Report g RECEIVED
B UILDING DIVISION
CITY OFTIGARD
LaVIELLE GEOTECHNICAL P.C. 2313 NE Alameda
Portland, Oregon 97212
(503) 287 -0511, Fax 282 -7671
September 17, 2012 our ref: 12- 2485.007
Pevzner Construction LLC
12846 Southwest Meader Way
Beaverton, Oregon 97008
RE: BEARING CONFIRMATION & DRAINAGE RECOMMENDATIONS
9425 SW 70 AVENUE
PORTLAND, OREGON r14 97020 g- p o A. o r
Sir:
In accordance with your request we visited the site during early September 2012. The
purpose of our site visit was to evaluate the foundation excavations and the proposed
foundation bearing material. In addition we provide a our drainage recommendations for the
property. Our observations and recommendations are presented below.
The soil exposed in the recent foundation excavations is a medium stiff, brown Clayey Silt.
This material is adequate and suitable to support conventional foundations designed for an
allowable bearing pressure of 1,500 psf. At the time of our site visit the proposed bearing
materials were ready to receive concrete.
The southern half of the site appears to be underlain by many springs and seepage areas.
Water was visible in the springs and in the seepage areas despite the long dry summer we
have recently experienced.
The proposed house will include a basement with a concrete floor slab. We recommend the
following measures be taken to maintained a dry basement.
The subgrade beneath the slab should be graded to drain to the low point drain.
Subgrade should be capped with a six -inch layer of round drain rock.
A moisture vapor barrier should be included between the drain rock and the concrete slab.
September 17, 2012 2 12- 2485.007
All of the below grade walls should be back filled with round drain rock and include a
footing drain.
Storm water should be discharged well away from the house and as far down the slope as
possible.
e are available to discuss the project.
Sincerely, 4Ct".
LaVIELLE GEOTECHNICAL PC /
-
Craig C. LaVielle, PE/GE y� Kx fE `'
Exp 12/31/12