Report 03 /01/05 TUE 13:11 FAX 503 670 9147 t;Alci. uir t. 31 i i.0
• Carlson Geotechnical Alain Office Seiem Office Bend Office
P .O. Boot 23614 4060 Hudson Ave., NE P.O. Box 7918
A Division of Carlson Testing, Inc. Tigard. Oregon 97261 Seism, OR 97301 Bend, OR 97708
Geotechnical Consulting Phone (503) 884 -3460 Phone (503) 599-1252 Phone (541) 330 -9155
Construction Inspection aetd Related Tests FAX (503) 670.9147 FAX (503) 589 -1309 FAX (541) 330-8163
Final Summary Letter
June 14, 2004 C ! 2co 3 -cro 33 )
Mr. Mark Hansen /v 0� 5 l/ ri� r wc�d PI
Derek L. Brown & Associates, inc. �/
9500 SW Barbur Blvd., Suite 220
Portland, Oregon 97219
Re; Final Letter of Geotechnical Observations
Hawks Beard Totrinhomes
SW Hawks Beard Street
Tigard, Oregon
CGT Project G0202050.A
Carlson Geotechnical (CGT) served as geotechnical Engineer -of- Record (EOR) for the Hawks
Beard Tow nhomes project, located at the intersection of SW 130 Avenue and SW Hawks Beard
Street in Tigard, Oregon. We performed a geotechnical investigation of the site, the results of
which were presented in our report of Geotechnical Engineering Services dated December 10,
2002, and performed geotechnical observation during construction. Our observations were
completed on an c;n -call, part -time basis betw the dates of November 19, 2002 and July 17,
2003. This letter concerns observations and testing performed on Lots 1-6 since the final
summary fatter dated Novembsr 1 2003 was s of out.
o S Stripping: Prior to consttruction, the site contained su,eace vegetation in
structural areas. Roadways and lots were et,iuped of vecetation between
November 19` ar.d 25 2002 Based on our field observations, the site ',WJaS
stripped of organic topsoil in general accordance with our recommendations.
• Subgrade Cond Lions; After stripping had been completed, the site subgrade soil
was cement treated for planned construction activities in the winter. Based on our
field observations, the subgrade soil has been prepared in general accordance
with our recommendations.
o Roadway Finn Placement and Compaction: Up to 2 feet of fill was placed and
compacted on roadways in the southeast corner of the site. CGT conducted 6 in-
place relative compaction tests on the native brown silt fill. Based on our field
observations and in place density testing the native silt fill for roadways was placed
and compacted in general accordance with our recommendations (92 percent of
ASTM D- 1557).
• Roadway Aggregate Base Rock: CGT conducted 12 in -piece relative compaction
tests on the roadway aggregate base rock on May 2, 2003. The roadway
Ui3 /Ul /US TM 14:11 rA& SUJ o u b191
t'r12lLJV1N inalinJ ���� _
• Hawks Beard Townhomes
Tigard, Oregon
June 14, 2004
aggregate base rock was prepared in general accordance with the
recommendations given by the City of Tigard (95 percent of AASHTO T -99).
'''oad,ay Pavements: Asphalt was placed on the South Alley, North Alley,
Hazelwood, Briarurood, Woodridge. Huntington, and Hawks Beard on May 13,
2003- CGT conducted 17 in -place relative compaction tests on the asphalt. Test
resu is rar:gecl from 91 to 93.1; percent of ASTM D -2950.
O L t : Based on our t:e.!d obsenfe ions, lots 8 thrc;,tgh 1a, rf' lots 1 through 3
C!1" ti C arc on ::at've si -ii The rernair;;i'ig 53 lots are on stnrucii':al 'ii.] up to 3 feet
de p. Based on our observations and in -place relative compac ion testing, to 1
through 62 have bean prepared in energy' a. a 3 .. ^ e
. - ::; :7 ..._._::]:�cd S:Ss:a^."w5": rcund'ation bearing surfaces'.rere not prepared
at the tirna of this report; therefore, we have not cbsenierl any of the fc'lnda ?i ^n
sibgrece sc:t= ' ti prcr•'tSnd• i'esidenC c `� - -
su.
�j �•.Y.V �..- �-\'.J.: •.:. :.. •- 11.:2': I,.G C:I II�J��!
a J . - .:i:.::rs- . ,YC —Ziv -:(LUG L-- ant l::l..:Act- hLV`c; -:U 31.I lG•.v•_ a.;1c VG'.liu,,; ai14-p rJr -to
pErcTi :',i:i't rti;i'a. We underseenci than the G'.y of Tigard wit/ nr73 rer3_f a
. fi-' '.•'L'_ . ' ici fat.4 :?M:'l::.7 s: _` ;: eda C'✓
+•.'u., • . VrYi a ,::c`.c=; 9i cc 'ur'aLidic. CG1 conducCeC: 28 in-p it:e relative
ccmoe -• tests t t 1 .Lt' t , e�
Lt i l:.• ,. S Gr: IaN! i r�ric= "t ,•�r... ; - t -;i_l: 7- th= co- " . w,i.:-2,. ,
_., ,JCr -•'c^,.••.-., D .:cd on our d.=•ns:ty i%s ing, :i•. Jiii.ii i,e ic;les. j::.icAriil has been
,_Yfrnpa n ge _
i .._'C in =ra> accordance with the recommendations given by i =.Ili: of
Tigard (95 percent of AASHTO T -99).
Based on our observations, as fsuoui li'oi.e.d in our field repo; ts, and iG the best or our knowledge,
within our scope of work, the above geotechriicai summaries accurately reflect our observations.
Our service; were provided on an on -call basis, in which we rel;ed on the. contractor to contact - v CC u.... vvr
offico to:• the schedi ii g of our services. Wi:t cant tot b@ held conireciluejiy responsible for th
items, of any. that we did not obser• or test.
Sincereiy
k ed 'v,GL .tit lit =: t.
u •technical Staff -.
,..-...., ._ /0,.... _ - nne M. reme', P.E. ; ' :`s t.z..st_ _
, i. G. *technical Engineer
Dec IQ: P ;tGEOTEi'.HlPROJECTS12002 ProiectsV4a Beard Tore:humes - COSIFn i l9tt`r.DOC
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