HomeMy WebLinkAboutWILDWOOD GLEN Geological & Soils Investigation
aP'plied earth sciences
August 12, 1971
Hewitt V. 'Lounsbury and Associates.
723 West Sixth Avenue
Anchorage, Alaska 99501
ATTENTION: Mr. Bud Herschbach
Re: Geologic and Soils Inveatigation - Wildwood Glen Subdivision
Gentlemen:
Transmitted herewith in accordance with your request is our report
of the geologic and soils investigation of the above-captioned property.
We have enjoyed being of service to you on this project.
ff we can be of further service.
Very truly yours,
Please. call
HJM:js
Attachment
ALASKA GEOLOGICAL CONSULTANTS
Telephone: 277-7601 277-7602
- 2227 SPENARD ROAD · ANCHORAGE, ALASKA 99503
GEOLOGIC AND SOILS INVESTIGATION
OF
WILDWOOD GLEN SUBDIVISION
REPORT TO
HEWITT V. LOUNSBURY & ASSOCIATES
ENGINEERS - SURVEYORS
mEPARED BY
ALAS~ GEOLOGICAL CONSULTANTS
ANCHORAGE, ALASKA
AUGUST i~?1
INTRODUCTION
This report sets forth the results ofa geologic and soils investigation conducted
o~ Wildwood Glen Subdivision, a proposed residential subdivision. Located outside the
area serviced by water and sewer utilities, the development is planned for on-site water
sdpply and sewage disposal facilities. The purpose of this investigation was, therefore,
to.I determine the geologic and'soil conditions at the site to facilitate proper design of the
s~wage disposal system..~ }'
INVESTIGATION
Geologic and soils data at this site were obtained through a geologic recon-
naissance of the property followed by a drilling program designed to provide data on
subsurface soils and drainage conditions. Three test borings were drilled utilizing a
. Gb-Track mounted B-40 Mobile drill, The borings were advanced using solid flight
auger equipped with a D-P rock bii.
a ?taft engineering geologist.
ENGINEERING GEOLOGY
Sampling, logging and inspection Were provided by
Wildwood Glen comprises approximately ten acres of the lower slopes of the
Chugach Mountains east' of Anchorage. The lot sizes are large, ranging from approximately.
One acre up. The site has been mapped as a lateral moraine by the U. S. Geological
Survey. The moraine was deposited along the margin of glacial ice during the Pre-
Wisconsin "Knik" glaciation. The topography is typical of lateral moraines with linear
ridges parallel to the direction of ice m. ovement~ Side glacial streams were responsible
for a considerable amount of sorting in the morainal material resulting .in d eposits of
sand and gravel
_ Surface drainage tl!r..o,,u, ghout
co~untered in the .teq~, Borings which, were
drainage, can be expected to be ~apid'owin
.e area is g0od.] 'the water table was not en-
tilled.to depths up to 24.5 feet. Subsurface
to the abundance of gravels and sands beneath
the silt topsoil mantl% . ........ ' "·
SUBSURFACE MA'~ER IA LS '~'lq'/) 'C0 ND ITIO NS
Subsdrface' dataTp'6rtainin~ io this site are shown on the enclosed boring logs.
Location of. the borings ar?.shown on the plan'of b6rings. The soils ~onsist of water-
sorted glacial sands, gravels and silty sandy gravels of lateral moraine, origin, _The
materials present near the western b.oundary of the subdivision generally contain more
silt with a corxesponding decrease in percolation rate.
CONCLUSIONS AND ~RECOMMENDATIONS .- -
On the basis 6f information gathered in this investigation, we draw the following
principal conclusions: ~i . i 'fi'
/
· i i. Lot ,sizes are adequate fo~ ori-site sewage dispos.al u iliz ng the ~/ .
conventional septic 'lank-seepage p~t ,system.,.
2.Seepage area requirements for individual systems will r/~nge' from
125' to 325 squdre feet!pe~'bedroom.
In view of the variable nature iof the subsffrface soils on .the Site, -we recommend
that a soils, investigation on each lot should be required prior to installation ot the sewage
in order to define the. seepage areh require, ments for the particular lot.
_~-~2~e~'~%~ ' Respectfull;g submitted,
.,..~ ' 0,?.. ~ '~ '~ ' "
~_~... ....... .~a ~ ,. ~ ~s~ ~nomc~ca~ co~su~x~s
, ~ . ~ .75 E
~.~/~o.*, g-~ ". Nmi H. ~elker
disposal system
LOG OF' BORING NO.
WILDWOOD GLLt S[JBDIVISION
TYPE BORING: Au~'cr IJ.3CATION: See
m ~ SOIL DESCRIPTION
Ld ~ ~
~ SUR. EL~V.: 805'
~ Organic tops?il'
Sandy gravel with silts (GP) ~ 125 square feet per
bedroom
-- Medium sand with occasional g~avels (SP) - 150 square
;~': feet per bedroom
-10' ....
~:.~
20.
-~r~';'
,. .... Gravelly sand to s~dy gravel (SW-GW) - 100 square
:~.~ feet per bedroom
-254
~MPLETION ~TH: 23.5' D~YH TO W~TE~:.Nowater
DATE: ,lune 10, I971 DATE:
SK :01KA GE LOGICAL CONSULTANTS
LOG OF BORING NO. ?
· WILDWOOD GLEN SUBDIVISION
TYPE BORING: Aug'er LOCATION: See Hah
m SOIL DESCRIPTION
SUR, ELEV,: 815' ~-,
.... Topsoil previously str~pped. Sandy g~avel to gravelly
:..> sand (GW-SW) - 100 square feet per bedroom
:'O.
'~.;~ Poorly graded medium sand (SP) - 150 square feet per
· · bedroom
-10 ":
.... · Stratified sand and grave~ (GW) - 85 square feet per
,~ %: i
-15 -' · bedroom
-20 .,iC. ,
-25
.[
~MPLETION ~EPTH: 24.5' DEPTH TO WATER: No water
DATE: June 11, 1971 DATE:
~ LOG OF BORING NO.
: WILDWOOD GLEN SUBDIVISION
TYPE 8ORING: Aug'er LOCATION: See Plan
o /' SUR. ELEV.:
· '~ Sandy g~avel w~ some silt (GM)'- 225 square feet
· : ..per bedroom .
-20 -
~MPL[TION ~PTH: 19.5' D~TH TO WATER: No.water
DATE: .June 11, 1971 DATE':
pAN~AMA
LEGEND
i~THIS ~
2O
,~y
WILDWOOD GLEN SUBD.
LOCATED IN
NE I/4 ,S%I~ II4, NW I/4 , SEC 15 ,TI2 N, R3W,
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