HomeMy WebLinkAboutSPRING FOREST Block 2 Soils
DOWL Engineers
4040 "B" Street
Phone (907) 278-1551
January 5, 1983
W.O. #D12987
Grid: 2538
Anchorage, Alaska 99503
( Telecopier (907) 272-5742 )
Joe Cange
400 West 76th Avenue
Anchorage, Alaska 99502
Subject: Subsurface Investigation for Suitability
of On-Site Sewage Disposal, Block 2,
Spring Forest Subdivision
Dear Mr. Cange:
An investigation was performed at three locations on the
subject property to determine subsoil conditions and to
determine suitability for on-site sewage disposal. Trans-
mitted herein are the soil logs for the test borings, and
results of percolation tests conducted in adjacent test
pits. Also attached is a test boring location sketch. The
locations shown are approximate. They were located by pac-
ing and taping distances relative to road features. We
recommend that they be located by survey to avoid confusion
later.
Three test holes were drilled to depths of about 18 ~eet on
December 14, 1982, using a Nodwell mounted, Mobile B-61
drill fitted with a solid flight auger. The drill rig is
owned and operated by Denali Drilling, Inc. The drilling
was supervised and the test holes were logged by Mr. Carl
Bassler, geotechnical engineer with D~4L Engineers. Grab
samples were obtained at five foot intervals in each test
hole. As the samples were recovered, they were visually
identified, then sealed in plastic bags to preserve their
natural moisture content. After drilling, a perforated,
3/4-inch PVC pipe was placed in each test hole to monitor
water table elevations.
Backhoe pits were excavated on December 29, 1982, and Janu-
ary 4, 1983, for performing the percolation tests. The pits
were located about 10 to 20 feet south of the test borings,
and were excavated to depths of about 4 to 9 feet below the
ground surface. At the bottom of the pit, a hole was hand
dug with dimensions of about 1 foot by 1 foot, and 1 to 1.5
feet deep. The perco[Lation test was conducted in this
hole. Since soil conditions were not found to vary signifi-
cantly over short distances, and the terrain is relatively
flat, we expect that soil and groundwater conditions between
adjacent bo~ings and pits are similar for purposes of this
D~'~ Lewis E. Dickinson Maurice P. Oswald Kenneth B. Walch
Melvin R. Nichols
Joe Cange
January 5, 1983
Page Two
The percolation test was performed by filling each hand-dug
hole with water and allowing it to saturate. The following
day the hole was refilled with no more than 1 foot of water,
and the elevations of water in the holes were measured at 30
minute intervals for a four hour period. The percolation
rate given in this report was computed using the last 30
minute interval of the percolation test. The following
table lists the measured percolation rates.
Percolation
Test Pit Lot Zone
iA 9 4.5' - 5.5'
2A 12 9' - 10'
3A 14/15 5.5' - 6.5'
Measured
Percolation Rate
53 minutes/inch
40 minutes/inch
34 minutes/inch
If you have any questions regarding these tests, please feel
free to call.
Very truly yours,
Approved:
Melvin R. Nichols, P.E.
Partner
CAB:MRN:kf
Attachments
cc: Tim Potter-DOWL
DOWL ENGINEERS
Carl A. Bassler
Geotechnical Engineer
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