Report Alder Geotechnical Services 3910 NE 10`" Avenue
Portland, Oregon 97212 -1221
Phone 503.282.7482
Fax 503.282.7402
August 23, 2002
Project No. 364 -2 COPY
Mr. Hap Watkins, Supervising Inspector
City of Tigard Building Division
13125 SW Hall Boulevard
Tigard, Oregon 97223
FINAL REPORT OF SPECIAL INSPECTIONS
NEW PIN PILE RETAINING WALL BEHIND UNITS 62 -67
QUAIL HOLLOW WEST, 13021 SW RAPTOR PLACE
TIGARD, OREGON
Permit No. BUP2002 -00309
Dear Mr. Watkins:
I have completed by observation of the subject retaining wall construction. The purpose of my
site visits was to determine whether the wall construction was performed in general accordance
with my approved plans dated June 19, 2002. This letter presents my opinion that the work was
performed in substantial accordance with my design.
The new steel pipe pile retaining wall was constructed behind Units 62 to 67. The wall was
constructed using 21' long, 4 "- diameter Schedule 80 steel pipes driven into the ground at
approximately 2' spacing. The height of the wall ranges from about 2' to 5'. The maximum
height allowed by the design was 6'.
The backs of the pipes were lined with Maccafferi zinc - coated, double twist 8x10 mesh and
backed with zinc - coated 16 -gage mesh. The mesh was backfilled with 4" -minus crushed rock
and covered with soil for landscape purposes.
In my opinion, the wall was constructed in substantial accordance with my design. Please call me
if you have questions.
Sincerely,
ALDER GEOTECHNICAL SER;" ,4,
/01Am 1 • �-�
13507 `- A
John N. Cunningham, P.E.
Geotechnical Engineer 4,
CUNO ex P.
lZ - 3 1 . -0 3
(1) Addressee -
(1) Mr. Manuel Castaneda Pro Landscape, Inc.
(1) Mr. Ron Esty, Brownstone Homes, Inc.