozen Ground - other than frost line. described by samples, usually
includes description of ice content, often will includ~ modified Unified
Classification for frozen soils ~ tbis is a special case related to
permafrost studies.
Free Wnter Level --Tbe free water level noted during drilling. This is
not necessarily thc static water table at the time of drilling or at other
seasons. Static water table detcrlllinatJon in other than very permeable
soils requires observation wells or plezometcr installations, used only'in
special cases.
Blowl6" - The number of blows of a 140 weight free falhng 30" to
advance a 2" split spoon 6"; the number of bluws for a 12" advance is,
by definition, the standard penetration.
,~t]~ _ natural moistme content of the soil sample, usually not
performed on dean sands or gravels below the water table.
]'ype ofSampl~ -
S}~, refers to 2" split spoon driven into the soil by 140 pound
weight, a disturbed sample,
~, thin wall tube. "Shelby" used to obtain und~stmbed samples
of fine grained soil,
~, "grab" disturbed sample from auger Nights or wall of trench,
~, cut samplt., undisturbed sample from wall of trench.
l)t~y Strength - a useful indicator of a soil's clayey fraction, N=None,
I.= ow, M=Medium, II=}ligb
Gro~ - The samples are placed into apl) we y s ar groups ba~cd
on color illld texture alld are rrb trariJy assigned a group ]ctter. Further
Paul C~rr
DEQ Comments
Pap;e Two
July 24, 1975
29.
30,
31.
32.
34,
35.
d!sposp,1. P, ofl~ lots have bed.cock at six (6) to eiffht (8) feet below
S--3780
Subdivision
All tile soil te~;t:~; .M~ow that th~s px'oposed development is not :mitable for
on-site wasto di, aposal, The soils ape eomple~el,y water sahamted f~om
the on~ (t) foot to ~he sixteen (1~) foot level. On.~file w~mte disposal
will not function in soils e, hmady we~t~r sahn'atod. ',Phis proposr~l
cannot meet our requirements for on-~4te wmate di~0posal.
is u lot line .qhift which does not lnerea~m dcnsiiy in this area.
showing troth lot~ ape suitable for c~a.-st/o w~ate disposal and
2-.lann ~ubdivision, Tracts A, I"~ and C
area is noted fop poor soils m~d a high w~tep tsble, Our field check
showed tibia aeea will probably have high w~tep to]Yb;~ probl~ma and
not be usuble until ~f~rved by p~olle sewer.
~$- 3747
and em~ bo adequately revi. ew~d,
5~3748
Amy's Subdivi:;-ion
All the data supplied (trails, water availability ,,'md slope) show that
these two Iota a~'e :milable fo,,,-, sinffle family da~w;:loprllont.
8-'3?49
Lot~; iOIA and tOlD
retunled or postponed 212il the data ts submitted and (mn be ~dequately
reviewed.
8--3750
Birehwood Park Subdivbfion
This propm*ty i,,.~ proposed fo~, community ?,,,}w,~r and water. The ppe. liminaz-y