HomeMy WebLinkAboutCT 04-18; OCEAN MIST CONDOMINIUMS; SOIL CORROSIVITY RESULTS, PROPOSED OCEAN MIST CONDOMINIUMS; 2004-07-09Geotechnical • Geologic • Environmental'
5741 Palmer Way • Carlsbad, California 92008 • (760) 438-3155 • FAX-(760) 931-0915.
July 9, 2004
W.O. 4369-A-SC
RDA Designs. 0
P.O. Box 40
Carlsbad; California 92008'
Attention: Mr. Ron Alvarez
Subject: Soil Corrosivity Results, 'Proposed Ocean Mist Condominiums, 325-347 Oak
Avenue, City of Carlsbad, San Diego County, California
References: . 1. Geotechnical Evaluation, Proposed Ocean Mist Condominiums, 325-347 Oak
Avenue, City of Carlsbad, San Diego County, California," W.0.4369-A-SC, dated
June 21, 2004, by GeoSoils, Inc.
2. "Uniform Building Code" Whittier, California, Vol. 1, 2, and'3, dated 1997, by International
Conference of Building Officials.
Dear Mr.: Alvarez:
As discussed in Reference No. 1, GeoSoils, Inc. (GSl) conducted sampling of
representative soils on the subject site for corrosivity. Laboratory test results were
completed by M.J. Schiff (consulting corrosion engineers). Unless specifically superceded
herein, the conclusions and recommendations contained in the referenced report by GSI
remain pertinent and applicable, and should be appropriately implemented during design
and construction. 0
SUMMARY
Atypical sample of the site materials was analyzed for corrosion/acidity potential (attached
as Figure 1, following the text of this letter).. The testing included determination of soluble
sulfates, pH, and saturated resistivity. Results are as follows: site soils are generally mildly
alkaline (pH of 7.7), are moderately corrosive to ferrous metals (i.e., 7,200 ohms-cm), and
have a negligible potential for sulfate exposure to concrete (i.e., 0.0070soluble sulfate
percent by weight in soil). Alternative methods and additional comments regarding
foundations, piping, etc., should be obtained from a qualified corrosion engineer.
3Q
We appreciate the opportunity to be of further service. If you should have ányquéstidns,.
please do not hesitate to c e. .
Respectfully submitt
ut
GeoSoils, Inc 0 No 1117 ( fl.E4737
Engineering Geologis, EG 1117 Civil Engineer, RCE 47857
DG/PLM/DWS/Jh
Attachment: Figure 1..- Corrosion Test Results S
Distribution: (4) Addressee . .
RDA Designs : ..
.. W.O. 4369-A-SC
325-347 Oak Ave., Carlsbad S July 9, 2004
FiIe:e:\wp9\4300\4369a.scr S S Page 2
GëoSoils, Inc
M. J. Schiff & Associates, me.
Consulting corrosion Engineers - Since 1959 Phone: 909) 626-0967 Fax: 909) 626.3316
431 IV. Baseline Road S E-mail lab@rnjsch?ff corn
: Claremont, CA 91711
.
. . website:. njschjff corn
• Table 1 - Laboratory .Testi on Soil Samples
Salmen
.
. . Your #4397-A-SC, MJS&A #04-0838LAB
. 18-Jun-04 .
.
.
Sample ID . . . . . .. .
B-i. . . .
@0-4' . ...
Resistivity Units
as-received . ohm-cm 62,000 .
saturated ' ohm-cm 7,900 . .
pH .7.3
.
. Electrical . .
.
. . . . . . .
.
Conductivity. ms/cm . . 0.09 .
Chemical Analyses
Cations . . .
calcium Ca' mg/kg . . 40
.
magnesium. Mg2+ mg/kg 12
sodium Na mg/kg 86 . .
Anions . . .
carbonate C032 mg/kg ND
bicarbonate HCO3 mg/kg . 211
chloride C11-mg/kg 15
sulfate S042,mg/kg 138
Other Tests .5 .
.
.
S.
animonium NH mg/kg • na • • . . . • •
nitrate NO3 mg/kg na . • . •
•
sulfide S2 qual na • S •
Redox mV na .
• 5.. • • •• • • .••• • •
Electrical conductivity in millisiemens/cm and chemical analysis were made on a 1:5 soil-to-water extract.
mg/kg = milligrams per kilogram (parts per million) of dry soil. • • •
• Redox = oxidation-reduction potential in millivolts
ND = not detected • •
na = not analyzed .• S
FigUre 1
Page lofl